Loading...
HomeMy WebLinkAbout2001-08-06 City Council (8)City of Palo Alto City Manager’s Report TO:HONORABLE CITY COUNCIL FROM:CITY MANAGER DEPARTMENT: PUBLIC WORKS DATE:AUGUST 6, 2001 CMR: 334:01 SUBJECT:NEW LAND DEVELOPMENT REVIEW PERMIT PROVISIONS PROPOSED AS PART OF NATIONAL POLLUTANT DISCHARGE ELIM~ATION SYSTEM STORM WATER DISCHARGE PERMIT RENEWAL This is an informational report and no Council action is required. National quality r~ .issued a Control BACKGROUND The San rancisco Bay Regional Water Quality Control Board (Regional Board) issues )ollutant Discharge Elimination System (NPDES) permits that stipulate water tuirements for discharges to waters of the State. In 1990, the Regional Board ioint NPDES permit to the Santa Clara Valley Nonpoint Source Pollution rogram (Program), consisting of 13 Santa Clara Valley cities, the County of Santa C~ :a, and the Santa Clara Valley Water District (co-permittees), for discharge of storm w :er to local creeks and the Bay. The permit required the development and impleme ~.ation of an Urban Runoff Management Plan containing control measures to be impleme :.ed by municipalities, residents, and businesses to reduce storm water pollution. The Plan dentified best management practices, public outreach and education programs, and loca nspection and enforcement activities designed to improve storm water quality. The Regional Board’s regulation of storm water discharges has been based upon the development and implementation of best management practices (BMPs), as contrasted to the more traditional approach of specifying numerical discharge standards. The Program entities have worked to continuously improve their Urban Runoff Management Plans over the years to control pollution "to the maximum extent practicable," based upon improvements in available technology, improved identification and understanding of critical pollutants, and practical experience withvarious BMPs. The Regional Board issues a new NPDES permit every five years, each time redefining what is required to satisfy the standard of controlling storm water pollution "to the maximum extent practicable." A second-generation NPDES permit was issued to the Program in 1995. The new permit required the co-permittees to adopt a series of performance standards, which specify the BMPs and the level of effort that will be implemented for each of the elements covered by the co-permittees’ Urban Runoff Management Plans (e.g. CMR:334:01 Page 1 of 4 industrial/commercial facility inspection program, street maintenance, etc.). In 1997, the Program was renamed the Santa Clara Valley Urban Runoff Pollution Prevention ~ Program to better represent its adopted mission and eliminate the public’s confusion over the term "nonpoint source pollution." The Program’s third-generation NPDES permit was up for Regional Board consideration in 2001. DISCUSSION In February 2001, the Regional Board issued a new NPDES permit to the Program, covering most of the elements of the Program’s Urban Runoff Management Plan. The permit provisions covering land development review procedures, .however, were not adopted at that time due to the controversial nature of the proposed provisions. The latest draft of the land development provisions are attached for reference (Attachment A). It was mutually agreed by the Regional Board staff and the co-permittees that more time was needed to allow the parties to work together to craft modified permit language that would be acceptable to both parties as well as the land development and environmental communities. The proposed land development permit provisions would have a significant impact on the City’s land development review process. The provisions would also increase the cost to develop in the Santa Clara Valley relative to other regions of the Bay Area, thereby potentially discouraging future development and redevelopment in Palo Mto and surrounding communities. A summary of the new permit provisions is cot rained in Attachment B. The new permit would require developers to treat a certain percentage of the storm water runoff from newly developed or redeveloped sites by directing ae runoff through a vegetated swale, detention basin, or a structural filtration device. Ir~ tially the requirements would apply to projects of one acre or greater, but in later ye~:rs would apply to projects as small as 5000 square feet (the intent is to regulate projects ~:hat make up 80% of the newly created impervious area). There are also requirements for municipalities to verify the maintenance, of privately-installed pollution control ~neasures. Although staff agrees with the underlying intent of the permit provisions and has been a leader in the Bay Area in requiring innovative storm water controls for land development projects, staff cannot support the proposed permit provisions because they are unclear and onerous in nature. The land development review permit provisions were the subject of a Regional Board workshop and public hearing at the July 18, 2001 Board meeting. Representatives from several of the co-permittees testified at the hearing in opposition to the adoption of the current permit language and described their primary objections. The Regional Board was receptive to the co-permittees comments and voted to postpone adoption of the permit until October, once again providing more time for the Regional Board staff and the co- permittees to reach consensus. Staff will take an active role in the permit negotiations and is cautiously optimistic that the parties can agree on a proposal that will achieve the underlying water quality protection goals while mitigating the resource impacts to municipalities and developers. CMR:334:01 Page 2 of 4 RESOURCE IMPACT It is unclear at this time the amount of increased resources that would be required to implement the proposed permit provisions. Additional staff resources could be required in the Planning, Engineering, and/or Building Inspection Divisions. Adoption of these new permit requirements could exacerbate the current shortage of funding for storm drainage functions within the City. Staff will need to explore the feasibility of implementing increased land development user fees or a Citywide NPDES fee to cover the costs of land development drainage and grading review and other storm water quality protection activities. POLICY IMPLICATIONS The underlying goals of the proposed permit language are consistent with a number of policies and programs contained in the Comprehensive Plan: Policy N- 18: Reduce non-point source pollution in urban runoff from residential, commercial, industrial, municipal, and transportation land uses. Program N-23: Work with regulatory agencies, environmental groups, affected businesses, and other stakeholders to identify economically viable Best Management Practices (BMP) for reducing pollution. Policy N-19: Limit the amount of impervious surface in new development or public improvement projects to reduce urban runoff into storm drains, creeks, and San Francisco Bay. Program N-69: Establish a standardized process for evaluating the impacts of development on the storm drainage system. Require