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HomeMy WebLinkAbout1996-12-16 City Council (44)CiU of Palo Alto City Manager’s Report TO:HONORABLE CITY COUNCIL FROM:CITY MANAGER DEPARTMENT: Planning and Community Environment DATE:December 16, 1996 CMR:510:96 SUBJECT:City Review and Response to the Santa Clara Valley Water District Draft Environmental Impact Report for Adobe Creek Watershed Project REQUEST Council is requested to review and comment on the Draft Environmental Impact Report (EIR) for the Adobe Creek Watershed Project and direct staff regarding the City’s response to the Draft EIR. The project includes two channel modification sites (900 linear feet at West Edith Avenue, and 1.500 linear feet at Foothill College); six culvert replacements; 17 erosion repair sites; and ongoing maintenance progam projects. One proposed culvert replacement at E1 Camino Real and six of the proposed erosion control sites are located within Palo Alto, affecting approximately 500 linear feet of the Creek within the City. RECOMMENDATIONS Staff recommends that the City Council direct staff to respond to the Santa Clara Valley Water District Draft EIR for the Adobe Creek Watershed Project, with the City’s response to include: 1 ) the comments recommended in the attached Planning Commission staff report; 2) Exhibit A prepared by the City’s consultant; and 3) the comment added by the Planning Commission that sack concrete should not be used in natural portions of the Creek. POLICY IMPLICATIONS The Draft EIR identifies deterioration of the quality of the wildlife habitat of the Creek as a result of the proposed project. Proposed mitigation is the planting of mixed riparian forest on several identified mitigation sites along Adobe Creek. These proposed off-site mitigations, rather than in-kind on-site replacement, do not appear to be consistent with the CMR:510:96 Page 1 of 4 City’s goals and policies for protection and conservation of ecological and scenic qualities of wildlife areas. See pages 2 and 3 of the attached Planning Commission staff report for a discussion of these policy issues. A project approach that seeks to avoid damage to wildlife habitat, with in-kind on-site replacement as the next preferred option, would be more consistent with the conservation objectives, goals and policies of the Palo Alto Comprehensive Plan. EXECUTIVE SUMMARY The Santa Clara Valley Water District forwarded the Draft EIR for the proposed Adobe. Creek Watershed Project to the CiB~ for review and comment. City staffwas assisted in their review of the document by a consulting hydrologist and geomorphologist. The consultant’s qualifications are attached to this report. A summary of the consultant’s recommendations are on pages 3 and 4 of the attached Planning Commission staffreport, and the complete text of the consultant’s recommendations and supporting general comments are found in Exhibit A. Additional recommendations by City staff, including questions regarding the adequacy of the proposed off-site mitigation measures, are on pages 5, 6 and 7 of the attached Planning Commission staff report. On November 20, i996, the Planning Commission unanimously recommended that comments responding to the Draft EIR be forwarded from the CiB, to the Santa Clara Valley Water District, including comments prepared by staff in the Planning Commission staff report, the comments prepared by the consultant in Exhibit A, and an additional comment recommended by the Planning Commission that for ecological and aesthetic reasons sack concrete should not be used in natural areas of the creek. Commissioner Byrd also requested that staff arrange for the consultant to repeat the presentation made at the Planning Commission meeting for Mr. Greg Zlotnick, the newly elected member of the Santa Clara Valley Water District Board, representing thePalo Alto area. After the Planning Commission meeting, staff discovered that the statement on page 5 under item 5.a., "’none of the mitigation sites are located within Palo Alto," is incorrect. One of the mitigation sites is within the City, located at the southeast City boundary between Adobe Creek and Foothill Expressway. This site is described on page 87 of the EIR as a .4 acre meadow, including numerous small oaks and some large California bay trees. The location of the site within Palo Alto does not affect staff’s concern about the inadequacy of the proposed off-site mitigations. ALTERNATIVES The actions available to Council include adopting the Planning Commission recommendation to forward the comments of the staff, consultant and Planning Commission to the Santa Clara Valley Water District in response to the Draft EIR, to modify those comments, or direct staff to make no response to the Draft EIR. CMR:510:96 Page 2 of 4 FISCAL IMPACT This response to the Draft EIR has no fiscal impact to the City. STEPS FOLLOWING APPROVAL Written responses to the Draft EIR may be submitted during the review period, which ends January 3,1997. If so directed by the Council, staff will submit written comments on the Draft EIR to the Santa Clara Valley Water District prior to the end of the review period. ATTACHMENTS Planning Commission Staff Report, November 20,1996 Exhibit A: Consultant’s Comments Februa~ 27, 1995 letter to Santa Clara Valley Water District September 6, 1996 letter from Department of Fish and Game in response to Portola Valley Training Center project regarding use of gabions in San Francisquito Creek November 18, 1996 letter from Linda Elkind November 20, 1996 letter from Santa Clara County Creeks Coalition Qualifications of hydrology and geomorphology consultant, Mitchell Swanson Minutes of the November 20, 1996 Planning Commission meeting Draft EIR for Adobe Creek Watershed Project (Council Members only) CC:Terrence A. Neudorf, Santa Clara Valley Water District, 5750 Almaden Expressway, San Jose, CA 95118-3686 Scott Wilson, Santa Clara Valley Water District, 5750 Almaden Expressway, San Jose, CA 95118-3686 Craig Breon, Santa Clara Valley Audubon Society, 22221 McClellan Road, Cupertino, CA 95014 Dena Mossar, 1024 Emerson Street, Palo Alto, CA 94301 Debbie M~els, 2824 Louis Road, Palo Alto, CA 94303 Libbv Lucas, 174 Yerba Center Avenue, Los Altos, CA 94022 Linda Elkind, Town of Portola Valley, 765 Portola Valley Road, Portola Valley, CA 94028 Margaret Roper, Biologist, Region 3, Department offish and Game, 7329 Silverado Trail, Napa, CA 94558 City of Los Altos, Attn: Larry Tong, Planning Director, 1 North San Antonio Road, Los Altos, CA 94022 City of Los Altos, Attn: David Kornfield, Associate Planner, 1 North San Antonio Road, Los Altos, CA 94022 City of Los Altos Hills, Atm: Curtis Williams, 26379 Fremont Road, Los Altos Hills, CA 94022 CMR:510:96 Page 3 of 4 Foothills College, Attn: Bemardine Chuck Fong, President, 12345 E1 Monte Road, Los Altos Hills, CA 94022-4599 Mike Rigney, San Francisco Estuary Institute, 1325 South 46th Street, Richmond, CA 94804 PREPARED BY: Virginia Warheit, Senior Planner DEPARTMENT HEAD REVIEW: CITY MANAGER APPROVAL: KENNETH R. SCHREIBER Director of Planning and Community Environment Ci ~N.R4anager CMR:510:96 Page 4 of 4 TO: FROM: PLANNING COMMISSION STAFF REPORT Planning Commission Virginia Warheit DEPARTMENT: Planning AGENDA DATE: November 13, 1996 SUBJECT:City Review and Response to the Santa Clara Valley Water District Draft Enviromnental Impact Report for Adobe Creek Watershed Project REQUEST/PRO~CT DESCRIPTION Staff requests that the Planning Commission review the Draft Environmental Impact Report (EIR) for the Adobe Creek Watershed Project and the recommended comments on the Draft EIRprepared by city staff and the city’s consultant, and make recommendations to the City Council regarding the city’s response to the Draft EIR. The project includes two channel modification sites (900 linear feet at West Edith Avenue, and 1500 linear feet at Foothill College); six culvert replacements; 17 erosion repair sites; and ongoing maintenance program projects. One proposed culvert replacement at El Camino Real and six of the proposed erosion control sites are located within Palo Alto, with these projects affecting approximately 500 linear feet of creek. RECOMMENDATION_ S Staff recommends that the Planning Commission recommend that City Council direct staff to respond to the Santa Clara Valley Water District Draft Environmental Impact Report for the Adobe Creek Watershed Project, with the city’s response to include the comments recommended in this report and in Attachment A prepared by the city’s consultant, and any other comments that the Planning Commission may recommend. A!PCSRISCVWDEir.sr Page 1 11-08-96 POLICY IMPLICATIONS Several policy related issues are raised by the proposed projects and the EIR, including flood control, water quality, conservation and protection of environmental and aesthetic qualities of natural areas, and urban design. While the proposed projects appear to be consistent with Palo Alto Comprehensive Plan policies with regard to flood control and water quality, the EIR identifies impacts and proposed mitigations that may not be consistent with resource conservation and urban design policies and programs of the Comprehensive Plan, as outlined below. In addition to Comprehensive Plan policies, some of the projects proposed in Palo Alto may not be in compliance with the city’s Tree Ordinance that protects Live oak and Valley oak trees over 11.5 inches in diameter. Comprehensive Plan Natural Resources and .Open Space Elements." The Natural Resources Element identifies the watersheds of all creeks in the city, including Adobe Creek, as natural resources to be protected, and further states as a conservation objective, "Prevention of damage to structures must be achieved with the least possible alteration of the natural ecology." Additional goals and policies related to conservation are located in the Open Space Element. This Element identifies the need "to preserve the ecological balance of the indigenous biotic communities and to maintain plant associations and wildlife habitat." Relevant Open Space Element goals and policies are: Goal #6: Protection and-conservation of open spaces which are vital as wildlife habitat, and of areas of major or unique ecological significance. Policy #4: Protect conservation and scenic areas from deterioration or destruction by either private or public actions. " The EIR recognizes that the proposed projects will result in a deterioration of the quality of the wildlife habitat of the Creek, including the proposed Palo Alto project site upstream of the E1 Camino Real culvert. Proposed mitigation is planting of mixed riparian forest on several identified mitigation sites along Adobe Creek. All of these mitigation sites are located outside the city of Palo Alto. In addition, the city has some concern about the adequacy of the proposed off-site mitigations as addressed on page 5. For these reasons, the project does not appear to be consistent with the city’s goals and policies for protection and conservation of ecological and scenic qualities of wildlife areas. A project approach that seeks to avoid damage to wildlife habitat, with in-kind on-site replacement as the next preferred option, would be more consistent with the conservation objectives, goals and policies of the Palo Alto Comprehensive Plan. A [ PCSR f SCVWDEir.sr Page 2 11418 -96 ,Comprehensive Pla~ Urban Design Element: The Urban Design Element identifies the E1 Camino Real crossing of Adobe Creek as an important city gateway. Policy 7: Strengthen gateway identity. Program 23: Plant groves of tall trees and emphasize bridge structure and entrance sign at Palo Alto’s south gateway on E1 Camino Real. The graphic illustrating this program in the Comprehensive Plan calls for retaining the existing grove of trees on the downstream side of the bridge and adding dense tree planting upstream of the bridge to call attention to the riparian setting and heighten the gateway feeling. As described on pages 7-5 and 7-6 of the Engineers Report, it is anticipated that the E1 Camino Real culvert will be a cooperative project with the City of Palo Alto to implement the gateway concept. The city has been working informally with the District on this project for the past two years and is very appreciative of District’s willingness to collaborate on the project to accomplish the objectives of both jurisdictions. However, we are concerned that the specific project design being proposed will make it difficult to achieve the objective of an attractive riparian gateway in this location, since the project appears to remove existing riparian trees and shrubs both downstream of the bridge and for about 200 feet upstream of the bridge, and the gabion baskets proposed to line the creek banks in this location will not support plant materials necessary to reestablish a natural riparian appearance. EXECUTIVE SUMMARY City staff has been assisted in their review of the Draft EIR by a consulting hydrologist and geomorphologist. The consultant’s comments and recommendations are in Exhibit A attached to this report. In summary, the consultant concluded that: 1) The City’s natural resource conservation policies dictate an impact avoidance approach over impact minimization. Where treatments are needed and avoidance is not practical, the next strategy should be to mitigate habitat impacts "on-site" and "in-kind. 2) Overall, the proposed treatments for Adobe Creek are too generalized for site conditions. Opportunities to avoid impacts can be realized by conducting site-specific analyses, rather than a broad Reach-by-Reach approach, and by incorporating principles and concepts of fluvial geomorphology (the scientific study of stream channels and the processes that form A ! PCSR I SCVWDEir.sr Page 3 11-08-96 them). 3) Where treatments are likely needed, there are suitable alternatives that reduce impacts and provide opportunities to restore habitat resources on site, rather than the proposed off site mitigations. The consultant’s recommended response to the Draft EIR includes the following general comments. Additional comments and discussion are included in Exhibit A attached to this report. Implement a mitigation program that incorporates an impact avoidance approach to planning specific design solutions for individual sites. This would be accomplished by conducting field and research analyses during the construction plan development. The program’s objectives would include a Consensus assessment of the risks associated with various alternatives, and the selection of treatments that best merge the District’s objectives with the City’s conservation policy goals. By incorporating this mitigation measure, the City will gain greater confidence that a site-specific impact avoidance analysis occurs in planning the project. This mitigation program will also help overcome an inherent difficulty of understanding important, site- specific details and aspects of the proposed treatments through an environmental document alone. A prime example is the use of habitat acreage in the document rather than a discussion of impacts on specific sites, on the continuity of habitat or on individual significant trees which are important according to the City’s policies. Conduct further research into alternative bank protection techniques that provide greater opportunities to avoid impacts or to mitigate them on site. The emphasis should be on those treatments that best minimize impacts and allow preservation of existing significant vegetation and/or proper conditions for vegetation growth. This would include the use of fabric encapsulated soils, channel bank toe protection instead of full bank slope treatments, and other methods of sustaining riparian vegetation. Incorporate a geomorphic analysis of the proposed sites to: a) determine whether the channel is stable based upon regional stable channel relations; b) assess the channel forming processes and their relation to channel stability; c) identify treatments for site specific problems. Conduct a detailed review of the proposed channel maintenance program to reflect the City’s resource conservation policies. The following are additional comments on the Draft EIR prepared by city staff. A I PCSR / SCVWDEir.sr 1 l~-eg~ Adequacy of the proposed mitigation for loss of habitat. The Draft EIR recognizes that "the loss or degradation of any mixed riparian forest within the riparian corridor, due to vegetation removal or the placement of gabions or riprap from the project, is a significant impact" (page 77). The proposed project results in impacts on the riparian habitat along several thousand linear feet of the creek, with about 500 linear feet of the impacted area located in Palo Alto (projects in Reaches 1 and 2). The proposed mitigation for the impacts on riparian habitat resulting from all the proposed projects, including the projects in Palo Alto, is the establishment of mixed riparian forest on several identified mitigation sites contiguous with Adobe Creek, with a replacement ratio of 1:1 to 3:1, according to the existing habitat value of the impacted areas. The following questions are raised about the adequacy of this proposed mitigation approach: a)None of the mitigation sites are located within Palo Alto, raising questions about compliance with the Comprehensive Plan policies regarding conservation and protection of wildlife habitat in the city. (See discussion of policy implications on pages 1 and 2.) For mitigation of impacts on sites within Palo Alto, avoidance of impacts, followed by in-kind on-site replacement where impacts are necessary, would be more consistent with the Palo Alto Comprehensive Plan. b)All of the proposed mitigation sites are described as currently having some riparian habitat value, that is, they are not entirely new habitat areas. The amount of mitigation acreage being provided appears to give full credit for the replacement.habitat areas, rather than a prorated credit based on the incremental increase in habitat value of these mitigation sites. c)Final success criteria for revegetation of the mitigation sites are not identified in the EIR. d)According to the EIR (page 105), the mitigation sites will not provide full riparian habitat value for at least 15-25 years after planting. The amount of mitigation acreage that is being provided does not appear to have been adjusted for this delayed replacement. e)The three types of habitat that are being lost, as described on pages 51-53, are: 1) mixed riparian forest (trees at or beyond top of bank); 2) riverine A !PCSR t SCVWDEir.sr Page~ 11-08-9~ (channel bed and banks located within the ordinary high water level); and 3) scrub (special dry land vegetation habitat). These three types of habitat function as parts of an interrelated ecosystem. The EIR does not address the possible impacts on the habitat value of the creek corridor of losing primarily riverine habitat, but providing only mixed