mitigation for increases of storm runoff into this system. Staff will work with the Regional Board and the co-permittees to develop alternative permit language that facilitates these goals without unduly burdening municipalities and developers. ATTACHMENTS Attachment A: Draft Regional Board Tentative Order Attachment B: Summary of proposed permit provisions PREPARED BY: JOE TERESI Senior Engineer CMR:334:01 Page 3 of 4 DEPARTMENT HEAD: CITY MANAGER APPROVAL: G OBERTS"-~ 1"Director of Public Works Assistant City Manager CMR:334:01 Page 4 of 4 ATTACHMENT A CALIFORNIA REGIONAL WATER QUALITY CONTROL BOARD SAN FRANCISCO BAY REGION TENTATIVE ORDER NPDES PERMIT NO. CAS0297!8 AMENDMENT REVISING PROVISIONS C.3 AND C.14 OF ORDER NO. 01-024 FOR: SANTA CLARA VALLEY WATER DISTRICT, COUNTY OF SANTA CLARA, CITY OF CAMPBELL, CITY OF CUPERTINO, CITY OF LOS ALTOS, TOWN OF LOS ALTOS HILLS, TOWN OF LOS GATOS, CITY OF MILPITAS, CITY OF MONTE SERENO, CITY OF MOUNTAIN VIEW, CITY OF PALO ALTO, CITY OF SAN JOSE, CITY OF SANTA CLARA, CITY OF SARATOGA, AND CITY OF SUNNYVALE, which have joined together to form the SANTA CLARA VALLEY URBAN RUNOFF POLLUTION PREVENTION PROGRAM The California Regional Water Quality Control Board, San Francisco Bay Region, hereinafter referred to as the Regional Board, finds that: Existing Permit and Amendment of Provisions C.3 and C.14 1. The Regional BOard adopted Order 01-024 reissuing waste discharge requirements under the National Pollutant Discharge Elimination System (NPDES) for the Santa Clara Valley Urban RunoffPollution Prevention Program for the discharge of stormwater to the South San Francisco Bay and its Tributaries. As outlined in Finding 17 of Order 01-024, Provision C.3 of Order 01-024 is to be revised in response to the "Cities of Bellflower, et. al." decision by the State Water Resources Control Board (State Board Order No. 2000-11). Provision C.14 is hereby revised to extend the permit expiration date by approximately three months, as agreed to by the Dischargers, in order to allow adequate time for implementation of the revised Provision C.3. o Order 01-024 recognizes the Santa Clara Valley Urban Runoff Management Plan (Management Plan) as the Dischargers’ Comprehensive Control Program and requires implementation of the Management Plan, which describes a framework for management of stormwater discharges. The 1997 Management Plan describes the Program’s goals and objectives and contains Performance Standards, which represent the baseline level of effort required of each of the Dischargers. The Management Plan contains Performance Standards for seven different stormwater management activities. The Performance Standard and Supporting Documents for Planning Procedures for new development are contained in Attachment 1. Nature of Discharges and Sources of Pollutants 4. Urban Development Increases Pollutant Load, Volume, and Velocity of Runoff: During urban development two important changes occur. First, natural vegetated pervious ground cover is converted to impervious surfaces such as paved highways, streets, rooftops, and parking lots. Natural vegetated soil can both absorb rainwater and remove pollutants 2 providing a very effective natural purification process. Because pavement and concrete can neither absorb water nor remove pollutants, the natural purification characteristics of the land are lost. Secondly, urban development creates new pollution sources as human population density increases and brings with it proportionately higher levels of car emissions, car maintenance wastes, municipal sewage, pesticides, household hazardous wastes, pet wastes, trash, etc., which can be washed into the municipal separate storm sewer system (MS4). As a result of these two changes, the runoffleaving the developed urban area is significantly greater in volume, velocity and pollutant load than the pre-development runoff from the same area. Certain pollutants present in storm water and/or urban runoff may be derived from extraneous sources that Dischargers have limited or no direct jurisdiction over. Examples of such pollutants and their respective sources are: PAHs which are products of internal combustion engine operation and other sources; heavy metals, such as copper from brake pad wear and zinc fi’om tire wear; dioxins as products of combustion; mercury resulting from atmospheric deposition; and natural-occurring minerals from local geology. However, Dischargers can implement control measures, .or require developers to implement control measures, to reduce entry of these pollutants into storm water and their discharge to receiving waters. o These pollutants can have damaging effects on both human health and aquatic ecosystems. In addition, the increased flows and volumes of stormwater discharged from new impervious surfaces resulting from new and redevelopment can significantly impact beneficial uses of aquatic ecosystems due to physical modifications of watercourses, such as bank erosion and widening of channels. Water Quality Degradation Increases with Percent Imperviousness: The increased volume and velocity of runoff from developed urban areas greatly accelerates the erosion of downstream natural channels. Numerous studies have demonstrated a direct correlation between the degree of imperviousness of an area and the degradation of its receiving water quality. Significant declines in the biological integrity and physical habitat of streams and other receivingwaters have been found to occur with as little as a 10% conversion from natural to impervious surfaces. (Developments of medium density single family homes range between 25 to 60% impervious). Implementation 8. The revised Provision C.3 is intended to enhance the Dischargers’ existing Performance Standard for new development, through addition of provisions to more effectively incorporate source control measures, site design principles, and structural stormwater tr.eatment controls in new development and redevelopment projects in order to reduce water quality impacts of stormwater runoff for the life of these projects. The consistent application of such measures is intended to greatly reduce the adverse impacts of new and redevelopment on water quality and beneficial uses by reducing stormwater pollutant impacts and increases in peak runoffrate and duration, which can affect the stability ofwaterbodies, both up and downstream of projects. 3 Because land use planning is where urban development begins, it is the phase in which the greatest and most cost-effective oppommities to protect water quality in new and redevelopment exist. When a Discharger incorporates policies and principles designed to safeguard water resources into the General Plan and development project approval processes, it has taken a far-reaching step towards the preservation of local water resources for future generations. 