riparian forest habitat in the mitigation areas (page 105). Nor does it address the possible reduced value of providing the mixed riparian forest at mitigation sites where the adjacent riverine habitat is of low quality, with minimal mutually supportive benefits, such as at Foothill College where mitigation planting is being proposed along a section of the creek bank where the creek channel will be covered with rock riprap and the creek banks lined with gabions. This method of assessing impact on wildlife habitat by summing acres of affected habitat does not take into account the corridor characteristics of a riparian habitat, since it ignores the importance of continuity of the habitat corridor, and gives more weight to area than to the linear feet of creek that is affected. o Aesthetic impacts of proposed project. The EIR concludes that the project results in no significant aesthetic impact and so no mitigation is required (pages 118-122). However, it appears that there would be a significant change to the visual character of the creek as a result of the channel modification projects at Foothill College and at West Edith Avenue, and also as a result of the bank modifications that are part of the proposed culvert project at E1 Camino Real. At the Foothill College site, approximately 1500 linear feet of the creek channel is being widened and both banks are being lined with gabions 6 feet up the bank, The EIR identifies the current habitat of this site as predominantly of high value (page 78). The EIR further states (page 81) that the proposed gabions are a "hard" material that "would...inhibit the establishment of native vegetation (both landscaping or natural recolonization)". (See photo simulations on page 122.) While replacement planting is. being proposed beyond the top of creek bank, the widened creek channel and gabion-lined banks will not support the reestablishment of natural riparian vegetation, and the sharp, straight lines of the gabion embankments will become the predominant character of this part of the creek, rather than a natural riparian character. Since this site is located in a highly visible location at the entrance to a major community facility, such a change to the visual A ] PCSRI SCVWDEir.sr Pagea6 I 1-08-~ character of the creek would appear to constitute a significant alteration of an important scenic resource. At the E1 Camino Real site, the first 100 feet upstream is mostly lined with concrete but includes several trees and beyond that the banks are heavily covered with native riparian trees and shrubs. The proposed project appears to remove all vegetation on both banks for more than 200 feet upstream. There is currently a grove of redwood trees and other vegetation immediately downstream of the bridge, and it appears that they also would be removed by the project. This would have a similar effect as at the Foothill College site, to change the appearance of the creek from a primarily natural condition to one dominated by engineered structures. Since this project site is located at a major entrance to the city that is identified in the Comprehensive Plan for special treatment, this change to the appearance of the creek would substantially alter a significant scenic resource. 7.Palo Alto Tree Ordinance. The Regulated Habitats section of the EIR (page 67) discusses the tree ordinances of Los Altos and Los Altos Hills, but not Palo Alto. In July, 1996, the Palo Alto City Council adopted a Tree Ordinance that protects Live oak and Valley oak trees that are 11.5 inches or more in diameter at 4.5 feet above natural grade. Construction Impacts. Construction-related impacts from the proposed replacement of the culvert under E1 Camino Real are identified as temporary impacts to traffic movement and on-street parking, and implementation of a detour plan is proposed as mitigation. Additional impacts that need to be considered and mitigated include disruption of pedestrian and bicycle circulation and the impacts on business located near the project area. Information about Special Flood Hazard Area (SFHA). As a result of the District’s study of Adobe Creek, will the new SFHA be larger or smaller than the currently mapped areas? Will the mapping be more accurate than the existing (i.e. will base flood elevations be provided for the area at the end of Miranda Green?). Many of these issues were raised by the city in response to the Notice of Preparation of the EIR in a February 27, 1995., letter to the District. A copy of that letter is attached to this report. A [ PCSR I SCVWDEirsr 11 ~8g-eg~ FISCAL ..IMPACT This response to the Draft EIR has no fiscal impact to the city. ATTACHMENTS/EXHIB!TS: Exhibit A: Consultant’s Comments February 27, 1995 letter to Santa Clara Valley Water District Draft EIR For Adobe Creek Watershed Project [Commission members only] C, OURTESY,,,COPIES: Terrence A. Neudorf, Santa Clara Valley Water District, 5750 Almaden Expressway, San Jose, CA 95118-3686 Scott Wilson, Santa Clara Valley Water District, 5750 Almaden Expressway, San Jose, CA 95118-3686 Craig Breon, Santa Clara Valley Audobon Society, 22221 McClellan Road, Cupertino, CA 95014 Dena Mossar, 1024 Emerson Street, Palo Alto, CA 94301 Debbie Mytels, 2824 Louis Road, Palo Alto, CA 94303 Libby Lucas, 174 Yerba Center Avenue, Los Altos, CA 94022 Linda E-lkind, Town of Portola Valley, 765 Portola Valley Road, Portola Valley, CA 94028 Margaret Roper, Biologist, Region 3, Department of Fish and Game, 7329, Silverado Trail, Napa, CA 94558 City of Los Altos, attn. Larry Tong, Planning Director, 1, N. San Antonio Road, Los Altos, CA 94022 City of Los Altos, attn. David Kornfield, Associate Planner, 1, N. San Antonio Road, Los Altos, CA 94022 City of Los Altos Hills, attn. Curtis Williams, 26379 Fremont Road, Los Altos Hills, CA 94022 Foothills College, attn. Bernadine Chuck Fong, President, 12345, E1 Monte Road, Los Altos Hills, CA 94022-4599 Mike Rigney, San Francisco Estuary Institute, 1325 South 46th Street, Richmond, CA 94804 Prepared by:Virginia Warheit A I PCSR I SCVWDEir.sr Page ?~ 11-08-~1~ Project Planner: Virginia Warheit Division/Department Head Approval: Nancy Maddox Lytle, Chief Planning Official A[PCSR! SCVWDEir.sr Pag¢~11 Mitchell Swanson ....... Hydrology & Oe0m.0,rP,ho_logy ’ " ~19 SeabrightAvenue, Suite 210 Santa Cruz~ CA USA 95062 phon~ 408-42~/-0288 - fax 401G427-0472 email MSWA.N @aol.com November 7, 1996 TO: FROM: Virginia Warheit, City of Pain Alto Department of Planning and Community Environment Mitchell Swanson~.~ --’" Comments on Adobe Creek EIR with respect to erosion control and Channel Modifications Dear Virginia, As requested, I have reviewed the Santa Clara Valley Water District’s Adobe Creek Watershed Planning Study - Engineer’s Report and EIR in light of the City of Palo Alto’s conservation policies, specifically the Comprehensive Plan Policies and Programs and the Tree Ordinance. I have organized the following report into recommendations for commenting on the EIR followed by supporting general comments. The City of Palo Alto’s policies call for the protection of riparian habitat, large trees, wildlife habitat and related aesthetic and recreational resources. Much of the environmental quality of Adobe Creek stems from: 1) the occurrence of a canopy of tree cover (both native and non-native species) over the Creek; and 2) natural channel bed and banks. These resources are directly affected by the proposed project. The City’s policies appear to emphasize an "avoidance of impacts" approach to planning flood control measures rather than the "minimize impacts" approach that has been taken in the EIR. In this regard, the primary task in this review is to determine whether feasible alternatives exist to meet flood control and water quality objectives while avoiding impacts to Adobe Creek’s natural resources. I conclude that there are many opportunities to avoid impacts and achieve the basic objectives of the District and the City. These may be realized by conduc.ting intensive site-specific analyses, and by incorporating principles and concepts of fluvial geomorphology (the scientific study of stream channels and the processes that form them). Furthermore, where treatments are likely needed, I f’md that there are suitable alternatives that reduce impacts and provide greater opportunities to restore resources on site. To achieve such "optimal" solutions, I propose that the following recommendations be included in the City’s comments on the EIR: 1)Implement a mitigation program that incorporates an impact avoidance approach to planning specific design solutions for individual sites. This would be accomplished by conducting field and rese. arch analyses during the construction plan development. The ~L.~’8 LE~ 8817 : "ON BNOHd 90-]OHdblOW099 AgO-!Ob!(IAH NOSNUFIS : NO8-1 Z d NdLE:8 966; "L "AON 3) 4) Hydrology & Geomorpholo~" program’s objectives would include a consensus determination of flood protection meaSures needed on a site-.specific basis, an assessment of the risks associated with various alternatives, and the selection of treatments that best merge the District’s objectives with the City’s policy goals. By incorporating this mitigation measure, the City will gain greater confidence that a site-specific impact avoidance analysis occurs in planning the project. This mitigation program will also help overcome art inherent difficulty of understanding important, site-specific detain and aspects ~f the proposed treatments through an environmental document None. A prime example is the use of habitat acreage in the document rather than a discussion of impacts on specific sites and individual sig~ificam trees which are important to the City’s policies. Conduct further research into alternative bank protection techniques that provide greater opportunities to avoid impacts or to mitigate for them onsite. The emphasis should be on those treatments that best minimize impacts and allow preservation of existing significant vegetation and/or proper conditions for vegetation growth. This would include the use of fabric encapsulated soils, channel bank toe protection instead of full bank slope treatments and other methods of sustaining riparian vegetation. Incorporate a geomorphic analysis of the proposed sites to: a) determine whether the channel is stable biased upon regional stable channel relations; b) assess the channel forming processes and their relation to channel stability; c) identify treatments for site specific problems. Conduct a detailed review of the proposed channel maintenance program to reflect the City’s policies. GENERAL COMMENTS The Adobe Creek planning study proposes channel modifications to enlarge channel flood capacity, install erosion control structures, and update the maintenance program over 7.7 miles of Adobe Creek from Et Camino Real upstream to Moody Road. This portion of the Adobe Creek flows through the communities of Polo Alto, Los Altos and Los Altos Hills. Simply stated, the objectives of the plan are to increase flood protection and reduce potential negative economic impacts due to flood damage while protecting the environment, mitigating significant environmental impacts and integrating the desires of the affected communities. Other objectives include water quality improvement and protection of water supplies. The inherent quality of Adobe Creek in the City of Palo Alto is also affected by activities (current and proposed) in the adjoining communities. An important example occurs just upstream of El Camino Real where large oaks occurring on the south bank of Adobe Creek in the City of Los Altos shade the creek on the City of Paio Alto’s north side. Accordingly, the review I have conducted extends beyond the City limits. ELPO LEP 80~ : "ON BNOHd 90qOH<:I~OW099 AgO-IO~,kH NOSNUMS : WOmB E d WdLE:8 9F:~61"L "AON Swanson Hydrology & Geomorphology Identi~ing the Problem and Its Causes: Where is Treatment Needed? Bank Erosion The EIR presents a wide range of options for treating flood related problems a~ individual sites. The problems may fall roughly into erosion control measures for ch~nel banks and the channel bed, expansion of channel flood capacity and exp~sion of the District’s maintenance activities to remove obstructing debris and sediment. To identify erosion problems and the causal processes, .judgments must be made regarding the stability of the existing channel. One aspect of channel stability is the geomorphology of the stream which encompasses the natural processes of sediment deposition and erosional processes of the channel in question. Lri Adobe Creek, a canopy of shading trees and dry soils in summer months often results in bare soil banks. Trees grow on or atop the bank. Although the appearance of bare soils may immediately indicate a batik erosion problem, the bank may actually be stable becaiise overall channel width is adjusted to the erosive forces and its "bareness" may be more related to plant growing conditions ra~er than stability. If stable width exists, the chances are less that a problem exists and the impacts aiad expense of treating the problem could be avoided. Bed Erosion, Scour and Degradation A second problem identified in the El!{ is channel bed stability. Lowering of the channel bed due to downward erosion can undermine banks and infrastructure such as bridges, pipelines and bank protection works. Bed lowering where the bed meets the channel baxtks is a common cause of bank erosion. Long term bed erosion is termed "channel bed degradation" and is often a response to land use changes and modification of the stream by development. "Scour" is the .short term lowering of the bed during a flood due to hydraulic erosive forces of flow. A judgment must be made to determine ff bed stability at a particular site is a signLficant problem and whether it should be addressed at an individual site or over an entire reach. For a specific site, treatment may involve simply providing erosion protection at the toe of the bank which would not involve greater impacts in most cases. Using grade control over an entire reach my be more destructive, could lead to negative changes in hydraulics and channel stability, and may not relieve short term scour. Treatment of Specific Sites rather than entire Reaches In general, the Adobe Creek Plan proposes treatments over fairly broad reaches where significant problems may only occur over a fraction of the reach. The location of an erosion problem may be related to a short reach where the trajectory of flow attacks the outside bend of a bank. In the Adobe Creek Plan, concerns over hydraulic continuity of HYDROLOGY / GEOMORPHOLOGY / WATER RESOURCES / F.~NTIRONMENTAL PLANNING Swanson Hydrology & Geomorph~logy the proposed stinlcture dictate that banks adjacent to unstable sites are treated in the same manner as those that exhibit stability. Some impacts may be avoided and flood protection objectives achieved by reducing the treatments to only those areas where it is absolutely needed. In addition, some alternative ti-~atments, such as projecting hard points of rock, may reduce the risk that hardening one bank could cause erosion in an adjacent site.;- A second set of actions involves replacement of existing substandard or failing erosion protection structures. In some cases these are obviously failing and require repair or replacement. In other cases, such as the vertical concrete wall located about 200 feet upstream of the El Camino Real crossing, replacement is occurring because the type of structure is not a conventional treatment. Some of these older structures are stable and support significant trees or stands of vegetation. Where older structures support significant resources, remedial installation of toe protection could avoid impacts and provide the necessary erosion controI function. Erosion Treatments Bank Erosion Bank erosion is often treated by increasing the resistance of the bank to erosion. Bank erosion often results from the erosion at the toe and mass failure of the upper bank. Often the hydraulic forces that cause overall bank failure are concentrated just a few feet above the channel bed. Thus, in many cases, toe protection may solve many problems where full slope bank protection is proposed: This would help avoid impacts and also provide vegetative opportunities. The EIR places limits on vegetative treatments in bank protection structures based upon slopes greater than 2 horizonta! to ! vertical or projected flow velocities greater than 6 feet per second. There are technologies that can support steeper slopes using encapsulated soils and plantings. These treatments can involve more expense, but when combined with toe protection, they may be comparable in expense and effectiveness. Attachment A provides an example of the use of fabric encapsulated soils. Bed Erosion Treatment of bed erosion can range from a limited "grade control" of rock across selected portions of the channel bed to full-scale lining of the channel over an entire reach. Grade control can take many forms from vortex rock weirs to concrete lining. Grade control can be useful in reducing the need for bank repair and can be aesthetically pleasing. Wholesale lining can be destructive and expensive. It is important to use grade control structures sparingly and only when absolutely necessary. Placement of grade control affects the local channel slope and the dynamics of channel bed scour and sediment transport resulting in channel instability. Site specific geomorphic analysis can help ascertain whether grade control is necessary ~d whether HYDROI..OGY / G~OMORPHOLOGY / WATER ItESOUR(~S I ENVIRONMENTAL PLANNING Swanson Hydrology & Geomorpholog3~ 11/071~ , _ ~age other treatments, such as extending bank protection below the channel bed, are just as effective. Mitigation Opportunities As described above, the City’s policies dictate an impact avoidance approach o~/er impact minimization. Where treatments are needed and avoidance is not practical~ the next strategy should be to mitigation "on-site" and "in-kind" in terms of habitat. The mitigation usually involves planting trees to replace those lost to the treatment. The opportunities to plant trees within a bank protection structure is highly dependent upon the selected treatment. The mitigation recommendation proposing geomorphic analysis and research can help realize these opportunities. .........................LOd -RESHYDROLOGY / GEOMORPHO ~ / WATER OURCES / EN AL PLA.NNING Palo Alto Februa~’ 27, 1995 Planning Di~ion TerTy A. Neudorf, Environmental Planner Santa Clara Valley Water District 5750 Almaden Expressway San Jose, CA 95118-3686 Subject: Adobe Creek Watershed Project-- EIR Notice of Preoaration Dear Ten-)’: Thank you for the opportunity to respond to the Notice of Preparation of the Environmental Impact Report for the Adobe Creek Watershed Project. The Cib’ of Palo Alto has a keen interest in Adobe Creek, which forms the southern boundary of our city and is one of three remaining creeks in Palo Alto still in a natural condition along all or part of its length from the Foothills to the Bay. All or part of Reaches 1-5 of the proposed project are located within the City of Palo Alto. In addition, the cib’ is concerned about flood control and environmental issues along the entire length of the creek corridor. The City Planning Department and the Public Works Department submit the following comments for consideration in preparation of the project EIR: The design and implementation ptan for replacing the existing culvert under El Camino Real and rebuilding the upstream and down stream transition structures need to be developed in coordination with the City" of Palo Alto for two reasons: 1) This location is the gateway to the city from the south and is identified in the city’s Comprehensive Plan as the location for a specially’ designed gateway feature. The city views the proposed replacement of the culvert as an opportunity to design a special entry to the city in this location and would like to work with the SC\r~VD to accomplish this; 2) The city is currently reviewing an entitlement application for the redevelopment of the Hyatt Hotel site on the north side of Adobe Creek at El Camino Real. The redevelopment project will need to address issues such as creek setbacks, access, planting along the creek, coordination with the city gateway feature, and traffic issues during construction, all of which will need to be coordinated with the Water District’s plans in this location. Consider the effects of the proposed reconstruction of the El Camino Real culvert on local businesses and residents during construction (e.g. loss of on-street parking, reduced visibility of storefronts and business signs, noise, dust, etc.). P: \S H.-\R E,.S C \~,\’D. LT R l~) Ftami!ton Avenue P.O. E, ox 1 tr2.50 t’ak~ Alto, CA 943d3 4!5.329.2441 Conduct an ambitious public information campaign to notify" loca! businesses and residents about the proposed project. Coordinate with the City’ of Palo Alto’s Planning Department to determine the review process and schedule for the Environmental Impact Report and of subsequent implementation of the various phases of the project. Adobe Creek is identified in the city’s Comprehensive Plan as a natural resource and wildlife habitat area, and the Plan calls for the protection of.these resources. Intervention should be conducted in a way that does not interrupt the continuous natural riparian corridor or reduce the habitat value of this vep,’ important natural system. Alternative methods to accomplish flood control and bank stabilization with the least impact on natural habitat should be used. Several project descriptions indicate gabion baskets are proposed. While some plants may’ be incorporated for an aesthetic effect, use of gabions generally’ does not allow for establishment of a natural riparian habitat, particularly the number and variety, of plant materials essential to sustain a natural riparian system. Biotechnical creek intervention techniques should be used that leave existin~ riparian trees and shrubs alon_o the creek banks in place wherever possib!~, and where banks must be altered and plants removed, a continuous high quality natural riparian system reestablished. Such techniques have been used successfully in the Bay’ Area and in other parts of the country.’. The project description indicates a use of herbicides in the maintenance program. Trees and shrubs along the banks of natural streams shade out undergrowth within the stream channel, thus helping to keep it clear for flood water conveyance. Design alternatives that replicate natural systems and reduce the need for herbicides should be examined. Again, thank you for the opportunity’ to comment on this notice of preparation. Please feel free to call me if you have any questions regarding our comments. We look forward to working together with you on this project. Sincerely’, VIR~ARHEIT Senior Planner (415) 329-2364 cc:Plarming Director, City of Los Altos Mike Rigney, Coyote Creek Riparian Station Ken Schreiber, Nancy Lytle, Jim Gilliland, Sarah Cheney, Lisa Grote, Joseph Colonna, City., of Palo Alto Planning Department staff Joe Teresi, City’ of Palo Alto Public Works Engineering Division P:.Sl [ARE’,.SCVWD.LTR DEPARTMENT OF FISH ~,qD GAME PCST C;;~CE BOX 4T ~707) Mr. Sam Herzberg San Mateo Count}, Planning Division 590 Hamilton Street Redwood City, California 94063 Do~-toqa Val!=v Tra4~4 ~_~_n~ Center Rezon~ Stable Permit, anG Grading Permit N_g=;ive Declaration (SCH #96082033), San Mateo Count}, Department of Fish and Game personnel have reviewed the Porto!a Valley Training Center Negative Declaration (ND) Mitigation Plan and Restoration Project. The project proposed "after-the-fact" rezoning of portions of the project site; amendment and renewal of an expired stable permit, including construction of additional facilities and "after-the-fact" approval for already constructed facilities; and "after-the-fact" approval for roadway construction in which 80 feet of creek was cu!verted. The project site, !ocated on Stanford University Land, is bordered on the east by Alpine Road, on the south and west by Junipero Serra Freeway, and on the north by the Stanford Linear Accelerator. The Project Desc_~4_D~_o.-~ section under Roadway Components (page 3-~) describes construction of t~=..~ roadway, s=m~=nts indicatinm ~.u,,D~_ ~’ =~ o:- =~=~ .... of ~==k cuiverted and depth of cut and z4qq TH=~= is no descr:Dtion of- ..........’~n~ area of either w~anG acreage filled or the Area of riparian corridor impacts that resui"=s~ from the various road segment consnruct{o~s_ ~. . Department personnel observed significant riparian impacts as a result of construction of Roadway Segment IiI. However, there is no descrip~-~_on or those impacts or others associated with previous unpermizted cu!vertinm of the creek. The ND should be amended to include a desc~{st{o~ an~ acreage of wetland and riparian areas immacted by these already completed roadway projects. in the same section under Sediment Pond (page S) it states tha: "sediment removal wil! be limited in scope and wil! be used solely ~o mainnain a narrow channel through the pond area to the culvert," and that "the intent wil! be to minimize any disturbance to the remainder of the creek, which will be restored :me." There is no description in the ND of how or when this creek res:oration wi!l occur. Since this creek has been impacted b’f the project, the Denarnment n~=~=~s on-=~= in-kind ,.~zma . _, ~_:= ....=notation is :or and/or z: this res~= ....could nar=iai!v or full<, mitic=,= i~ :his and mast unnerminned and u--~igaced ~ ....~m t~e~ this ~= .....= ~ should be ~nc±uee@ in the N~. in the same sect~~’ ’,on under Pronose4 Mitmoa<~on Measures <name E) mc s~=~_s znat as m,~_gacion rot the <00 feet of creek that has been cu!verzed to date withoutD~_m_~~=~ 4" approval_0 the anmiicanz and properny owner have submitted a proposed wetland mmt~mac~on measure on the }[ebb Ranch p_op~_ty !oca-=4 adjacent to n~ Center, on lands of Stanford Land Management." in__v_~=- ~=-.,~g the San Francismuito C~e=~, .... Restoration Project an Webb Ranch, the Department also finds information !ackinm The nronosai to clear scan in-s~ream crossin~ used by vehicles and horses, will improve wa~er Guaiity and reduce erosion. However, use of gabion structures an~ Reno mattress does not promote_ ~_,_Da~__an.. vegetatmon ...[<ownn, nor @oes mn promote sumta~le chance! suDsnrate or esnab!ishment of a !ow flow channel for fish; immortant steeihead ~=~ac elements, it is not clear in t~e mitigation plan how many feet of bank wil! be impacted by the construction of gabions, which presumably serve as a footing for the clear span brid~e. Also, ~ is not clear how many feet of Reno m=~t_ess is proposed for the channel bottom. The plan should be amended to include this information. !n the Restoranion section under Revegenation Plant Communities, the ND snares tha~ "soil wil! be introduced to the stone ,,= .... .. ant c!=--=~ with na~~,~ ~=n~_: -~--:=~ ~n=~=s " Gabion =~no.~ herbaceous,, =~ mesc,weedy v=a=cation c=~=n-, :~ the structures sumoorc woody rioari[n smecies The c©.z~en~s ~lnl~lZl~g c~e gaDlon scr~ccures anQ ~eno mattress anc uszn~ ~zoremed!at~on technzques to restore the a_m~a~_a banks. The mitication ~lan fails to identify the quality and cuancicv of "=-~<,~::anc~,_=~--ion and rimarian. ~v~gec~= = -acion. Both of these micimacion components are correlated to the c~e and area of impacts to each = "" -o ~n:.hanitats, which remain unaddressed in :he ~;D. The Demartmen~ ~=commends no net loss of either wetland _=n~ hab value Mitigation for !ost wetlandsacreage or wet7- ~fiat . cr creeks must include the .creation of new wetlands on at least a :! basis r~ ~=~ -.’aiue wetlandsv,~u_@ .......... ..... ire n~c~=~ ratios for compensation, in the case cf rimarian imaaccs, the Department re:smr.ends chac imcaccs be micicaced =or =~ = 3:: ~:-io by clan should m= -~=~:=~ ts inc!ude the a-~=~=es -= :.=-hand creation and ri~ari= September 6, i996 Page ~ ~ the mitimation plan fails to define a :~4 ~ ~ -" associated success five -~:~ fo!iowinm success c_:t ....:(=) years with ~=~ At the end of three 3) years there wil! be 80 percent or greater survival.If at the end of three (3) years there ~s less ~ha~. 80 mercenz survival, all dead plants wii~_ be re~iaced and a contingency_ . ~!an_ co.~.n~~=~-~ maintenance mrob!ems shall be submitted to the Department. At the end of five (5) years there will be 80 percent surviva!. The mitigation-plan should be amended to include a monitoring plan with success criteria. ~m.y work within the banks of the creeks, including road crossings_ , culverts, and s~_m_n~~ ~ - removal wi~__ require a streambed alteration agreement with this D~oa.~me.~. The Department has direct jurisdiction under Fish and Game Code sections !60i-03 in regard to any proposed activities that would divert or obstruct the natura! flow or change the bed, channel or bank of any stream. We recommend ear!}, consultation since modification of the proposed project may be required to avoid imoacts to fish and wildlife resources. Forma! noti=ication of proposed channe! modification under Fish and Game Code Section !603 should be make after all other oermits and certifications have been obtained. Work cannot be initiated until a strea!nbed alteration agreement is executed. Since California red-legged frog, a Federally listed soecies, is present in San Francisquito Creek, the Department recommends that the project applicant contact the U. S. Fish and Wildlife Service (Matt Vandenberg at 916-979-2725) in addition to applying for a streambed alteration agreement with the Department. ~=..~. Department _{s- conc=~n=~_..._@ with the aoo!icanz’s_, continued aooroach to "after-the-fact~’ oermittins VmDacts to resources t~a~., occurred vears, amo_ make _~t difficult to ademuate!v_ . ~_m~n~~=~=~ ’ what t~=.._ extent of those imoa~ts- we._~= and, therefore, make it d~;~-dete = ade~uat= mitigation.~ - ~-~~ul~e .....g that {- ~990 and subs=~" =-- to th~: time not only impacted -~= stream and rioarian ~= ....... s -~=~ but ~av= ~-~-= .... ~ to impac- -~=~ ore~ ": = ~’~= -~ -~= lack cf mitigatien. ~= ~mD~_=. loss a!so factors into what the=pp.op__=~- ~ ~{--= mitigation should be. Mr. Sam Herzberg September 6, !996 Page Four At this time, the Demarzmena cannot a_~=-~e_~{~-LL~_..= whet~=~ ....the ND and mi[igation p=a~ is asequate due :o ~h_ lack of c_ ~ information. Therefore, the recommends cerzification of the ND unt~l which time, ~h~ documenz is amended to include all the information requested above. if you have any Guestions, please contact Margaret Romer, Fishery Biologist, at (408) 842-8917; or Car! Wilcox, Environmenta! Services Supervisor, st (707) 944-5525. Sincerely, Brian Hunter Regional Manager Region 3 Mr. Michae! Thabault Ms. Kelly Geer 3310 E! Camino Avenue, Suite !30 Sacramento, California 95821-6340 ~.~s. Virginia Warheit City of Palo Alto Planning Department 250 Hamilton Avenue Pa!o Alto, California 94301 November 18, 1996 LINDA V. ELKIND 14 Hawk View Portola Valley, CA 94028 Chairman Bern Beecham and members of the Planning Commission Palo Alto City Hall 250 Hamilton Ave Palo Alto, CA 94301 Re: Response to the Santa Clara Valley Water District Draft EIR for Adobe Creek Watershed Project. Dear Chairman Bern Beecham and members of the Planning Commission The purpose of this letter is to urge that you recommend that the city council direct the city staff to forward staff comments on the Santa Clara Valley Water District Draft Environmental Impact Report for the Adobe Creek Watershed Project to the SCVWD. The staff’s report and comments and the "Attachment A" prepared by the city’s consultant should be submitted to the SCVWD. The comments point out many important precedent setting approaches to creek corridor management and flood control. One particularly important point is the need "to preserve the ecological balance of the indigenous biotic communities and to maintain plant associations and wildlife habitat". This can only be achieved if the city avoids further impacts and requires that habitat impacts be mitigated on-site and "in- kind". It is particularly important to point out that the opportunities to avoid impacts depend upon conducting "site-specific analyses and by incorporating principles and concepts of fluvial geomorphology (the scientific study of stream channels and the processes that form them)." Please support the staffs comments about the adequacy of the proposed mitigation approach. Important issues raised by staff include: 1. Mitigation sites are not in Palo Alto 2. Mitigation site credits fail to reflect the incremental increase in habitat value of the sites. 3. Failure to include success criteria for Revegetation of the mitigation sites. Mitigation fails to succeed in many cases, because no criteria for enforcement are adopted. 4.Mitigation measures should provide continuity along the corridor and among the three types of habitat which function as parts of an interreiated ecosystem. As al! of our towns struggle with the continued demands ol urban development, it becomes essential that each community works together to protect and preserve the ecological integrity of the corridors within our jurisdictions. Palo Alto’s staff has shown particularly thoughtful and informed efforts in this area. Dena Mossar Santa Clara County Creeks Coalition 1024 Emerson St. Palo Alto~ CA 94301 November 12, 1996 Bern Beecham Palo Alto Planning Commission R ECE_~VED NOV 0 1996 Department ot Planning and Community Environment Bern I am writing to encourage you and the members of the Planning Commission to endorse the staff proposal that you recommend that City Council direct staff to respond to the Santa Clara Valley Water District Draft Environmental Impact Report for the Adobe Creek Watershed Project. The city’s response should include the comments recommended in the staff report and in Attachment A prepared by the city’s consultant. Staff and the consultant have completed a thorough review and given a well- reasoned .response to the EIR. As the funding for flood control projects dries up, it becomes increasingly important for the water district to work cooperatively with all cities in each watershed. Staff’s recommended comments are in keeping with this imperative. I have attached a copy of the "Strea~side Planting Guide for San Mateo and Santa Clara County Streams" for your personal reference. This booklet was developed by the Coyote Creek Riparian Station to guide citizens, city staff and policy makers in creating viable riparian habitat in both urban and rural areas. Thank you for considering our request. Sincerely, for the Santa Clara County Creeks Coalition Members, Palo Alto Planning Commission Santa Clara Valley Audubon Society Committee for Green Foothills Peninsula Conservation Center Sierra Club, Loma Prieta Chapter Bay Area Action Coyote Creek Riparian Station San Francisquito Creek Watershed Coordinated Resource Management Plan (CRMP) Mitchell Swanson Hydrology & Geomorphology 519 Seabright Ave. Suite 210, Santa Cruz, California 95062 Phone 408 - 427 - 0288 Fax 408 - 427 - 0472 ernail rnswan @A OL. COM Resume of Mitchell L. Swanson QUALIFICATIONS Mitchell Swanson has over fifteen years of consulting experience in hydrology, hydraulic studies, geologic hazards, and geomorphology related to restoration and resource management in rivers, streams, coastal estuaries, and wetlands. This experience includes the development, management and completion of comprehensive technical and planning studies for a full range of private and public sector clients. Mr. Swanson specializes in the development of technically and environmentally sound management and restoration plans for rivers, estuaries and watersheds. These studies often involve the coordination of many disciplines by Mr. Swanson including biological sciences, hydraulic engineering, land use planning, economics, landscape architecture and environmental planning. In the present era of conflict between environmental regulation and society’s need for flood control and utilization of water resources, Mr. Swanson has become a recognized expert in conflict resolution between governmental agencies, and public and private interests. Mr. Swanson has brought international expertise and management techniques used by public water resources agencies in England and Germany to help resolve problems faced by flood control engineers and resource agencies in an era of strong environmental regulation (the Clean Water Act, California Resources Code enforced by the California Department of Fish and Game and the Public Trust Doctrine). Mr. Swanson has extensive expert witness experience having appeared before the California State Water Resources Control Board and Board staff, California Superior Court, and the U. S. Congress. Mr. Swanson has testified with regards to hydrology, flood control, resern, oir operations, hydraulics, geomorphology, and environmental impacts. Mr. Swanson’s technical expertise includes historical geomorphic and hydrologic studies for geologic hazards assessments (landslides, seismic, erosion, sedimentation, sediment transport and flooding) and in determining the causes and effects of human modification on hydrologic and geomorphic systems. He has extensive field experience in hydrologic and sediment transport measurement, geomorphic mapping and surveying in rivers, watersheds and estuaries. Mr. Swanson has conducted hydraulic and hydrologic analyses using the HEC-- RAS, HEC-6 and HEC-1 computer simulation programs. Mr. Swanson is Principal of Mitchell Swanson Hydrology and Geomorphology, with the office in Santa Cruz. HYDROLOGY / GEOMORPHOLOGY / WATER RESOURCES / ENVIRONMENTAL PLANNING Mitchell Swanson Hydrology & Geomorphology Resume of August 21, 1996 Page 2 Mitchell L. Swanson EDUCATION