10.The revised Provision C.3 is written with the assumption that Dischargers are responsible for considering potential stormwater impacts when making planning and land use decisions. Neither Provision C.3 nor any of its requirements are intended to restrict or control local land use decision-making authority. Public Process 11. The action to modify an NPDES Permit is exempt from the provisions of Chapter 3 (commencing with Section 21100) of Division 13 of the Public Resources Code [California Environmental Quality Act (CEQA)] pursuant to Section 13389 of the California Water Code. 12.The Dischargers and interested agencies and persons have been notified of the Board’s intent to modify waste discharge requirements for the existing discharge and have been provided opportunities for public meetings and the opportunity to submit their written views and recommendations. 13.The Regional Board has conducted public meetings to discuss the draft revised Provisions C.3 and C.14. 14.The Board, in a public meeting, heard and considered all comments pertaining to the draft revision of Provisions C.3 and C. 14. IT IS HEREBY ORDERED that the Dischargers, in order to meet the provisions contained in Division 7 of the California Water Code and regulations adopted hereunder and the provisions of the Clean Water Act as amended and regulations and guidelines adopted hereunder, shall comply with the following: Provision C.3. New and Redevelopment Performance Standard Enhancement of Order No. 01-024 is hereby revised to read as follows: The Management Plan contains performance standards and supporting documents to address the post-construction and construction phase impacts of new and redevelopment projects on stormwater quality (Planning Procedures and Construction Inspection Performance Standards). The Dischargers shall continue to implement these performance standards and continuously improve them to the maximum extent practicable in accordance with the following sections. 4 aa Performance Standard Implementation: The Dischargers shall continue to implement and continually improve the following performance standards for planning procedures: Each Discharger shall have adequate legal authority to implement new development control measures as part of its development plan review and approval procedures; ii.Each Discharger shall provide developers with information and guidance materials on site design guidelines, building permit requirements, and BMPs for stormwater pollution prevention early in the application process, as appropriate for the type of project; ooo ln.Each Discharger shall require developers of projects that disturb a land area of five acres or more to demonstrate coverage under the State General Construction Activity Stormwater Permit; iv. vi. Each Discharger shall require developers of projects with potential for significant erosion and planned construction activity during the wet season (as defined by local ordinance) to prepare and implement an effective erosion and/or sediment control plan or similar document prior to the start of the wet season; Each Discharger shall ensure that municipal capital improvement projects include stormwater quality control measures during and after construction, as appropriate for each project, and that contractors comply with stormwater quality control requirements during construction and maintenance activities; and Each Discharger shall provide training at least annually to its planning, building, and public works staffs on planning procedures, policies, design guidelines, and BMPs for stormwater pollution prevention. bo Development Project Approval Process: Dischargers shall modify their project review processes as needed to incorporate the requirements of Provision C.3. Each Discharger shall include conditions of approval in permits for applicable projects to ensure that pollutant discharges and runoff flows are reduced to the maximum extent practicable The goal of the conditions of approval should be that pollutant discharges and changes in runoff flows where they can cause damage to downstream waterbodies, are reduced to the maximum extent practicable, and that contributions to exceedance of receiving water quality standards do not occur for the life of the project, through implementation of control measures to the maximum extent practicable. Such conditions shall, at a minimum, address the following goals: ii. Require project proponent to implement site design/landscape characteristics where feasible which maximize infiltration (where appropriate), provide retention, slow runoff, and minimize impervious land coverage, so that post-development pollutant loads from a site have been reduced to the maximum extent practicable; and For new and redevelopment projects that discharge directly to water bodies listed as impaired by a pollutant(s) pursuant to Clean Water Act Section 303(d), ensure that post-development runoff does not exceed pre-development levels for such pollutant(s), through implementation of the control measures addressed in this provision, to the maximum extent practicable, in conformance with Provision C. 1. New and Redevelopment Project Categories - Size of Projects Addressed by this Provision: New and redevelopment projects are grouped into two categories, based on project type and size. Stormwater runoff from Group 1 Projects is considered to have greater potential impacts on the beneficial uses of water bodies in the Santa Clara basiri; thus, Group 1 Projects are subject to all the requirements of this Provision upon implementation. Group 2 Projects, which at this time are considered to have lesser potential impacts on the beneficial uses of water bodies in the Santa Clara Basin, are exempt from the Numeric Sizing Criteria of Provision C.3.d, Operation and Maintenance requirements of C.3.e, and the Limitation on Increase of Peak Stormwater Runoff Discharge Rates of C.3.f. until July 15, 2003, at which time they will have the same status as Group 1. ii. Group 1 Projects: Group 1 Projects consist of all projects for which a development application has not been deemed complete as of the effective date of Provision C.3.b and which are in the following categories: Commercial, industrial, or residential developments that create o~ (43~ 560 ~0 or more of impervious surface, including roof area, streets and sidewalks. This category includes any development of any type on public or private land, which falls under the planning and building authority of the Dischargers, where one acre or more of impervious surface, collectively over the entire project site, will be created. Significant redevelopment projects. This category is defined as the creation or addition or structural replacement or significant reconstruction of at least one acre (43,560 square feet) of imperviouS surfaces on an already developed site, or significant redevelopment that encompasses one acre of impervious surface, including roof area. Significant redevelopment includes: the expansion of a building footprint and/or floor area, or addition to an existing structure; significant reconstruction of an existing structure; or replacement of a structure. Significant redevelopment also includes replacement of impervious surface that is not part of a routine maintenance activity. Redevelopment projects that, when complete, would result in reductions in site imperviousness by twenty percent (20%) or more from the existing site condition are excluded (exempted) from the category of Significant Redevelopment Projects. Streets, roads, highways, and.freeways that are under the Dischargers ’jurisdiction and that create one acre (43,560 square feet) or more of impervious surface. This category includes any paved surface used for the transportation of automobiles, mack.s, motorcycles, and other vehicles. Group 2 Projects: Group 2 Projects consist of all other (i.e., not in Group 1) new and significant redevelopment projects that create 5 00~Q_Qg_.