UNIVERSITY OF CALIFOR_NIA AT SANTA CRUZ MSc. in Earth Science~1983. Thesis and studies in Geomorphology and Hydrology . UNIVERSITY OF CALIFORNIA AT SANTA CRUZ BS in Earth Sciences 1981. Study emphasis on Geologic Hazards and Sedimentary Geology UNIVERSITY OF CALIFORNIA AT SANTA BARBARA Geological Sciences Major 1980. SAINrfA BARBARA CITY COLLEGE Earth Sciences Major 1977-1979. PROFESSIONAL EXPERIENCE CONSULTANT (1983 to 1985, and 1988 to present), Sacramento CA: Present Clients and Projects: California Resources Agency Mining and Geology Board: Hydrologic and Geomorphic Impacts of the proposed Syar Industries gravel mining reclamation plan on the Russian River in Sonoma County, development of impact assessment and mitigation for channel stability, riparian and aquatic habitats; through EIP Associates, Sacramento. Santa Clara Valley Water District: Hydrologic and Geomorphic studies related to flood control maintenance and preparation of a program EIR. California Tahoe Conservancy: Hydrologic and Geomorphic studies related to the restoration design of the Upper Truckee River at the Cove East Marsh. Califomia Tahoe Conservancy: Geomorphic and Sediment Transport Investigation into the Channel Stability Problems of the Cold Creek Restoration Project. Remy, Thomas and Moose: Geomorphology and Planning for settlement of a sand mining permit at the Sandman Site on the San Benito River, San Benito County, CA. American River Coalition: Investigation of Hydrologic Issues involving ~he calcualtion of flood control benefits at Auburn Dam. Past Clients and Projects: Humboldt County Gravel Operators: Acted as technical liaison between gravel miners and the Mad River Scientific Committee and Humboldt County Planning Department. The Nature Conservancy: Prepared a hydrologic investigation of past and proposed restoration projects at the Cosumnes River Preserve, South Sacramento County CA. HYDROLOGY / GEOMORPHOLOGY / WATER RESOURCES / ENVIRONMENTAL PLANNING Mitchell Swanson Hvdrology& Geomorphology August 21, 1996 Page 3 Monterey County Planning Department: Hydrologic Analysis of the proposed Moro Cojo Slough Restoration Plan. The Bay Institute: Investigation of potential fisheries impacts related to Fall flooding of rice fields for rice stubble eradication. U. S Department of Agriculture Forest Service: Development of Restoration .and Watershed Stabilization Plan for Camp Creek, Consumnes River Basin, E! Dorado Forest, CA. East Bay Municipal Utility District: Hydrolo~c and geomorphic studies of the Lower American River pertinent to public trust resources including riparian vegetation and habitat for preparation of expert testimony (Environmental Defense Fund vs. EBMUD) and management plan. Strelow Associates: Hydraulic and Flooding Impacts of the Proposed Bay Avenue Center on Soquel Creek in Capitola, CA. For the Bay Avenue Center EIR. Santa Cruz County Public Works Department: Hydraulic Impacts of the proposed Waste Management and Recycling Center along the Pajaro River, Santa Cruz County CA. California Department of Fish and Game: Reconnaissance assessment of channel substrate on the East Walker River, Mono County California. Santa Cruz County Department of Public Works: Hydraulic, hydrologic and geomorphic studies for stream management and flood control planning, vegetation maintenance and wildlife habitat on the Pajaro River; coordination with the San Francisco District of the Corps of Engineers. Mendocino County Planning Department: Hydrologic and Geomorphic Impact Assessment of proposed instream gravel mining operations on the Garcia River and the development of mitigation and monitoring plans; through Fugro-McClelland (West) Inc. Sacramento Area Flood Control Agency (SAFCA): Development of bank protection plan for the Lower American River and resolution of conflicts and impacts with U.S. Fish and Wildlife Service Resource Category One Shaded Aquatic Habitat. Also, development of flood control alternatives and measures to address environmental impacts along the American River; and development of a flood management plan for Folsom Reservoir. U. S. Fish and Wildlife Service: Fluvial Geomorphology and Riparian Vegetation of the Truckee River, From Lake Tahoe, California to Pyramid Lake, Nevada and the Feasibility of Developing a Hydrology - Vegetation response model. U. S. Fish and Wildlife Service: Interpretation of hydrologic analysis conducted for the Los Vaqueros Reservoir Project by Contra Costa Water District. HYDROLOGY/.GEOMORPHOLOGY ! WATER RESOURCES ! ENVIRONMENTAL PLANNING Mitchell Swanson Hydrology & Geomorphology August 21, 1996 Page 4 Monterey County Planning Department: Investigation of hydrologic and hydraulic desig-n criteria for restoration of Moro Cojo Slough at Moss Landing California. City of Chico: Development of Hydrological Management Plans for the One-mile and Five-mile Dams along Big Chico Creek. Kaiser Sand and Gravel, Inc.: Hydrolo~c analysis of alternative reclamation plar~ for the Pleasanton gravel extraction pits in Alameda County. . Harding Lawson Associates and Zander Associates: Hydrologic and hydraulic analysis of a floodplain restoration plan in the City of Pasadena’s Lower Arroyo Seco Park. Northern California Power Agency: Environmental impact analysis of a proposed dam and stream diversion on Big Sulpher Creek, Sonoma County, for Harding Lawson Associates. Murray, Burns and Kienlin: Geomorphic Assessment of revetment failure along the Whitewater River in January, 1993 for Cochella Valley Water District, Riverside County CA. California Department of Parks and Recreation: Conceptual restoration and channel stabilization plan for Grapevine Creek at Fort Tejon, Kern County. Sacramento Area Flood Control Agency (SAFCA): Technical and environmental impact analysis of the American River Watershed Investigation Report and the proposed Auburn Dam Project. CALTRANS hydrology special studies: Hydraulic, geomorphic and sediment transport studies on Stony Creek in Glenn County for scour evaluation at three highway bridges. Granite Bay Community Association and the California Department of Water Resources Urban Stream Program: Developing a stream management plan to account for flood control problems, protection of riparian resources, and land use planning. Santa Barbara County Flood Control and Water Conservation District: Hydrologic, hydraulic and geomorphic studies for Santa Barbara County Stream Maintenance Practices Environmental Impact Report. Califomia Department of Fish and Game: Assist in data collection and preparation of Lee Vining Creek Instream Flow Study; through Aquatic Systems Research. California Department of Parks and Recreation: Gaviota Creek restoration plan and bridge reconstruction project in Santa Barbara County. Restoration Technical Committee: Technical assistance in coordinating the Department of Fish and Game Lee Vining Creek study with restoration of Lee Vining Creek. HYDROLOGY ! GEOMORPHOLOGY / WATER RESOURCES / ENVIRONMENTAL PLANNING Mitchell Swanson Hydrology & Geomorphology ......... August 21, 1996 Page 5 HMH Engineers, San Jos..e: Hydraulic and geomorphic evaluation of the proposed Porter Street Bridge over Soquel Creek, Santa Cruz County; performed hydraulic and channel stability and environmental analysis for proposed bridge replacement. Santa Cruz County Planning Department: Soquel Creek Flood and Enhancement Study; conduct hydraulic studies of alternative flood control plan, design riparian enhancement plans, conduct public workshops. California Department of Parks and Recreation: Santa Clara River Estuary Natural Preserve enhancement and management plan; development of management procedures for coastal lagoon and wetlands, and restoration plans for impacted salt marsh. City of Santa Cruz CA: Prepared the San Lorenzo River Enhancement Plan for integration of riparian restoration and lagoon management into a proposed U. S. Army Corps of Engineers flood control plan. City of San Mateo CA: Hydrologic and hydraulic studies relevant to stream restoration along San Mateo Creek. State Savings and Mortgage Company, Phoenix AZ: Hydraulic and geomorphic analyses of the proposed mitigation plan for the Harbor Marina Project on the San Joaquin River in Sacramento County CA. California Department of Parks and Recreation, Sacramento, CA: Hydrologic and geomorphic studies for fisheries enhancement plans in 2 Sierra Nevada Streams: Jamison Creek in Plumas - Eureka State Park and General Creek in Sugar Pine Point State Park at Lake Tahoe. U. S. Department of Energy o Federal Energy Regulatory Commission Oak Ridge National Environmental Laboratory, Oak Ridge TN: Geomorphic and hydrologic analysis and research of five streams in the Owens River Basin in Eastern California for cluster impact analysis of proposed hydroelectric projects. U. S. Geological Survey, Tucson AZ: Hydrologic Field Assistant: Participated in geomorphic, hydrologic, and hydraulic studies of sand bar stability and sediment transport on the Colorado River in the Grand Canyon, AZ Gary B. Griggs, Geological Consultant Santa Cruz, CA: Provided professional assistance in preparation of Geologic Hazards Assessments in Santa Cruz County (1983-1987) Robert R. Curry, Geological Consultant Santa Cruz, CA: Provided professional assistance in hydrology and geomorpholob:D, for preparation of expert testimony on Soquel Creek in Santa Cruz County and on the Russian River in Sonoma Count)’ (1984- 1985). HYDROLOGY / GEOMORPHOLOGY / WATER RESOURCES / ENVIRONMENTAL PLANNING Mitchell Swanson Hvdrology & Geomorphology August 21, 1996 Page 6 Robert Ludlow, Attorney_at Law, Santa Cruz CA: Provided expertise in hydrology, hydraulics, and geomorphology for expert testimony on flooding in Soquel Creek and the San Lorenzo River (1984 to 1988). EMPLOYMENT Senior Associate, Philip Williams & Associates, Consultants in Hydrology, San Francisco, CA, 1985-1988. Responsibilities included: designing and conducting technical studies in hydrology, geomorphology, hydraulics, and environmental planning; project management; and marketing management. Projects included: design of environmental restoration of streams and coastal wetlands integrated with flood control and erosion control; management plans for wildlife habitat; technical analyses for preparation of expert testimony; development of field research techniques for mapping and monitoring. Principal, Williams, Kondolf, and Swanson, Consultants in Hydrology and Stream Channel Processes, Carmel Highlands, CA, 1984-1985. Responsibilities included: Proposal preparation for technical and environmental studies, development of field research programs in sediment transport and hydrology, project management, and marketing. Projects included: A plan for the study of sediment transport on the Tuolumne River, CA for the proposed Clavey - Wards Ferry Project (1984); a plan for Preparation of a Master assessment for Gravel Extraction on the upper Russian River near Ukiah, CA (1984-1985). Watershed Analyst II, County of Santa Cruz, CA, 1984. Responsibilities included: preparation of timber harvest plan reviews in Santa Cruz County, planning and supervision of log jam removal crew, assessment of stream erosion problems. Geologic Technician, U. S. Geological Survey, Menlo Park CA, 1984. Re. sponsibilities included: preparation and lab processes of samples for Potassium Argon dating; compilation of maps, aerial photographs and literature for geo!o~c mapping project in North Cascades National Park in Washington state; petrographic studies; statistical analyses of K-Ar. Geologist, U. S. Department of Agriculture Soil Conservation Service, Aptos CA Field Office, 1983. Responsibilities included: MappLng and describing geology, landslides, hydrology, fluvial geomorpho.logy of the Soquel Creek Watershed in Santa Cruz County CA; analyses and description of watershed conditions that lead to flooding along Soquel Creek; data analysis, report preparation; preparation and delivery of presentations at public meetings; development of a watershed management plan. Graduate Teaching Assistant, University of California at Santa Cruz, 1981-1983: Prepared and conducted laboratory and field exercises in geologic field techniques, stratigraphy and sedimentation, groundwater, and geomorphology. HYDROLOGY / GEOMORPHOLOGY / WATER RESOURCES / ENVIRONMENTAL PLANNING Mitchell Swanson Hydrology & Geomorphology August 21, 1996 Page 7 Graduate Research As..sistant, University of California at Santa Cruz, 1981-1983: Conducted research on Groundwater Modeling of the Carmel Valley aquifer, Monterey CA; Gully erosion along the San Mateo County Coast near Pescadero, CA; and field techniques for monitoring erosion and off-site sedimentation in selected California Off-Road-Vehicle Parks in California and complied an annotated bibliography of research on ORV impacts. t Geology Field Assistant, Monterey Peninsula Water Management Distri,ct, Monterey, CA, 1981-1982: Assisted in conducted field topographical surveys, bedload and suspended load sediment sampling, and historical analyses of channel changes along the Carmel River in Carmel Valley, CA. PUBLICATIONS Papers in Refereed Journals Kondolf, G. M., and M. L. Swanson. Channel Adjustments to Reservoir Construction and Gravel Extraction along Stony Creek, California, Environmental Geology and Water Science, (in press). Swanson, M. L., G. M. Kondolf, and P. J. Boison. An example of rapid gully initiation and extension by subsurface erosion, coastal San Mateo County, CA. Geomorphology, 2 (1989) 393-403. Coats, R. L., and M. L. Swanson. Hydrologic analysis for coastal wetland restoration. Environmental Management (in press). Kondolf, G. M., J. G. Williams and M. L. Swanson. Geomorphic controls on channel and floodplain morphology on a steep central California coastal stream (In preparation). Published Papers and Abstracts in Symposia Proceedings Swanson, M. L. 1983. Soil piping and gully erosion.along the San Mateo County Coast in central California. in Proceedings from the second field conference of the American Geomorphologica! Research Field Group. Chaco Canyon, New Mexico, October 7 - 10, 1983. Swanson, M. L. 1985. Subsurface erosion and gully development along coastal San Mateo County, California. EOS 67:955-956 (abs). Swanson, M. L. 1988. Riparian restoration and flood control planning on the Lower San Lorenzo River in Santa Cruz, CA. in Proceedings of the Califomia Riparian Systems Conference, September 22 - 24, 1988, Davis CA. Williams, P. B. and M. L. Swanson 1988. A new approach to flood protection design and riparian management, in Proceedings of the California Riparian Systems Conference. September 22-24, Davis CA. HYDROLOGY / GEOMORPHOLOGY / WATER RESOURCES / ENWIRONMENTAL PLANNING Mitchell Swanson Hvdrology& Geomorphology August 21, 1996 Page 8 List of Unpublished Technical Reports Singer, S. and M. L. Swanson. 1983. The Soquel Creek storm damage recover}, plan with recommendations for reduction of geologic hazards in Soquel Village, Santa Cruz County CA. Unpublished USDA Soil Conservation Service -report to the Santa Cruz County Board of Supervisors (69 pp). Swanson, M. L., 1983. Soil Piping and gully erosion along the San Mateo County Coast. Unpublished Master of Science thesis, University of California at Santa Cruz Earth Sciences Board. Swanson, M. L. and G. B. Griggs, 1983. Hydrologic and drainage evaluation of the Croft Property, Santa Cruz County CA. Report to the Santa Cruz County Planning Department. Griggs, G. B. and M. L. Swanson, 1983. Geologic hazard evaluation of the Isherwood Property, E1 Rancho Drive, Santa Cruz County, CA Report to the Santa Cruz County Planning Department. Swanson, M. L. and G. B. Griggs, 1983. Septic feasibility and slope stability analysis for Stetson Road Property, APN # 90-081-20, Santa Cruz County, CA Report to the Santa Cruz County Planning Department. Griggs, G. B. and M. L. Swanson, 1984. Geologic hazards assessment with recommendations for drainage and erosion control, Parcel APN # 87-171-04, Santa Cruz County, CA. report to the Santa Cruz County Planning Department. Kondolf, G. M., Swanson, M. L., and J. G. Williams, 1984. Plan for study of sediment transport on the Tuolumne River and the effects of the proposed Clavey Wards Ferry Project, Tuolumne County CA. report submitted to the Turlock and Modesto Irrigation Districts. Griggs, G. B. and M. L. Swanson, 1984. Geologic Investigation of the coastal bluff at Place De Mer, Santa Cruz County, CA report to the Santa Cruz County Planning Department. Griggs, G. B. and M. L. Swanson, 198zl. Geologic hazards assessment and drainage plan for the Miller Residence, Happy Valley, Santa Cruz County, CA report submitted to the Santa Cruz County Planning Department. Swanson, M. L. 1985. Contributing causes to the history of flooding along Soquel Creek in the reach near the Highway I crossing. A report to Robert Ludlow, Attorney at Law, Santa Cruz, CA. Swanson, M. L. and G. B. Griggs, 1985. Geologic and slope stability conditions on the Simmons Property, APN # 85-091-56, Riverside Grove near Boulder Creek - HYDROLOGY / GEOMORPHOLOGY / WATER RESOURCES / ENVIRONMENTAL PLANNING Mitchell Swanson Hydrology & Geomorphology August 21, 1996 Page 9 Santa Cruz County. A report submitted to the Santa Cruz County Planning Department. Watson, C., Swanson, M. L., Holland, R., Wade, D., and T. Smith, 1985. Conceptual floodway treatment and landscape management plan for the proposed Laguna Creek Business Park Sacramento County, CA, a report prepared for McCuen & Steele, Developments and Investments and submitted to the Sacramento Count%, Planning Dept. Swanson, M. L., Kondolf, G. M. and J. G. Williams, 1985. Proposal to prepare: Master environmental assessment and background for a gravel management plan, upper Russian River, Mendocino County, CA, submitted to the Mendocino County Planning Department. Swanson, M. L. and P. B. Williams, 1986. Watershed processes and wetland sedimentation in five coastal basins in Sonoma County, CA. report submitted to the California Coastal Conservancy. Swanson, M. L. 1986. Riparian enhancement and sediment management plan for Lower Willow Creek in Sonoma County, CA. Report prepared for the California Department of Parks and Recreation. Swanson, M. L. and W. Vandivere, 1986. San Mateo Creek Feasibility Study - hydrology and flooding, report prepared for the City of San Mateo Parks and Recreation Department. Williams, P. B. and M. L. Swanson, 1987. Tijuana Estuary Enhancement Hydrologic Analysis, a report prepared for the San Diego State University Foundation and the California State Coastal Conservancy. Swanson, M. L. 1987. Geomorphology of the Tijuana River Estuary, technical report submitted to the San Diego State University Foundation and the California State Coastal Conservancy. Haltiner, J., and M. L. Swanson, 1987. Geomorphology and hydrology of the Tijuana River, CA and Mexico, technical report submitted to the San Diego State University Foundation and the California State Coastal Conservancy. Swanson, M. L. 1987. Geomorphology of the barrier beach at the Tijuana River Estuarine Reserve, CA, technical report to the San Diego State University Foundation and the California State Coastal Conservancy. Williams, P. B., Swanson, M. L., and R. Thieke, 1987 Tidal Hydrodynamics of the Tijuana Estuary, technical report submitted to the San Diego State University Foundation and the California State Coastal Conservancy. Williams, P. B. and M. L. Swanson, 1987. Entrance channel closure conditions at the Tijuana River Estuary, technical report submitted to the San Diego State University Foundation and the California State Coastal Conservancy. HYDROLOGY ! GEOMORPHOLOGY / WATER RESOURCES ! ENVIRONMENTAL PLANNING Mitchell Swanson Hydrology & Geornorpholog,v August 21, 1996 Page 10 Swanson, M. L. 19~7, Morphometry of the Tijuana River Estuary, CA, technical report submitted to the San Diego State University Foundation and the California State Coastal Conservancy. Swanson, M. L., Morrison, J., and A. Shepard, 1987, Field report on the Tijuana River Estuary hydrologic analysis, technical report submitted to the San Diego State University Foundation and the California State Coastal Conservancy.. Swanson, M. L. 1987, Analysis of proposed channelization of Mission Creek in Santa Barbara, a report prepared for the Mission Creek Task Force and the California State Coastal Conservancy. Swanson, M. L. 1987, Proposed revision to the FEMA floodway designation in downtown Santa Cruz, CA, a report submitted with technical appendices to the Federal Emergency Management Agency on behalf of the City of Santa Cruz. Swanson, M. L. and L. Fishbain, 1987, Analysis of possible flood control solutions on San Mateo Creek, CA, a report prepared for the City of San Mateo Public works Department. Swanson, M. L. 1987, Analysis of sediment transport and erosion on a proposed floodway on Humbug Creek near Folsom CA. a report prepared for Chuck Watson, Environmental Consultant. Swanson, M. L. and S. Kraft, 1988. Subsurface geophysical investigation of bedrock below the mouth of Pescadero Creek, San Mateo County CA, a report prepared for the California Department of Parks and Recreation. Swanson, M. L. and J. G. Williams, 1988. Field survey report on the Pescadero Marsh Natural Preserve, CA, California Dept. of Parks and Recreation. Swanson, M. L. and P. B. Williams, 1988. San Mateo Creek feasibility study channel treatment alternatives, a report prepared for the City of San Mateo. Swanson, M. L., 1988. Hydrologic changes resulting from the Oneonta Slough dredging project in the Tijuana Estuary, a report prepared for the California Coastal Commission and the California State Coastal Conservancy. Swanson, M. L. 1988. Preliminary assessment of wetlands management for three Central Valley Natural Preserve Sites, a report prepared for the Romburg Tiburon Center for Environmental Studies under contract with the California Department of Fish and Game Region II office. Swanson, M. L., 1988. The Soquel Creek flood protection alternatives study, a report prepared for the Santa Cruz County Planning Department. HYDROLOGY ! GEOMORPHOLOGY ! WATER RESOURCES ! ENVIRONMENTAL PLANNING Mitchell Swanson Hydrology & Geomorphology August 21, 1996 Page 11 Stanley, S., and M...L. Swanson, 1989, The Mission Creek feasibility study: natural channel alternatives, Santa Barbara, CA a report submitted to the Mission Creek Alternatives Task Force, the City of Santa Barbara, and the Califomia Resources Agency - Department of Water Resources. Swanson, M. L., Bradley, N. E., Lyons, K. and J. Stanley, 1989. The San Lorenzo River Enhancement Plan, a plan submitted to the City of Santa Cruz River ~ Restoration Committee and the California State Coastal Conservancy.. Swanson, M. L., and M. Marangio, 1989. The Pajaro River - Santa Cruz Long-toed Salamander Survey, a report submitted to the County of Santa Cruz. Swanson, M. L., 1989. Geomorphology and Hydrology impacts of routine stream maintenance practices in Santa Barbara County, CA, a report submitted to the County of Santa Barbara Department of Environmental Review as part of the administrative program environmental impact report. Swanson, M. L., 1991 The Pajaro River Corridor Enhancement Plan; a report submitted to the Santa Cruz County Board of Supervisors and The California State Coastal Conservancy. Swanson, M. L., 1991. Geomorphic Study of Bed Degradation along Stony Creek, Glenn County, CA; a report prepared for the California Department of Transportation Division of Structures. Swanson, M.L., 1992. Geomorphic and Hydrologic Impact Assessment of the reclamation plans for the proposed Syar Industries, Inc. gravel extraction plan along the Russian River, Sonoma County California; a report submitted to EIP Associates, Sacramento for the EIR and EIS. LECTURESHIPS University of California at Davis (1982) "Progress toward understanding soil piping and subsurface erosion in gully development", given to geomorphology seminar. University of California at Santa Cruz (1984) "An introduction to hillslope hydroloo~, and erosion", given to the Geomorphology class. University of California at Berkeley, (1988) "The history of flood control projects on the San Lorenzo River in Santa Cruz, CA." given to the hydrology class. University of California at Berkeley, (1989) "Important technical and policy considerations in stream restoration projects in California" given to Environmental Geology class. University of California at Davis, (1989, 1990, 1991 and 1992) "The importance of geomorphic analysis and multiple objective planning in designing flood control projects" given to the Rivers of Califomia class in the Geology Department. HYDROLOGY / GEOMORPHOLOGY / WATER RESOURCES / ENVIRONMENTAL PLANNING Item 2 Review and recommend to the CiD, Council comments on the Draft Environmental Impact Report for the Adobe Creek Watershed Planning Study, Santa Clara Valley Water District project. Chairperson Cassel: Do we have additional staff comments? Ms. Lvtle: It might be helpful to explain that the EIR that is before you has been prepared by the Santa Clara Valley Water District as the lead agency. We are commenting on their Draft Environmental Impact Report. The role of the commission tonight is to recommend to the Cit?’ Council what our comments might contain. Staff has put together for you a summary of what we would recommend at this point be included in the comments from the city. That is essentially the point of this item. Virginia Warheit may have something to add. Virginia Warheit: I have nothing additional to add, but am present to answer any questions you might have. Chairperson Cassel: This is not a public hearing item. We are simply making comments, adding those to the comments of the city, and then making a recommendation to the Cib, Council if we so choose. Are there any questions of staff at this time? Ms. Lytle: I would also mention that in our audience are two representatives from the Santa Clara Valley Water District, Scott Wilson and Randall Talley. Chairperson Cassel: Please join us at the staff table. Randall Talley, Santa Clara Valley Water District: I know you have all received a copy of the report, as I can see it up there. (It is three inches thick.) I doubt that you have had a chance to go through the whole thing, but we are prepared to give you a brief summary of the project in Palo Alto, should you desire. Commissioner Ojakian: I have three things I would be interested in. One is that I would be interested in hearing your presentation. Two is having you respond to Mr. Swanson’s vew well written analysis which is Exhibit A in our staff report. Three, if we do have people here who wish to speak even though it is not a public hearing, will they have an oppommity to make comments? Chairperson Casset: I have no cards at this time. Ms. Cauble: It is appropriate, even though this is not a formal public hearing, if you would like to ask if anyone wants to address this item. Mr. Talley: The project in Palo Alto is not that extensive if you look at the entire document. So ZB I PCMin4 ] Min I 1-20.drf Page 1 12-02-96 I would like to ask Scott Wilson, the project engineer for this project, to give you a brief sununary of the elements of the project in Palo Alto. We have some overhead projector items for you, as well. Scott Wilson. Santa Clara Valley Water District: I would like to go over the elements of our study that are located in Palo Alto. The document that you have seen is part of a seven-and-a- half mile study. It is pretty extensive, going all the way from E1 Camino Real to the Hidden Villa trust property. Actually, the elements of the study that are within Palo Alto are not ve~; numerous. The first element is the culvert underneath E1 Camino Real. The current culvert was built over a series of many years, then modified and enlarged, widened, and we found that it was inadequate to convey the one percent, hundred year flow, so we looked at a lot of different alternatives. We finally decided that since it was such a mishmash of different culverts, that our proposal was to replace them with a single new culvert going underneath E1 Camino Real. Upstream of the culvert, the water district has a maintenance ramp which has a lot of erosion problems. There is currently about 100 feet of concrete upstream of the culvert. Our proposal here was to extend gabion protection up to provide the transition to the culvert and stabilize the ramp up to here, which is about 200 feet. We would be removing 100 feet of concrete-lined channel here and this whole bank. which is basically sack concrete slope protection. Commissioner Byrd: I would like to ask, what is a gabion? Mr. Wilson: A gabion is a wire basket filled with little rocks. Mr. Tallev: This is a picture ofa gabion project in the Cit3, of Santa Clara, illustrating the gabion concept. It is a wire basket about six feet long and two feet wide and a couple of feet deep that we fill with rock and we tie them all together. It stabilizes the slope of the channel. This is a picture of the project immediately after the construction and another showing what it looks like a few years later after the revegetation work has been established. That is what is being proposed for the culvert at E1 Camino. Mr. Wilson: Inside the culvert, we are proposing a culvert that is slightly larger than the old one, about two feet wider and a little deeper. One of the features of this is a low-flow channel with fish baffles, should the fisher3.’ ever be restored to Adobe Creek. Beyond 200 feet upstream from the culvert, the creek will be left as it is. The work upstream from the culvert goes for 200 feet, and then it stops and returns to what exists. The other element of the planning study in Palo Alto is some erosion control work along the creek banks. There are six sites in Palo Alto. Three of them are located along Alta Mesa Cemetery. and the other three are located within that area. This is all between E1 Camino and the upstream limit of Alta Mesa Cemetery. Two of the sites are in an eroded area, where we will put ZB ] PCMin41Min I 1-20.drf Page 2 12-02-96 rock riprap, which is just big rocks, at the toe of the bank without any excavation of the bank. A feature of what we will be doing with any type of rock riprap protection is that we will cover the rock and get soil into the spaces between the rocks, and do what they call "joint planting." You take a willow stick or something and stick it into the soil through the rocks. Two of the erosion sites we are proposing are similar to this where it is a more severe problem, so we are placing the rock further up the slope. At one of the sites, we need to cut back the top of the slope because of the situation. At the one remaining site, we are proposing sack concrete riprap. This is not anyone’s particular favorite. It is just bags of concrete stacked together. In this location, there is an Alta Mesa building right at the top of the bank, and it is a very steep bank. There really is no room to do any sort of other protection at this point. That is the extent of the construction work proposed for Palo Alto. The other part of the study is in our planning document. We have come up with a new maintenance program, a progressive maintenance program that starts with the most environmentally friendly and biological method, which works its way up. It starts with planting of plants, then it goes to rock riprap, and then gabions and sack concrete. It is a progressive sort of program which is also part of our plan study that we are proposing. Mr. Tallev: And that is the project. One culvert and six erosion sites. The erosion sites are pretty,, much the routine kinds of things we have been doing for years. Now we are just covering them in our EIR so that they are all covered under some kind of impact evaluation. Commissioner Qiakian: Could you explain a little more about what you intend to do at the area near E1 Camino Real which you called a gateway? That is an area we have talked about considerably over the years here. and an area we have looked at often. Mr. Tallev: We have talked with your staff many times about your gateway project. What we have proposed we hope has coordinated that effort. It is intended to be compatible; we think it is. It is the culvert that Scott described. Is there anything further you need to know? Mr. Wilson: We have talked with your staff about doing the culvert design in such a way that it would work with your gateway plan. whether that be a decorative railing or some parts of the design that would fit with your plan. We have put in our report that the culvert would be designed in alignment with the city’s gateway plan. We did not include a drawing in the report because we did not have one. but we anticipate that we will include an actual drawing in the final report showing our concept of that. Chairperson. Cassel: We have in that plan the redwood trees on both sides. At the present time, we have redwood trees on one side. Will your project cause problems with those redwoods, or will they be able to maintain themselves in their current position? Mr. Wilson: The design of our culvert is done in such a way that the redwood trees downstream ZB] PCMin41Min I 1-20.drf Page 3 12-02-96 of the culvert would not be impacted. Chairperson Cassel: Will the increased speed of the water flowing through that straight culvert impact the side of the bank on the other side of E1 Camino? Mr. Wilson: That side is actually all concrete from E1 Camino and on downstream. What we are doing with our culvert is that we are cutting deeper than the existing culvert, but we are matching the downstream channel. So at the point where the culvert exits into the downstream channel, the velocities will be almost identical, plus, it is concrete. Chairperson Cassel: On the west side ofEt Camino, you are pulling the water faster. What will that do to the banks on the west side? Mr. Wilson: The upstream side? (Yes) Currently, the upstream side is a concrete channel. It is a pretty high velocity channel. Velocities of water approaching bridges do tend to be higher. There is a major storm drain at Los Altos that exits there also, so there is a high velocity there, but the gabions, because of their rough shape, would tend to be no higher than current velocities. Chairperson Cassel: We spent a lot of time on this creek when we were discussing the former Hyatt project. I tend to think of that area as broader or longer than 100 feet. The neighbors on the Los Altos side spent a lot of time here complaining about how their side of that creek was falling in. When I think about its picking up speed, I think about its picking up speed over more than the 100 feet, and that would affect the Los Altos side of that creek, as well as the Palo Alto side. What plans do you have for the Los Altos side of the creek farther up than 100 or 200 feet, say 300 or 400 feet, all along the site of what was previously called the Hyatt Hotel site. Mr. Wilson: The proposed construction for the culvert only goes 200 feet upstream. That is why we have a maintenance program. If there is a maintenance problem and we have an easement, then we do maintenance work. Chairperson Cassel: Then what is going to happen to that section of the wall of the creek that is falling in now? The neighbors are complaining that it is falling in now. Mr. Wilson: Our anticipation is that this culvert would not affect them adversely. That is part of our design. Chairperson Cassel: Let me put it this way. According to the neighbors, that wall currently is being adversely impacted by the stream, so I presume that is part of your program to repair that wall. Mr. Wilson: If it is beyond 200 feet, it is not part of this construction. It would then become a maintenance issue, a maintenance repair. ZB I PCMin41Min 11-20.drf Page 4 12-02-96 Commissioner Schmidt: How tong do you anticipate that the construction of that culvert will take? The reason for my question is that the recent culvert construction took longer than anticipated, and it impacted businesses adversely along E1 Camino. Will this situation be different from that one? Mr. Tallev: I think it would be similar. We would work out a traffic pattern for a detour with the city so that we can get traffic around that site. We have allowed for a three-stage construction so that traffic would not be disrupted. Commissioner Schmidt: Do you know approximately how long construction would take? Mr. Tallev: It is anticipated to take two construction seasons. " Commissioner Schmidt: That is about eighteen months? (Yes) You will work with the city to work out traffic pat-terns. As I recall, traffic was reasonable with the other project, but adjacent businesses were impacted severely. Commissioner Schink: I have a question that relates to Page 7-47. On that page, you show a typical section. In your typical section, you are showing the concrete cutoff wall below the gabions. That is kind of a new detail to me, having reviewed these types of plans in years past. My previous experience had been that the gabions were carried all the way down into the creek bottom. The argument that we heard in the past was that it was better to be consistent and use the gabions all the way down to the bottom of the creek, because then you did not introduce the concrete and the worry, about concrete runoff in the creek and all the other incumbent problems with trying to pour concrete in the creek enviromnent. This is obviously a new approach, for some reason. Maybe you could explain the benefits we get by introducing the concrete cutoff walls over the previous approaches that were used. Mr. Talley: I am not aware of a paving job where we have put the gabions below the invert grade. Commissioner Schink: I don’t know about your doing it, but it was done in some City of Palo Alto projects where we did some creek improvements up in Foothill