~s0 square.feet or more of additional impervious surface. Group 2 Projects must be designed and operated to comply with all of Provision C.3 except the Numeric Sizing Criteria of Provision C.3.d, Operation and Maintenance requirements of C.3.e, and the Limitation on Increase of Peak Stormwater Runoff Discharge Rates of C.3.f. do 111 ¯Alternative Project Size Proposal: All Dischargers shall review the statistics and pattern of new development and significant redevelopment within their jurisdictions, for all Group 1 and 2 Projects, both in the recent past, and going forward. In the Annual Reports due September 15, 2002, each Discharger shall report a summary of these statistics (numbers, types, and sizes of new and redevelopment projects) showing the ranges of impervions surface creation. Using this information, each Discharger may propose, for approval by the Executive Officer, an alternative Group. 1 Project size, in amount of impervious surface addition, that would encompass approximately 80% of new impervious surface creation in a typical recent year. In the event that a Discharger makes no such proposal, the Group 2 Project definition shall be included in the Group 1 Project definition, making both Group 1 and 2 Projects subject to all the requirements of Provision C.3. Numeric Sizing Criteria: All Dischargers shall require that treatment Best Management Practices (BMPs) be implemented at all Group 1 and 2 development projects within their jurisdictions. To ensure their effectiveness, all treatment BMPs for a Group 1 project shall be sized to meet one of the following sizing criteria: ii. Volume Hydraulic Design Basis: Treatment BMPs whose primary mode of action depends on volume capacity, such as detention!retention units or infiltration structures, shall be designed to mitigate (infiltrate or treat) stormwater runoff from: each runoff event up to and including the 85th percentile 24-hour storm runoff event determined as the maximized capture storm water volume for the area, based on historical rainfall records, from the formula recommended in Urban Runoff Quality Management, WEF Manual of Practice No. 23/ ASCE Manual of Practice No. 87, (1998), or the volume of annual runoffbased on unit basin storage volume, to achieve 80 percent or more volume treatment by a method such as that recommended in Appendix D of the California Stormwater Best Management Practices Handbook, (1993). Flow Hydraulic Design Basis: Treatment BMPs whose primary mode of action depends on flow capacity, such as swales, sand filters, or wetlands, shall be sized to handle: ¯10% of the 50-year design flow rate, or ¯a flow that will result in treatment of the same portion ofrunoffas treated using volumetric standards above, or ¯the flow of runoff produced by a rain event equal to at least two times the 85th percentile hourly rainfall intensity for the applicable area, or ¯a rain event equal to at least 0.2 inches pr hour intensity. Operation and Maintenance of Treatment Measures: The Dischargers shall develop and implement a phased program to verify on a recurring basis that treatment BMPs are adequately operated and maintained. The operation and maintenance (O&M) verification program shall outline the conditions and procedures that will apply when the public agency is responsible and when a private entity is responsible for long-term O&M. At a minimum, the O&M verification program shall include maintenance of a listing of properties (public and private) and responsible operators, a plan for local agency inspection (e.g., random inspection of a subset of the listed properties), inspector training, follow-up procedures, and a commitment to periodic program evaluation. The schedule for phasing in the O&M verification program is based on the type of treatment BMP and is given in Provision C.3.o, Implementation Schedule. For all properties where a private entity is responsible for O&M, the verification shall include the owner or developer’s signed statement, as part of the project application, accepting responsibility for all treatment BMP maintenance until the time the property is transferred and ensuring that the initial and all subsequent transfers of the property to a successor private-or public owner will include conditions in the sales or lease agreement requiring the recipient to (1) assume responsibility for inspection and maintenance of all treatment BMPs at least once each year and (2) retain proof of such inspections. For Group 1 residential properties where a private entity is responsible for O&M, the verification shall include the owner or developer’s signed statement, as part of the project application, accepting responsibility for ensuring that printed educational materials accompany the initial and all subsequent deed transfers. The printed materials must: ¯provide information on what storm water management facilities are present; ¯explain the treatment BMP operation and maintenance requirements; ¯clearly illustrate signs that indicate maintenance is needed; ¯tell how the necessary maintenance can be performed; and ¯indicate what assistance the Discharger can provide. Where treatment BMPs are located within a common area that will be maintained by a homeowner’s association, language regarding the responsibility for maintenance must be included in the project’s conditions, covenants and restrictions. Reporting: The Dischargers shall report on their Treatment BMPs Operation and Maintenance verification programs in each Annual Report. Information to be reported should include the organizational structure of the program, its successes, and any problems along with possible solutions. Limitation on Increase of Peak Stormwater Runoff Discharge Rates: New development and redevelopment can impact water quality and beneficial uses of waters by altering a watershed’s patterns of runoff and particularly by increasing the rates, durations, and frequencies of peak flows. These impacts can result from individual projects and can occur cumulatively as the result of increasing urbanization of a watershed. It is the goal of this permit requirement to appropriately limit these changes where there is a potential for adverse impacts. Therefore, post-development peak stormwater runoff discharge rates and durations shall not exceed estimated pre-development rates and durations for new development and/or 8 redevelopment projects, where the increased peak storm water discharg_e rates and/or durations will result in increased., potential for erosion or other adverse iml?ac_t_s to beneficial uses. This limitation applies to all Group 1 Projects of Provision C.3.c, for all rain events which generate peak or near-peak flow rates and velocities less than or equal to a pre-. development rainfall event or events, or within a pre-development rainfall event range, to be determined by the Dischargers. This requirement does not apply to new development and redevelopment projects where the project discharges storm water runoff into creeks or storm drains where the potential for erosion is minimal. Such situations may include discharges into creeks that are concrete-lined or significantly hardened (e.g., with rip-rap, sackrete, etc.) to their outfall in San Francisco Bay, underground storm drains discharging to the Bay, and construction ofinfill projects in highly developed watersheds, where the potential for single-project and/or cumulative impacts is minimal. Guidelines for identification of such situations shall be included as a part of the Hydromodification Management Plan (HMP) required in this section. In addition, the HMP may identify conditions under which some increases in runoff may not have a potential for increased erosion or other impacts to beneficial uses. Reduced controls or no controls on peak storm water runoff discharge rates and/or durations may be appropriate in those cases, subject to the conditions in the HMP. In the absence of information demonstrating that changes in post-development runoff discharge rates and durations will not result in increased potential for erosion or other adverse impacts to beneficial uses, it is assumed that such impacts will occur. The Dischargers shall complete a review of the literature and develop an HMP. The HMP shall include: ¯the literature review; ¯a protocol to evaluate impacts; ¯identification of the rainfall event below which this limitation applies, or range of rainfall events to which this limitation applies; ¯a description of how the Dischargers will incorporate this requirement into their local approval processes; and guidance on management practices and measures to address identified impacts. The identified rainfall event or rainfall event range may be different for specific watersheds, streams, or stream reaches. Individual Dischargers may utilize the protocol to determine a site- or area-specific rainfall event standard. Interim standard: Prior to the Executive Officer’s acceptance of the HMP and a proposed standard, post-development peak storm water discharge rates and durations shall not exceed estimated pre-development rates and durations for new development and/or redevelopment projects for discharge from the 2-year storm up to the 10-year, 6- hour storm. Equivalent limitation of peak flow impacts: The Dischargers may develop an equivalent limitation protocol, as part of the HMP, to address impacts from changes in the volumes, velocities, and durations of peak flows through measures other than control of those volumes and durations. The protocol may allow increases in peak and near-peak flows and durations, subject to the implementation of specified BMPs and land planning practices that take into account expected stream change (e.g., increases in the cross- Sectional area of stream channel) resulting from changes in discharge rates and durations. The evaluation protocols, management measures, and other information in the HMP may include the following measures: Evaluation of the cumulative impacts of urbanization of a watershed on storm water discharge and stream morphology in the watershed; ¯Evaluation of stream form and condition, including slope, discharge, vegetation, underlying geology, and other information, as appropriate; ¯Implementation of measures to minimize impervious surfaces and directly cormected impervious area in new development and redevelopment projects; ¯Implementation of measures including storm water detention, retention, and infiltration; ¯Implementation of land use planning measures (e.g., stream buffers and stream restoration activities, including restoration-in-advance of floodplains, revegetation, etc.) to allow expected changes in stream channel cross sections, stream vegetation, and discharge rates, velocities, and durations without adverse impacts to stream beneficial uses; ¯A mechanism for pre- vs. post-project assessment to determine the effectiveness of the HMP and to allow amendment of the HMP, as appropriate; and, ¯Other measures, as appropriate. The HMP shall be completed as follows. All required documents shall be submitted acceptable to the Executive Officer. Development and implementation status shall be reported in the Dischargers’ Annual Reports, which shall a!so provide a summary of projects incorporating measures to address this section, and the measures used. No later than March 1, 2002: Submit a detailed workplan and schedule for completion of the literature review, development of a protocol to identify an appropriate limiting storm, development of guidance materials, and other required information; No later than September 15, 2002: Submit the required literature review; No later than March 1, 2003: Submit a draft HMP, including the analysis that identifies the appropriate limiting storm and the identified limiting storm event(s) or event range(s); and, ¯No later than July 15, 2003: Submit and fully implement the I-IMP, which shall include the requirements of this measure. Exemption or Waiver Based on Impracticability and Compensatory Mitigation: A Discharger m_m..a..~ through adoption of an ordinance or code incorporating the treatment requirements of this Provision, or by other formal administrative means, provide for a waiver from the requirement for treatment BMPs if impracticability for a specific project can be established. A waiver of impracticability shall be granted only when all treatment BMPs have been considered and rejected as infeasible. Grounds for impracticability may include: (i) extreme limitations of space for treatment on a redevelopment project, and 10 lack of below surface options, (ii) unfavorable or unstable soil conditions to attempt infiltration, and (iii) risk of ground water contamination because a known unconfined aquifer lies beneath the land surface or an existing or potential underground source of drinking water is less than ten (10) feet from the soil surface. Grounds (ii) and (iii) apply only to infiltration-based treatment measures, which are a subset of the range of treatment measure options, so do not in and of themselves establish impracticality. The Regional Board may consider amendment of Provision C.3.g submitted by a Discharger to authorize additional grounds of impracticability. The supplementary waiver justification becomes recognized and effective only after approval by the Regional Board or the Executive Officer. If a Discharger grants a waiver for impracticability, the Discharger must require the project proponent to transfer the savings in cost to a stormwater mitigation project to be used to promote regional or alternative solutions for stormwater pollution in the watershed of the development and operated by a public agency or a non-profit entity. The Discharger shall determine the amount of savings by any method that considers the costs of constructing and maintaining treatment