Park and in some other creek rehabilitation projects I have seen in years past. Mr. Tallev: In the past. we have actually used cross-channel stabilizers that went across the channel ever3/couple of hundred feet to maintain the invert or grade of the channel. What we are proposing here is to let the channel move up and down as it will, but still provide the stability to the gabions on the slope, which is why the concrete slope was underneath the gabions. There is nothing across the channel itself, so it will continue to move up and down in a natural fashion. Commissioner Schink: I understand what you are saying. So in the past you never used it so ZB ] PCMin4 [ Mini 1-20.drf Page 5 12-02-96 that gabions actually worked as the footing and you just over-excavated and installed the gabion baskets down lower? Mr. Talley: I am not aware of any project that the district has done like that. Commissioner Schink: Do you ever have projects where you use this detail where the erosion then begins to expose the concrete cutoff walls and gives it the channelized concrete look? Mr. Taller: No, I have not had that experience, The other channel shown tonight had the cross- channel stabilizers, and they became exposed, but to a slight extent only. Commissioner Schink: In Palo Alto, are you intending to use {he channel bottoms an?a,cay, in addition to the concrete footings? Mr. Tallev: Do you mean the cross-channel stabilizers? Commissioner Schink: No, with the proposed rock channel bottom, in addition to the cutoff walls. Mr. Tallev: In the immediate area upstream of the box culvert, that area will have a rock bottom. In the reach you are looking at here, Reach #11, this would not have one. Commissioner Schink: We would only be looking at the top section. The bottom section really would not apply in Palo Alto. Mr. Tallev: You would not see the bottom section. What you would see is what is in those pictures. Commissioner Eakins: Where does the Los Altos storm drain enter relative to the work you are going to be doing near E1 Camino Real? Mr. Wilson: It is just upstream of the culvert, maybe five or ten feet. Commissioner By.rd: I would like to return to the film you put up that spoke to the one place where you are going to use concrete sacking. I think the phrase was, "It is nobody’s particular favorite." But in this case, it is necessary because the channel was undercut and there was a structure up above. Where is that location? Mr. Wilson: That is at the Alta Mesa Cemetery. It is a slope right below one of their buildings. Their building is literally right at the top of the slope. It is shown on Sheet #7 of the foldouts in the back. ZBI PCMin4 ! Min 11-20.drf Page 6 12-02-96 Commissioner Byrd: My larger question about this is whether the district, as a policy, ever considers land acquisition or working in some way with the landowner of the existing land use that seems to require us to use concrete sacking for channel stabilization so that that land use could change, instead of the concrete sacking being required. Is thought ever given to changing the land use up at the top of the creek bank so that you would not have to go to this extreme measure? I don’t know if that could be considered in this case. I just wondered whether, at a policy level, that is ever considered. Mr. Talley: At a policy level, no. Normally with these kinds of erosion sites, we deal directly with the people who are impacted. We try to work out a solution that is mutually beneficial. Commissioner Byrd: But concrete sacking clearly is beneficial to the land use at the top of the creek, because it prevents the erosion. But for the long-term health of the creek, as your comment indicated, it is nobody’s favorite solution, and that may not be in the best interests of the health of the creek. I am struggling to look for a way to avoid having to take that drastic step. Mr. Talley: What is the option you are suggesting? Commissioner Byrd: I am wondering whether changes in the land use adjacent to the creek are ever considered in order to get around the need for concrete sacking? Mr. Tallev: I still do not quite understand your proposal. Who would need the change in the land use? Commissioner Byrd: Does the district ever negotiate with a landowner adjacent to the creek whose land use requires that the district engage in concrete sacking in order to prevent erosion so that the land use adjacent to the creek might be changed in order to obviate the need to engage in concrete sacking? That could allow a natural erosion or course of events or stabilization that is less extreme. Mr. Taller: We have considered acquisition of the area that is eroding in areas where that appears to be an economical solution. Cgmmissioner Byrd: In this case, was any thought given to alternatives to the concrete sacking? Mr. Talley: This is what fit the guidelines we had proposed. When you have a situation like this where there is a building on top of a bank and it is undercut, this is what is proposed for that area. This is what we worked out with the property ov,~ner. Commissioner Byrd It is unfortunate, as the staff comment suggested, when we have to engage in concrete sacking within the channel. ZB I PCMin4 ] Min I 1-20.drf Page 7 12-02-96 Chairperson Cassel: Have you talked to the owner of that property as to whether that is a building that needs to remain there? The?’ have a building that is sitting on a site that is disappearing underneath it. Mr. Wilson: I spoke to Marilyn Talbot at the cemetery, and I men}ioned this. I did not specifically ask her if this is a building that could be moved. I just talked to her about it and about each individual site and what we were proposing. She did not say anything, one way or the other. I would assume that if it is a building at Alta Mesa that thev are using, they would not want it to be in danger. Chairperson Cassel: Maybe that is an assumption that should not be made. They have a building that has nothing underneath it. so they may want to look at whether the?, need that building. Commissioner Byrd: I don’t mean to beat this to death, but maybe someone on the citT staff could speak to whether or not this was an issue of concern to staff. Chairperson Cassel: Do you want to respond to this now, Nancy, or do you want to respond when we finish other questions of the Santa Clara Valley Water people? Ms. Lytle: That is up to the commission. Chairperson Cassel: Does anyone else have questions they want to ask of the Santa Clara Valley Water District representatives? Then we will return to staff and our consultant. Commissioner Schink: This is, in some ways, a followup to Owen’s question. I notice on your sheets that you discuss that there is a proposed easement line. Are we to understand that this is something new, or are these the existing easement lines? Are you out negotiating for easements? Mr. Wilson: We currently do not have an easement for the area of the erosion site that is shown here. What we did when we made our survey of the creek was to survey the creek for areas of active erosion. There are 17 erosion sites proposed as part of the study. We did not look to see if we had an easement or not. We just said, where there is erosion, we can propose a fix. If the study is approved and it goes forward and Alta Mesa does not dedicate an easement to the district, then we would not do the work. The water district can only do erosion work on lands where it has easements. Commissioner Schink: So to get at what Owen was asking before, you might be in a position to propose a little larger easement to accomplish a gabion solution as opposed to sack concrete. Mr. Wilson: In some cases, that may be the case. In this case, it is proposed because there is an existing building at the bank. ZB ! PCMin41Min 11-20.drf Page 8 12-02-96 Chairperson Cassel: What if the building falls down and they lose the building. Will they pay for the repairs along the creek? Mr. Wilson: They have done some of their own repairs in the past. The other concern at Alta Mesa that Ms. Talbot mentioned to me is that in the older sections of the cemetery, they have put people right up to the top of the bank. They do not want to have things floating down the creek. Chairperson Cassel: You have been talking to us about what is going on in the Palo Alto section. But the rate of flow has a great deal to do with what happens to the Palo Alto section. If you are doing work upstream, the rate of flow will affect what is happening in our section of the stream. Have you made any calculations about the work you are doing and how that will change the rate of flow and how that will impact the banks at the various points, particularly in Palo Alto? Mr. Wilson: The thing with Adobe Creek, a natural stream system, is that with the work we do upstream, each area where we are proposing work is its own section. There are geographic things that control the creek, whether it be a hill or Highway 280 embankment or the Foothill Expressway embankment. There are controls along the creek where the work that we do up at, say, Foothill College is not going to affect the flow down in this section of the creek. Chairperson Cassel: So you are saying that at the end of each section, the flow will be the same as it is currently? The rate of flow of the water leaving that section will not be increased after you finish your repair work? Mr. Wilson: What happens is that in some creeks, when it floods, it goes out of the creek and it goes across the flat lands and into some other creek. With Adobe Creek, there is always a geographic or manmade feature that brings the water back into the creek. So there may be a flood area upstream of Highway 280, but it all comes through the 280 culvert. Chairperson Cassel: Right, but it may come through only at a certain speed. If the opening under the road is only so wide, you can only get so much water under it unless it goes at a greater rate of flow. So you either have to increase the space or the rate of flow or something to get more water down that stream to prevent flooding upstream. You have to find some way to hold that water back long enough for it to go off slower in order to decrease the rate of flow. That is my understanding. Mr. Wilson: What I am saying is that it is not really that way. It is the same amount of water in a natural creek system like this, the creek slope determines the rate of flow. The effect of, say, a channel modification upstream is only going to be affected a few hundred feet downstream, and then it is just going to go back to what it was. Chairperson Cassel: My math doesn’t work that way. ZB I PCMin41Min I 1-20.drf Page 9 12-02-96 Mr. Tallev: If you are familiar with the Matadero or Adobe downstream projects that we have worked on over the last several years, that water actually got out and went away from the channel, so that when we did the channel work, we actually were confining more water to the channel, and then there would be more water downstream. That is why we started downstream to do our construction and worked our way back upstream to take care of that problem. Chairperson Cassel: But the horror we have experienced is a lot of very square creeks. We end up with square creeks because over time, we have not allowed space for a flood plane. Mr. Tallev: That is exactly right. Chairperson Cassel: And if we do not allow space for a flood plane, we cannot slow the rate of slowdown, and if we don’t slow the rate of slowdown, there is no way to maintain those banks. The faster the water flows, the ~eater the erosion on those creek banks. Mr. Tallev: In those projects, we had to squeeze a lot of water through a very narrow area. Chairperson Cassel: In the past, everyone was allowed to build right up to the stream. Are you making plans to change that? What I see here is that you are pushing more water into this creek so that the rate of flow will have to be actually faster to get the water out so that there is no backup upstream. Mr. Tallev: Actually, no. I think that overall, the project will be reducing the area that is going to be eroding away. A lot of the erosion problems in the upstream reaches have been caused because of inadequately reconstructed bride crossings. They were constructed much higher than the natural grade, and they created a sedimentation upstream and a drop structure downstream that just eroded away the banks. This plan proposes to correct all of those artificially induced erosion areas. We will be correcting a lot of that. Commissioner Eakins: Are you striving to create any increased retention areas upstream? Mr. Tallev: Retention was an alternative that we looked at. There wasn’t a site that we could find that would work for us. Chairperson Cassel: Can you hold water in some of the Foothill College parking lots? Mr. Taller: That was an alternative that was looked at, but it did not turn out to be a feasible option. Mr. Wilson: In fact. the baseball field at Foothill College, which we are not doing anything with as it is a perfect flood plane area, is staying as a flood plane. The work we are proposing is farther upstream, and it is going to stay a great big flood plane and do the sorts of things you are ZB [ PCMin4 [ Min 11-20.drf Page 10 12-02-96 talking about. In the report, we took one particular upstream storage site. We took a 10-acre area of land in Hidden Villa trust, and in the report, there is a whole scheme as to how we studied and took the scenario of excavating it ten feet and letting it fill with water. We found out that by the time that got to E1 Camino Real, the difference in the flow was just a few percentage points. It had a very small impact. Chairperson Casset: But over time, the more we create impervious surfaces and the more we build, the more water that has to flow into that creek. I read all of your policies and goals at the beginning of the report, but I do not see anything in there indicating that one of your goals is to decrease the amount of impervious surface and to find little flood planes where you can hold water so that it does not continue to increase the problem. Mr. Tallev: Are you talking about new, future development increasing impervious surfaces? Chairperson Cassel: Yes. we have been building and building, and every time we build something, we create more impervious surface. Mr. Tallev: Every time we review an EIR, we make that comment and send it back to the city,. Chairperson Cassel: What else are you doing in terms of keeping people from building up near the creek? We have done some work, and we keep getting what I consider to be fairly liberal recommendations from you or from someone as to how close people can build along the creek edges. Mr. Tallev: We have been encouraging all of the cities in the county to have a building setback from the creek. Some of the cities have adopted that. I am not sure what Palo Alto’s setback is. If it is within 50 feet of the creek, we review it to ensure that it is not impacting the creek. If it has no adverse impact on the creek, we will issue a permit for it. Chairperson Casset: Sometimes, we receive them, and they have been only 25 feet from the creek, and we have been looking at possibly keeping a 50-foot space. Mr. Tallev: What is the city’s setback requirement? Chairperson Cassel: It depends. We have had situations where there have been options, and we have been looking at them here at the Planning Commission because it is a special circumstance. You have given them a much smaller allowable space, like 20 feet. Mr. Tallev: But doesn’t the city have a setback? Chairperson Cassel: Yes, we do. ZB ] PCMin41Min 11-20.drf Page 11 12-02-96 Commissioner Schmidt: I believe that in the new Comprehensive Plan, we are recommending 100 feet. Chairperson Cassel: I am just trying to see how hard you are pushing, because this is such an urgent problem. This goes a long way back for me, because the night Richard Nixon was resigning, I was sitting in at county board offices giving testimony on the necessity of allowing flood planes. Seeing no further questions for the Santa Clara Valley Water District representatives, we can now hear from our consultant. Ms. Warheit: Our consultant is Mitchell Swanson, a hydrologist and geomorphologist with a great deal of experience. I -know some of you have received his resume. We were very fortunate to obtain his services in reviewing this project. He has many things that he is bursting to tell you. There is one thing I would like to address first before getting to his comments. It is in regard to the matter of gabions and what they are and about their lack of environmental qualities. I would start by quoting from the EIR. On Page 77, this EIR clearly identifies gabion baskets and riprap as types of bank treatment that have no habitat value. I want to quote from two places in the EIR that says that, and I have some additional information from the Department of Fish and Game that shows their taking the same position on another project. On Page 77 of the EIR, it says, "The riparian habitat is a biotically significant and increasingly scarce resource in California." Further down, it says, "The loss or denigration of any mixed riparian forest within the riparian corridor due to vegetation removal or the placement of gabions or riprap from the project is a significant impact." On Page 81, under Resurfacing of Soil Channel Banks, it says, "Project construction involves the installation of gabions, riprap, sacked concrete slope protection and geocell along the creek banks. The placement of these "hard" materials would result in a loss of native substrate, e.g. soil, and would inhibit the establishment of all native vegetation, both landscaping or natural recolonization. This reduces the potential for reestablishment of riparian habitat on the channel bank and further lowers habitat values for wildlife. The net loss of native soil channel banks from resurfacing with gabions, riprap, sacked concrete and geocell is considered a significant impact." So proposing gabions as somehow an okay solution isn’t accurate. The material I passing along to you is a letter written by Margaret Roper, a fisheries biologist for the State Department of Fish and Game where she is responding to another Negative Declaration in September for a project proposed at the Portola Valley Training Center on San Francisquito Creek. On Page 2 of that letter, she reaffirms that the Department prefers, "on-site, in-kind mitigation". Later in the letter she says, "Use of gabion structures and Reno mattress does not promote riparian vegetation growth, nor does it promote suitable channel substrate or establishment of a low flow channel for fish." Further on, she says, "Gabion structures, at best, support herbaceous, weedy vegetation. Rarely do the structures support woody riparian species. The Department recommends minimizing the gabion structures and Reno mattress and using ZB { PCMin4 { Min 11-20.drf Page 12 12-02-96 bioremediation