BMPs in similar projects. Each year, each Discharger shall provide a list of the waivers it granted in its Annual Report. For each project granted a waiver, the following information shall be provided: ¯Name and location of the project for which the waiver was granted; " ¯Project type (e.g., restaurant, residence, shopping center) and size; ¯Percent impervious surface in final design; ¯Reason for granting the waiver; ¯Amount of dollar savings incurred by obtaining the waiver, with brief explanation of calculation method; and The stormwater mitigation project to which the savings was transferred. Alternative Certification of Adherence to Design Criteria for Stormwater Treatment Measures: In lieu of conducting detailed review to verify the adequacy of measures required pursuant to this Provision C.3.b-C.3.h, a Discharger may elect to accept a signed certification from a Civil Engineer or a Licensed Architect or Landscape Architect registered in the State of California, that the plan meets the criteria established herein. The Discharger should verify that each certifying person has been trained on BMP design for water quality not more than three years prior to the signature date, and that each certifying person understands the groundwater protection principles applicable to the project site (see Provision C.3.h Limitations on Use of Infiltration Treatment Measures). Training conducted by an organization with storm water BMP design expertise (e.g., a university, American Society of Civil Engineers, American Society of Landscape Architects, American Public Works Association, or the California Water Environment Association) may be considered qualifying. 11 Limitations on Use of Infiltration Treatment Measures - Infiltration and Groundwater Protection: In order to protect groundwater from pollutants that may be present in urban nmoff, the Dischargers shall ensure that treatment BMPs that f-unction primarily as infiltration devices (such as infiltration trenches and infiltration basins) meet, at a minimum, the following conditions:1 i.Pollution prevention and source control BMPs shall be implemented at a level appropriate to protect groundwater quality at sites where infiltration devices are to be used. ii. 111. Use of infiltration devices shall not cause or contribute to an exceedance of’ groundwater water quality objectives. Infiltration devices shall be adequately maintained to maximize pollutant removal capabilities. iv.The vertical distance fi’om the base of any infiltration device to the seasonal high groundwater mark shall be at least 10 feet. Note that some locations within the Dischargers’ jurisdiction are characterized by highly porous soils and/or a high groundwater table; in these areas BMP approvals should be subject to a higher level of analysis (e.g., considering the potential for pollutants such as on-site chemical use, the level ofpretreatment to be achieved, and similar factors).2 v. Unless stormwater is first pretreated, infiltration devices shall not be recommended for areas of industrial or light industrial activity; areas subject to high vehicular traffic (25,000 or greater average daily traffic on main roadway or 15,000 or more average daily traffic on any intersecting roadway); automotive repair shops; car washes; fleet storage areas (bus, truck, etc.); nurseries; and other high threat to water quality land uses and activities as designated by each Discharger. vi.Infiltration devices shall be located a minimum of 100 feet horizontally from any water supply wells. Site Design Measures Guidance and Standards Development: Opportunities to address stormwater pollution and hydromodification can be limited by current local design standards and guidance. For example, such standards and guidance may reduce or prohibit oppommities to minimize impervious surfaces, minimize directly connected impervious area, provide for small-scale detention, and implement other management measures. Revision of current standards and guidance can result in a significantly increased ability for project designers to minimize project impacts and can also increase local property values, neighborhood character, and overall quality of life. Further, revision of standards and guidance can allow implementation of site design measures in projects to meet or help meet the numeric sizing criteria in Provision C.3.d and/or the hydromodiflcation limitation in Provision C.3.f. 1 These conditions do not apply to structural treatment BMPs which allow incidental infiltration and are not designed to primarily function as infiltration devices (such as grassy swales, detention basins, vegetated buffer strips, constructed wetlands, etc.).2 See the June 1999 memo from Dan Cloak and Wendy Edde (SCVURPPP) to Municipal Planning Department Personnel, Additional Considerations for Incorporating BASMAA ’s Start at the Source Techniques in Development Projects for further information on the risks to groundwater and steps to take to minimize such dsks from infiltration of stormwater runoff. 12 Therefore, this measure requires that the Dischargers review their applicable local design standards and guidance to identify opportunities to revise those standards, where revision would result in reduced impacts to water quality and beneficial uses of waters, and that identified oppommities for revision be implemented. The following are examples of areas it may be appropriate to address in the review of- design standards and guidance: Minimize land disturbance; Minimize impervious surfaces (e.g., roadway width, driveway area, and parking lot area), especially directly connected impervious areas; - Minimum-impact street design standards for new development and redevelopment, including typical specifications (e.g., neo-traditional street design standards and/or street standards recently revised in other cities, including Portland, Oregon, and Vancouver, British Columbia); -Minimum-impact parking lot design standards, including parking space maximization within a given area, use of landscaping as a storm water drainage feature, use of pervious pavements, and parking maxima; Clustering of structures and pavement; Typical specifications or "acceptable design" guidelines for lot-level design measures, including: -Disconnected roof downspouts to splash blocks or "bubble-ups;" -Alternate driveway standards (e.g., wheelways, unit pavers, or other pervious pavements); - Microdetention, including landscape detention and use of cisterns. Preservation of high-quality open space; Maintenance and/or restoration of riparian areas and wetlands as project amenities, including establishing vegetated buffer zones to reduce runoff into waterways, allow for stream channel change as a stream’s contributing watershed urbanizes, and otherwise mitigate the effects of urban runoff on waters and beneficial uses of waters; and, Incorporation of supplemental controls to minimize changes in the volume, flow rate, timing, and duration of runoff, for a given precipitation event or events. These changes include cumulative hydrom0dification caused by site. development. Measures may include landscape-based measures or other features to reduce the velocity of, detain, and/or infiltrate stormwater runoff. The standards and guidance review shall be completed as follows. All required documents shall be submitted acceptable to the Executive Officer. A summary of review, revision, and implementation status shall be reported in the. Dischargers’ Annual Reports. No later than March 1, 2002: The Dischargers shall submit a detailed workplan and schedule for completion of the review, revision, and implementation of revised standards and guidance; 13 ko No later than September 15, 2003" The Dischargers shall submit a draft document that includes the review and analysis of local standards and guidance, opportunities for revision, and proposed revised standards and guidance; No later than September 15, 2004: The Dischargers shall incorporate any revised - standards and guidance into their local approval processes and shall be fully implementing the revised standards and guidance. Source Control Measures Guidance Development: The Dischargers shall complete a document providing draft conditions of approval for all Dischargers to use and to be incorporated into the enhanced New and Redevelopment Performance Standards. The document shall summarize source control requirements for new and redevelopment projects to limit pollutant generation, discharge, and runoff. Examples of conditions to be included and areas to be addressed include, but are not limited to: ¯Indoor mat/equipment wash racks for restaurants, or covered outdoor wash racks plumbed to the sanitary sewer; ¯Covered trash and food compactor enclosures with a sanitary sewer connection for dumpster drips and designed such that run-on to trash enclosure areas is avoided; ¯"Sanitary sewer drains for swimming pools; ¯Sanitary drained outdoor covered wash areas for vehicles, equipment, and accessories; Sanitary sewer drain .connections to take fire sprinkler test water; Storm drain system stenciling; Landscaping that minimizes irrigation and runoff, promotes surface infiltration where appropriate, minimizes the use of pesticides and fertilizers, and where feasible removes pollutants from storm water runoff; and, Appropriate covers, drains, and storage precautions for outdoor material storage areas, loading docks, repair/maintenance bays, and fueling areas. The draft conditions of approval document and enhanced Performance Standard shall be submitted by September 15, 2002, acceptable to the Executive Officer. The Dischargers shall have incorporated the conditions of approval document into their local approval processes and shall be fully implementing it by March 1, 2003. Implementation status shall be reported in the Dischargers’ Annual Reports, which shall also provide appropriate detail on projects incorporating the required conditions of approval. Revise General Plans: At the next scheduled revision of its General Plan or by July 1, 2005, whichever is sooner, each Discharger shall incorporate water quality and watershed protection principles and policies into its General Plan or equivalent plan (e.g., Comprehensive, Master, or Community Plan) as necessary to direct land-use decisions and require implementation of consistent water quality protection measures for all development projects. These principles and policies shall be designed to protect natural water bodies, reduce impervious land coverage, slow runoff, and where feasible, 14 ii. .oo 111. iv. Vo maximize opportunities for infiltration of rainwater into soil. Such water quality and watershed protection principles and policies may include the following, which are offered as examples: Minimize the amount of impervious surfaces and directly connected impervious surfaces in areas of new development and redevelopment and where feasible maximize on-site infiltration of runoff; vi. Implement pollution prevention methods supplemented by pollutant source controls and treatment. Use small collection strategies located at, or as close as possible to, the source (i.e., the point where water initially meets the ground) to minimize the transport -of urban runoff and pollutants offsite and into a Municipal Separate Storm Sewer System; vii. Preserve, and where possible, create or restore areas that provide important water quality benefits, such as riparian corridors, wetlands, and buffer zones. Encourage land acquisition of such areas; Limit disturbances of natural water bodies and natural drainage systems caused by development including roads, highways, and bridges; Prior to making land use decisions, utilize methods available to estimate increases in pollutant loads and flows resulting from projected future development. Require incorporation of structural and non-structural BMPs to mitigate the projected increases in pollutant loads and flows; Avoid development of areas that are particularly susceptible to erosion and sediment loss; or establish development guidance that identifies these areas and protects them from erosion and sediment loss; and Reduce pollutants associated with vehicles and increasing traffic resulting from development. m.Water Quality Review Processes: When Dischargers conduct environmental review of projects in their jurisdictions, the Dischargers shall conduct evaluations of water quality effects and identification of appropriate mitigation measures. The review shall address increased pollutants and flows from the proposed project through such questions as: Would the proposed project result in an increase in pollutant discharges to receiving waters? Consider water quality parameters such as temperature, dissolved oxygen, turbidity and other typical storm water pollutants (e.g., heavy metals, pathogens, petroleum derivatives, synthetic organics, sediment, nutrients, oxygen-demanding substances, and trash). ii.Would the proposed project result in significant alteration of receiving water quality during or following construction? iii.Would the proposed project result in increased impervious surfaces and associated increased nmoff? iv.Would the proposed project create a significant adverse environmental impact to drainage patterns due to changes in runoff flow rates or volumes? v. Would the proposed project result in increased erosion in its watershed? 