techniques instead to restore the eroded and otherwise degraded banks." So it is because of our awareness of that that we raised questions about the use of gabion baskets for 200 feet along both sides of the creek upstream from the E1 Camino Real bridge. We raised that issue two years ago in our response to the Notice of the Preparation of this EIR. The letter raising that issue is included at the end of the EIR with the responses. We have two concerns tonight. One is that it seems to be well established in the environmental community that gabions are not an acceptable environmental solution when you have alternatives. Our concern was whether environmentally sensitive alternatives have been sufficiently explored in those locations. Beyond the environmental concerns, there is an aesthetic concern, since this is an identified, important city gateway. The district has been very cooperative with us and has had meetings with us over two yealrs about working together on a design for the bridge. They have agreed to work together with with us if the city pays the incremental increase in cost to have a well designed and handsome bridge at that location that would tell people they are entering our city. But if we were to put hundreds of thousands of dollars into this bridge, and then while standing on the bridge, what you would see upstream for 200 feet are these gabion baskets, you will never recreate the appearance of a riparian stream. So there are both aesthetic and environmental concerns about that. A third concern about the proposal here at E1 Camino is that downstream, the EIR identifies no trees that would be impacted by the project. It has also missed a few upstream. The largest tree upstream, a 50- or 60-foot-high black locust near the existing ramp would clearly be right in the middle of the construction project. It is not identified, so I do not know what else might have been missed. I was out there recently with Joe Teresi, and we saw several small oaks that are more under-story sized trees, and probably were invisible when all of the leaves were on the trees and all of the blue elderberry, were in full leaf. You probably could not see these under-story small oaks, but there are some out there, and there are no oaks identified as trees that would be removed in the project. None of the trees downstream are identified as being removed, and I understand that maybe the work downstream will only go another 35 feet or so, but when you are standing there, it is very clear that there is actually a young oak within inches of the bridge railing, so clearly it is in the area of work. There are three large redwood trees may not be precisely in the exact area of new construction, but they are clearly close enough to the new construction that it is hard to imagine that with the entire bridge being removed and new construction going in, that those trees would still be standing. There certainly is a concern about their health during that kind of a process. So those were the concerns that we saw relating to the E1 Camino site in the EIR. Commissioner Byrd: Virginia, I understand that your comments on the gabion baskets seem to speak to the issue of the concreting. I was wondering why that was not also explicitly surfaced by staff?. Is it a concern to staff that there Will be additional concrete sacking near the Alta Mesa Cemetery? ZB ] PCMin4 ] Min I 1-20.drf Page 13 12-02-96 Ms. Warheit: It is such a big project. We observed that sacked concrete was proposed in that location.. The water district has another EIR under preparation right now that will be coming out later. It is their maintenance EIR, an Environmental Impact Report on their general maintenance proposals and how they will do their maintenance over the next ten years and beyond. It was not entirely clear to us the extent to which the maintenance issues are being covered in this EIR or whether they were coming later in the other EIR, even though some maintenance projects were identified in this document. Our general concern about the erosion control work is that while they include a repertoire of many types of bank stabilization options, including just stabilizing the toe, and others that we are very happy to see, ones that incorporate plant material and that take an approach of having minimum impact, the criteria for using those are so conservative that on most of our creek banks, where the banks are very steep, we will never get to those more sensitive techniques. So we have some question as to whether there might be some other techniques that could be used but are not being proposed, because of the very conservative approach to the conditions under which they are willing to use those techniques. Commissioner Schink: Virginia, in the letter you reproduced for us, one of the underlined sections refers to low flow channels. I am wondering if her comments are applicable to these circumstances, which appear to be higher flow situations. Also, the second part of my question is, has anyone been up to Foothill Park to look at how the gabions look up there where the city did it, and has it been successful or unsuccessful? Ms. Warheit: About the flow, I will defer that question to Mitchell Swanson. I have seen the gabions at Foothill Park, and they are just wire baskets full of weeds. Those wire baskets not only have wire on the sides, but they have wire on the top. All you have to do is to look at that wire and imagine a snake trying to go across it, which is impossible, or birds or small animals walking on it, or if there is ever water, fish trying to move around through eddies where the wall is this wire mesh. When you see it at Foothill Park, you think that this does not look like the sort of thing that should be in a natural environment. Mitchell Swanson: Could you repeat the question regarding flow, please? Commissioner Schink: In the letter that was just handed out to us, on Page 2, the underlined section refers to the gabions, and it says they are not very conducive to fish life in a low flow channel. Are they really saying in that section that gabions are all that bad? Mr. Swanson: I have not seen the specific letter, but some of my experience with criticism of gabions by fish biologists is that the fish will go in and have a hard time getting out. Fish and fowl do not prefer gabions. Commissioner Schink: What I am trying to ask is, if you look at the detail in the way they are using the gabions in some of these low flow circumstances, I am not sure if it is the right comparison. ZB ! PCMin41Min 11-20.drf Page t 4 12-02-96 Ms. Warheit: Ms. Roper was responding to a site on San Francisquito Creek, so it is very similar. Commissioner Schink: They are talking about using gabions on the banks here, and it seems like the reference is to gabions on the creek bottoms. Mr. Swanson: Virginia is indicating that the gabions referred to in the letter were on the banks, as well. I think they can be used on the bed and the banks, but definitely on the toe of the banks, they would be in a low flow state. Commissioner Ojakian: I want Mr. Swanson to comment a little on some of the things he has just heard from our representatives of the Santa Clara Valley Water District. Maybe you do not need to comment on the gabion netting, because Virginia has done a good job of that, but if you want to add something there, great. The use of rock riprap and some of the erosion control techniques they are talking about you could cover, although you have done a great job in your letter of going into a lot of detail. I would just like to hear your comments to have that on the record. Mr. Swanson: My basic recommendation tends to reflect my response to this. To be fair in two lights, one is that with a project of this scale, it is difficult to see, foot by foot what is happening, although there are some important things going on in the creek from a habitat perspective, foot by foot. In light of that difficulty, that is why the first mitigation measure proposed was to join with the district in developing a detailed construction plan. The second recommendation was to conduct further research into alternative techniques, and this gets to gabions versus riprap, etc. I liken this to going to Chicago for pizza where there are about 100 different pizza restaurants and each has a special family pizza. They do their own pizza in a certain way -o deep dish, thin crust, the whole nine yards, but the bottom line is that everybody makes great pizza in Chicago. So there are many ways to do things, including bank treatments. I think we have a chicken and egg problem in this area. Districts, and the Corps of Engineers and everybody who does bank protection have tried and true methods that have been used for a number of years. Some of those have had a lot of conflict with biological requirements. Now we are seeing many new techniques coming in, but somebody has to try them. There is a major effort in the Sacramento River bank protection project in the central valley, an enormous project on the Sacramento River and major tributaries, to put in encapsulated soils as part of the structure, and to rely on toe protection rather than full bank revetments, and try to generate a meaningful riparian habitat in the current state of those rivers, both aquatic and riparian. Now there is a regulatory hook on salmon, so you have guys coming out from the waterways experiment station and running all over the country looking at the various techniques that have been done in trout streams and in places far away from people and things where flood control has been a big focus, but they have tried it somewhere, so there is an effort afoot, and it is changing all the time to the types of techniques that can be used to achieve flood control objectives and allow habitat. ZB I PCMin41Min i 1-20.drf Page 15 12-02-96 One of the more interesting things (and there is more common ground here than people realize) is that you consider stream corridor width and your options, and when people living along the creek demand a high level of flood protection, not having enough width is a bad situation for the creek habitat, as well as for Randy and Scott to deal with, because it just limits the options so much. That is the ultimate issue. There is an opportunity here (and I would rather look at this as an opportunity than as a problem) to have live structures that are on steeper than two-to-one slopes. It perhaps involves a little more expense. Maybe it is worth it under certain circumstances. There are techniques where people have used encapsulated soils with geo-webbing, for instance. You do not have an attack by water, but you have a slope stability issue there. You could have a mass landslide of the bank, which is typically what happens in these circumstances. That is the reason why I think we need to join with the district, and they are in this program EIR for erosion control right nov,, where they are going through all of these methods. That is a fluid situation that is lagging behind this document, to look into those applications to see if there is something that better meets the mutual needs of the City of Palo Alto and the District. The third point I made is about this geomorphic analysis. This is more or less up and coming in terms of applications of flood control problems and waterway management. A number of years ago, in the early 1950s, Dr. Luna Leopold, the son of Aldo Leopold, the famous conservationist, started quantifying stream data. The government was out measuring all of this water flow with stream gauges for water supply reasons, and he said, what does this look like in terms of the size and shape of the channel, relative to the flow. He found that there were relationships between flow and sediment and the size and shape of channels and their patterns in different climates. You see this repeated pattern in the nature of meandering streams. He quantified that, and that became the science of fluvial geomorphology. Now, 45 years later, that has moved more into the mainstream of looking at flood control. Fifty people at the district have taken short courses in fluvial geomorphology. The application here is that there may be circumstances where, in the city’s interest, we could avoid interventions by recognizing that it may already be stable. We can apply the principle that if the channel has already reached a certain width and there is not a bar or something pushing it laterally to erode, it may have essentially reached some sort of stability in its current state. Therefore, it may not need treatment. This is an avoidance concept. On the other hand, why put structures where you might not need them, such as the inside points of bars. etc. It is not that the district is proposing this, but you can be much more selective about what you are trying to do. Perhaps most importantly, Scott did show an example of installing toe protection. They showed it for the one-and-a-half year flood level. Typically, if you protect the toe of the bank up to about a one- or two-year flood elevation, that will go most of the way to protect that bank. It also brings soil closer to water, making it easier to get plants started. Soil binding by plant roots and woody vegetation is a key component in bank stability, and of course, in habitat. I think that is one of the most challenging situations that we have here. We have a deep, narrow, incised channel with big trees on top of the bank that are very difficult to get ZB I PCMin41Min I 1-20.drf Page 16 12-02-96 reestablished without irrigation and constant maintenance. It takes forever to grow a large enough tree to shade the creek. So what I saw was that there may be opportunities to avoid certain actions in certain places. There certainly are opportunities to look at new techniques, new technologies, and bring new information to bear, which is going to change in the next six months. We may know new things then. It has changed over the last six months. The City would stay along with the project as the?’ develop the one- to 20-inch construction plans. We are at a scale of one to one hundred inches nov,;, looking at the EIR. The district, of course, is in the process of doing their program EIR for erosion control and maintenance. Gabions have been used extensively by the District. There are places where they have been pretty successful in getting vegetation of some sort to grow in them, but in this climate, gabions are difficult, because they have low soil retention. They are rocks, and do not have a lot of water holding capability. You will see pictures of these things used in Italy and in the eastern part of the United States where it rains during the growing season. You would see things growing fairly prolifically, but out here, the tendency is that they attract more dr?,; species and more invasive types of species. They are not typical of a good riparian community. So a lot of places have shied away from those techniques. Gabions could be used as toe protection, creating some soil at that mid-level of the couple of years flood level. You could have a planting surface that could be used in that regard. But that is not always preferable. Riprap rock can do the same thing. My final po.int is about the channel maintenance program in terms of review, reflecting the city’s policies. Again, this is in a state of change because of the program EIR that is under way. About eight years ago, I traveled over to the United Kingdom and Bavaria, places where they have instituted fairly progressive and very different waterway management programs. One of the things I was amazed to see was that in Bavaria, landscape architects were designing flood control projects in the cities, and the biologists were designing stream maintenance plans in the countryside. We visited them, and they came here, as well. I brought them down to the Santa Barbara County Flood Control Agency. The biologist there explained how he used an avoidance approach. This struck me as a subtle but very important difference. He was also trained in flood control techniques and hydrology, thebasics about flood control and what they are trying to accomplish, but he had an eye for the structure of the stream and the habitat, how things were laid out. what was important and how to make those decisions about what plants had to be taken out to maintain flow capacity. It was really interesting. He basically built a map that he carried through time. Through each project, he could track the ecological health, along with the flood control maintenance plan. It struck me as a very interesting approach. Perhaps that is what we are doing here with the city’s policies toward habitat and trees, etc. That sort of integrated approach might be useful here, bein.g mindful of the flood control objectives. When the city engaged my services, Virginia asked if there were alternatives to what we see here. There are a lot of pizzas in the world. There are a lot of different ways of doing things to accomplish the same thing. Are there other ways to plan what we do in the creek? Just as important as what we are putting in is how is it going to be managed in the long term. Yes, there ZB { PCMin41Min 11-20.drf Page 17 12-02-96 are very different ways of looking at that, so again, I emphasize the opportunity aspect of this, rather than the problem aspect, realizing there are many ways to make a pizza. I would now like to show you some examples of some alternative treatments. These are a few examples of encapsulated soils. This is a nice little creek in New Jersey. It actually had suffered from intense pollution from toxic metals. They had to remove the substrate under and around the creek and reconstruct it. Not unlike what the district is proposing, they put a bed of cobbly material or riprap on the bed to give it vertical stability. They then took coir fabric, a woven coconut fabric that is biodegradable roughly in five years. They encapsulated soil inside of it and compacted it. They are staked in the ground and folded over, with plant material placed inside the seams of these. Commissioner Qiakian: From a cost standpoint, is there any difference in using that particular technique versus using the gabion technique? Mr. Swanson: These are probably more labor-intensive, therefore, a bit more costly. It depends upon how critical the hydraulics and the site conditions are and what tensile strength you need in the fabric. The Sacramento River Flood Control Agency dealt with this, and they developed a conservation corps for the American River Parkway of under-employed and disadvantaged folks to actually go out and do these kinds of projects. They have a roving corps to pick up trash, install these things, etc., and they realize a substantial labor savings. If a conventional construction company were doing this, you are looking at something that could cost a bit more, but not necessarily. It depends. There are different ways to cook pizzas. This shows the same stream a couple of growing seasons later. We have willow in the foreground, and the fabric gives time for the plants to get going. Once the plants get going, the fabric degrades and you have a root-bound structure in the bank. which is your bank protection. I don’t know if any of you have spent time on the rivers north of here -- the Russian, the Eel -- but there are places where you literally have one-to-one slope banks on the sides of rivers that are a solid willow mat. They handle 100,000 cfs, an incredible force, and they take it. But it takes something to get that established. It is hard to put soil on a one-to-one slope and have plants thrown in and take hold, so the fabric buys you some time, and you hope you are not faced with a severe event in the meantime. You do need a period of time for this to set. With toe protection and what we are faced with here, these could work quite well and take punishment. This is another stream in the midwest. Hei-e they have a climatic benefit of rain during the year. They put in some toe protection here and some encapsulated soil. They have a layer of fabric with soil underneath, and willows and live plantings put in. They will put another layer over the top so that these things will be wedged in like a sandwich. They will grow quite prolifically. This is a larger river is South Dakota where they are relining a whole river. They are using some rock toe protection and spreading it out, creating a new flood plane. We have incised channels ZB I PCMin41Min I 1-20.drf Page 18 12-02-96 here. The concept is that most of the hydraulic force will be expended and will spread out onto the flood plane. They are working with the geomorphology of the stream. This is a very interesting installation in New Jersey on the Raritan River. The soil is being compacted and the fabric will be folded over the top. The plants will be in between. There were very high environmental restrictions on this site -- no loss of vegetation, no encroachment into the channel, etc. It was not cheap, but it seems to work pretty well to give the plants enough time to get growing, and in five years, this fabric will decay and go away. There will just be roots holding this, with a rock toe. This is the Upper Truckee River at South Lake Tahoe, which has been straightened and channetized. A lot of things happened around here when development occurred. This was once a very nice, meandering meadow stream that has been straightened and subsequently incised. You can see extensive erosion on the banks. Large trees are bending and falling in downstream. The problem here is that the stream used to be within a few feet of that meadow, and it spread out. With the straightening, it has gone downstream, and the hydraulic forces are much more concentrated. V~rhat the stream does is to t~’ and work out of that and reestablish its meandering after being straightened. (More slides were showan and described.) That completes my presentation. Chairperson Cassel: Are there any questions? Commissioner Byrd: That was a terrific presentation, one of the most informative and interesting I have seen since I have been on the commission. I would ask that you consider giving this same briefing to our newly elected member of the board of directors of the Water District, Greg Zlotnik in District 5 who will be acting for all of us who live in this part of the county. I think this would be instructive for Greg, and from what I know of him, I believe he would welcome this presentation. Commissioner Ojakian: I want to second what Owenjust said. I am sorry I did not bring my children down here to see it. Chairperson Cassel: We have a card from one member of the public who wishes to speak. Douglas Graham. 984 Ilima Way,.Palo Alto: I also appreciate the privilege of attending this seminar in fluvial geomorphology. It was most interesting. I am a member of the Santa Clara Vatlev Water District’s Flood Control Advisory Committee for the Northwest Flood Control Zone. in which Palo Alto is located. ZB I PCMin41Min 11-20.drf Page t 9 12-02-96 I am somewhat familiar with the Adobe Creek Project from the earlier phases from the flood basin on up to E1 Camino. I have also been able to participate in the water district’s tours for the advisor5.’ committees for about the last ten years, looking mainlv at some of the upper parts of this project, like at Edith Avenue near Foothill Expressway in Los Altos. I only have one comment to make. That is that if we can do an.vthing at E1 Camino to save the trees above and below, I believe that will be very important not only for our city aesthetics, but also for the creek habitat. I got a very unclear picture, both from the reading and from the discussion tonight, as to exactly what trees will remain and what ones will have to go. I would hope that this entire issue can be reviewed thoroughly between the staffs. I have the highest respect for both staffs and for their diligence in protecting the environment as well as protecting the structures of our city, from flooding. I am sure that this can be worked out to everyone’s satisfaction. 2 I do have one more comment on the gabions. Years ago, I was excited about the idea of gabions. We saw some nice pictures of gabions going in in the south county., but the gabions at Foothill Park and the gabions we have installed as part of the Matadero Five project in my neighborhood, right above my house, I am not so impressed by. One of the disappointments to me is that when they make gabions, they do not go and get natural, stream-rounded rocks out of some stream where they are perhaps not needed as much and put them into these cages. Instead, they go to a quarry and blast limestone into nice sharp, jagged pieces, absolutely fresh, unweathered, and what you get is a highly reflective surface. So these gabions do not end up looking much better than new concrete walls. So if we are going to have gabions there at Adobe Creek and E1 Camino. I would hope we could do something from an aesthetic standpoint of having colored rock or something to minimize the glare from the sunlight that is going to be reflected off of this fresh limestone or whatever it will be. : For us, at the big confluence structure where the Barron Creek bypass joins the intake from Matadero Creek to further bypass around the Barron Park neighborhood as part of this new flood control project, at that confluence structure, they followed the wishes of the neighborhood and incorporated coloring into the concrete walls. It makes a big difference. I would urge Planning Commission members who have perhaps not seen that confluence structure to go and look at it. It is not beautiful, but it is one heck of a lot better when you have colored concrete that was carefullv matched to our adobe soil than it is when you have the fresh, unweathered limestone look. So there are things that can be done, both from the aesthetic and biological standpoints, and I urge both sides (I shouldn’t say "both sides", as we are all on the same side) both agencies to continue to work together in the cooperative way in which they have. Thank you. Chairperson Cassel: Let me review our purpose tonight. We need to have staff comments, and then recommend to the CiD’ Council comments on the Draft Environmental Impact Report for the Adobe Creek Watershed Planning Study, Santa Clara Valley Water District. We have the option of supporting the staff commets and recommending that. We have the option of making additional comments, or of course, not supporting it. ZB ] PCMin4 [ Min 11-20.drf Page 20 12-02-96 Commissioner Ojakian: In reading Mr. Swanson’s letter on this matter, he speaks about how our Comprehensive Plan talks to the notion of avoidance as opposed to mitigation. So we have a Comprehensive Plan with a certain emphasis, and we have an EIR that is really looking more into the mitigation aspects of this. When you have our document, in essence, in conflict with the EIR, what position does the city typically take? Or is it grounds for challenging the EIR? Ms. Cauble: My view is that as in the case of any EIR, part of required analysis is the conformance of the project in question to applicable, major planning and policy documents. A general plan obviously is at the top of that hierarchy. The district, because their project traverses several different jurisdictions, has made an attempt in this document to do some analysis of the major planning policies and ordinances in the respective jurisdictions. If the commission has any additional comments to make beyond those recommended by staff as to whether the analysis is correct as to conformance or lack of conformance, that is absolutely appropriate commentary. Ultimately, what that issue relates to is a judgment as to whether the project has significant impacts, and if so, whether or not they are mitigated. So it is hard, in the abstract, to say that if we think it doesn’t conform to our Comprehensive Plan, and they think it does, can we legally challenge it? It only needs to bail down to whether or not they meet the CEQA standard for identifying significant impacts. So at this point, the key thing is for the city to exercise its opportunity to comment on that issue, and give the district an opportunity to respond to our analysis of how this project relates to our important planning documents. Commissioner Ojakian: I am not suggesting that we do challenge it at this stage. It is important that we make our comments, but I also think that in reading Mr. Swanson’s analysis and the staff report, that he and the staff make some extremely valuable points that we need to have taken into consideration when this project does occur. So I just want to make sure that that is in the record. MOTION: Commissioner Schink: I would move the staff recommendation, which is essentially the staff comments and Mr. Swanson’s letter. SECOND: By Commissioner Ojakian. Commissioner Schink: Mr. Swanson made a very. impressive presentation. I would just say that if you have an opportunity to present the same information to the City Council, I would encourage you to lead off with Mr. Swanson’s presentation. That might save all of them from wandering down the same road that some of us wandered dov,~n for a long time today. It was most persuasive, so I think that is the best place to start. A ve~, good job. Commissioner Ojakian: First of all, I think the water district’s goals are lofty goals in terms of trying to prevent flooding and reduce potential negative economic impacts, and ensure water quality and protect water supply. I don’t think anyone would challenge those particular goals, but our responsibility as Planning Commissioners of the City of Palo Alto is to be concerned about how you actualize those goals. In particular, I would hope that you can achieve those ZB ] PCMin4 ] Min 11-20.drf Page 21 12-02-96 goals without affecting certain things. Those include the riparian habitat, and getting back to a comment that Commissioner Schmidt made earlier, also any impact on the businesses that we have along Et Camino Real. I heard what you said, but I also know what happened in the last project there. Several businesses were highly impacted, and we had a very concerned Chamber of Commerce from that. We had a couple of businesses, in fact, suggest that they went out of business because of some of the activity that was going on. I would hope that you would perform techniques that would not further erode the creek or have an effect on the tree life. I would encourage you to use methods that are more oriented towards avoidance, as Mr. Swanson pointed out. and emphasize creek protection, not to simply take a civil engineering approach or solution to this particular project, but to look at it in a much more site-specific way. I am reiterating some of the things that have already been said, but from a Palo Alto perspective, even though from yours, this might be a small portion of the creek that is affected, we. as a Planning Commission and as a City Council and even with our CPAC group, which previously looked at our assets in the City. of Palo Alto, and one of the assets we cherish is our creeks. We are appreciative of the fact that, in fact, they were not all channelized and concreted over. Those that we have we would like to save. Those are my comments. Commissioner Byrd: Virginia’s letter is unambiguous in its statement that gabion baskets have a significant environmental impact and reduce the habitat value, and should be avoided whenever possible. If the motion is to forward these comments to council, I would like to add to that thought, which is, concrete sacking is also a method of erosion control that at this point, we should be moving past. We have heard about a lot of other alternatives, and I am concerned, from a biological and aesthetic standpoint, that we not add additional concrete sacking to the natural portions of our remaining creeks. So I would like to ask that we add a concern about concrete sacking, in addition to gabion baskets, that we forward to council. Commissioner Schink: As maker of the motion, I would be happy to accept your comments along those lines. Commissioner Ojakian: As seconder, I would approve of that addition. Commissioner Schmidt: I have another question of the district as to whether they have used any of these methods that Mr. Swanson outlined and showed us photographs. Mr. Tallev: We continue to try new methods whenever they come up. What we are trying to do is to incorporate those into our maintenance program, and find out where they are feasible and where they work best. We will continue to do that. Commissioner Eakins: I agree with my colleagues that we should not use any more concrete or any more jagged rock or any more metal mesh anywhere. It is not just habitat we are trying to save. We are trying to save the world for human beings. The planet will go on, but it will not be ZB I PCMin4 t Min 11-20.drf Page 22 12-02-96 habitable by any of us, so whatever we can do, and Palo Alto is fairly good at demonstrating leadership in these areas. We now have a ten-week-old program featured on the front page of the Palo Alto Weekly about using poor, mostly unemployed people to do simple labor. Our city manager is taking the lead on doing this. Wouldn’t that be wonderful to see them with those little machines that we saw tonight in the slides, and the coconut fiber, making something really great out of this opportunity to control erosion at certain vulnerable points. There is a lot of dissatisfaction with the channelized creeks, especially as they go through our parks. So I am adding on something else. It is not where you have the big maintenance problems, but those channelized creeks are just - I won’t even quote Peter Calthorpe, our CPAC consultant, because his language became obscene when he referred to the channelized creeks. We would like to have your cooperation for opening them up in the parks where flooding is around playground equipment and picnic tables, not in people’s living rooms, where they can be tolerated and understood. So I am preaching, but I am inspired that the creeks can be more of a resource and everyone can come off feeling a lot better. Chairperson Cassel: I will support the motion, but I want to emphasize how difficult I think this task is. We are going backwards from a situation that we started many years ago when we did not allow ourselves enough space. It is my understanding that our water table has dropped. I am sure that is aggravating this stream and other streams by making this channel deeper. We live in a semi-arid area that we want to pretend is not. Everything that is green is irrigated. It is very noticeable if you come in from another area. The streams in New Jersey are fed by continuous rains, about four inches a month, every month of the year. It gets a little lighter in the summer, a little heavier in the spring, but the nature of streams is different. They are flatter. The same thing for Illinois. I lived through a flood in Illinois, and it is really interesting when you live on fiat land and it is flooded. But this is not fiat land. It is steep, and it creates specific kinds of problems. I think we really aggravate it every time we straighten the creek and every time we move a channel, every time we don’t look for a place to get a flood plane, every time we don’t look for a building that is overhanging the edge of the bank and try to get rid of it instead of supporting it. I know from previous experience and comments we have had that the cemetery people are not the easiest people to work with. But it is their people underground that they are trying to protect, and they may have to do something about that in cooperation, in this case. It may be easier to prevent more problems for them, if they move a building and make a more gentle slope. So I would encourage more negotiation, more small areas where you can hold water back and let the flow go off at a slower pace. It does not seem to be something that we think about very much around here, but in New Jersey, they do, in fact, make restrictions. You cannot have more water flow off your property after you finish your construction than before you began the construction. So if you want to put up a large building with a big parking lot, you better figure out how you are going to keep that water on site for the length of time it would have taken the water to move off the site before the construction. We do not seem to use those ideas, but I would like to encourage us to look for other creative ways to keep the flow going into the streams a little slower, and thus, we would not need quite the capacity. ZB] PCMin4 ] Min 11-20.drf Page 23 12-02-96 Commissioner Eakins: Another thing I wanted to ask about is whether there is any way to work with all jurisdictions about controlling the amount of storm water that goes into these drains, having more water retained on sites, as a general policy? Can you do anything about that? Mr. Tallev: It is our practice that when we comment to the city on these kinds of development issues, we always say exactly what Chairperson Cassel just said. That is, address the impact of the additional runoff. MOTION PASSES: Chairperson Cassel: Is there any further discussion on this motion? The motion is to support the staff recommendation and to add to it the letter from Virginia Warheit and to forward our comments on to the Cit37 Council, where they will be forwarded on to the Santa Clara Valley Water District, and to include the thought th~it concrete sacking is as inappropriate a measure of erosion control as are the gabion baskets. All those in favor, say aye. All opposed? That passes unanimously on a vote of 6-0, with Commissioner Beecham absent. I want to thank the representatives from the Santa Clara Valley Water District for coming and sharing with us. This will go to the City Council on December 16. ZB [ PCMin41Min 11-20.drf Page 24 12-02-96