15 vi.Is the project tributary to an already impaired water body, as listed on the Clean Water Act Section 303(d) list? If so, will it result in an increase in any pollutant for which the water body is already impaired? vii.Would the proposed project have a potentially significant environmental impact on surface water quality, to marine, fresh, or wetland waters? viii.Would the proposed project have a potentially significant adverse impact on ground water quality? ix.Will the proposed project cause or contribute to an exceedance of applicable surface or groundwater receiving water quality objectives or degradation of beneficial uses? Xo Oo Will the project impact aquatic, wetland, or riparian habitat? Reporting, including Pesticide Reduction Measures: The Dischargers shall demonstrate compliance with Provision C.3 by providing the following information in their Annual Reports for Group 1 and 2 Projects: Project name, type of project (using the categories in Provision C.3.c), site acreage or square footage, square footage of new impervious surface. Treatment BMPs and numeric sizing criteria used, O&M responsibility mechanism, site design measures used, and source control measures required. A summary of the types of pesticide reduction measures required (such as by conditions of approval) for new development and significant redevelopment projects, and the percentage of new development and significant redevelopment projects for which pesticide reduction measures were required. These measures are required under Provision C.9.d.ii, and relate directly to Provision C.3 requirements. In the September 2002 Annual Report only: A proposal for enhanced reporting to track the implementation of Provision C.3 requirements. The reporting shall include the above components at a minimum. Enhanced reporting for pesticide reduction measures may also be included. Implementation Schedule: The Dischargers shall implement the requirements of this Provision according to the following schedule: 16 Provision Action Implementation Date C.3.b Modify development project approval process as needed July 15, 2002 C.3.c.iii Report findings of new development and significant September 15, 2002- redevelopment project numbers, and sizes Propose an. alternative minimum project size proposal January 15, 2003 In absence of a proposed alternative minimum project size,July 15, 2003 Group 2 Project definition becomes Group 1 Project definition C.3.e Implement an O&M verification program for structural in-ground July 15, 2002 BMPs such as sand filters, filter inlets, detention/retention basins Implement an O&M verification program for landscape and all July 15, 2003 other BMPs, such as vegetated swales, dry or wet ponds Begin reporting on O&M verification program in Annual Report September 15, 2003 C.3.f Submit a detailed workplan and schedule March 1, 2002 Submit literature review September 15, 2002 .Submit draft Hydromodification Management Plan (HMP)March 1, 2003 Submit and implement final HMP July 15, 2003 C.3.g Report on any waiver(s) granted by the Discharger in Annual Begin the year a Report, due September 15 of each year waiver is granted c.3j Submit workplan and schedule for completion of review,March 1, 2002 revision, and implementation of design standards and guidance Submit draft proposal of revised standards and guidance September 15, 2003 Incorporate revisions into local process and fully implement site September 15, 2004 design standards and guidance C.3.k Submit draft conditions of approval document for source control September 15, 2002 measures. Implement source control measures guidance document March 1, 2003 C.3.1 Revise General Plans as necessary to direct land-use decisions July 1,2005 or at and require implementation of consistent water quality protection next scheduled measures for all development projects revision, whichever is first C.3.m Revise Environmental Review Processes March 1,2003 C.3.n Begin reporting Group 1 and 2 Project information in Annual September 15, 2002 Reports, and propose enhanced reporting method . Provision C.14 of Order No. 01-024 is hereby revised to read as follows: 14. This Order expires on June 1, 2006. The Dischargers must file a Report of Waste Discharge in accordance with Title 23, California Code of Regulations, not later than 360 days in advance of such date as application for reissuance of waste discharge requirements. ATTACHMENT B SANTA CLARA VALLEY URBAN RUNOFF POLLUTION PREVENTION PROGRAM DRAFT PERMIT LANGUAGE FOR CONTROL OF STORMWATER POLLUTION FROM NEW DEVELOPMENT AND RE-DEVELOPMENT SUMMARY OF KEY IMPLICATIONS FOR LOCAL GOVERNMENTS BACKGROUND The Santa Clara Valley Urban Runoff Pollution Prevention Program is a consortium of 13 cities and towns in Santa Clara County, as well as the County and the Santa Clara Valley Water District, that share a common permit to discharge stormwater to San Francisco Bay. These entities are referred to as "Co-permittees". The Program’s current permit requires mitigation of stormwater quality impacts of new and redevelopment to the "maximum extent practicable" (MEP). MEP is defined in the Program’s Performance Standards for Planning Procedures and Construction Inspection, which represent the level of implementation required by each Co- permittee. Currently, Co-permittees are requiring developers of projects with significant stormwater pollution potential (as defined in environmental reviews) to mitigate stormwater quality impacts using site planning and design techniques and/or permanent stormwater treatment control measures. These requirements apply to private and public projects. Planning or building department staff use internal guidance and professional judgment to determine which projects have significant impacts, and which types of stormwater controls are appropriate. PROPOSED PERMIT REVISIONS The Regional Water Quality Control Board has released a Tentative Order with proposed revisions to the requirements for new and redevelopment projects, including: Standards for sizin.q stormwater treatment controls so that 80 to 85% of the stormwater runoff from development sites each year gets treated, either through infiltration into surface soils, detention, or filtration in a treatment device. Limits on increases in peak stormwater discharqes from new or redevelopment sites that may increase erosion in creeks. The interim standard is that post-development peak stormwater discharges may not exceed pre-development peak discharges for storm sizes up to a 10-year recurrence interval (i.e., the stormwater discharge that will occur about once in 10 years).. Co-permittees are allowed to propose alternative creek-specific limitations using information from watershed assessments. Requirements for operation and maintenance of stormwater controls. Municipalities will need to: 1) require property owners/developers and successive owners to accept responsibility for maintenance; and 2) verify proper maintenance through a local agency inspection program. Definition of a minimum project size for which the design standards, peak flow limitations, and maintenance requirements apply. Initially, the standards will apply to all projects that create one acre (43,560 sq. ft.) or more of impervious surface (i.e, surface that does not allow water to infiltrate and thus creates runoff). After July 2003, the minimum project size will be reduced to include all projects that create 5,000 sq. ft. or more of impervious surface, unless Co-permittees propose an alternative minimum size definition that encompasses 80% of new impervious surface creation in a given year. Schedule for implementation. Co-permittees will have 1 year to modify development approval processes and begin the maintenance verification program; 1 ½ years to develop an alternative minimum size proposal; 2 years to submit alternative creek- specific peak flow limitations and draft revised local design standards; and 3 years to fully implement revised design standards and guidance. IMPLICATIONS TO MUNICIPAL PROGRAMS There will be significant costs to municipalities to develop procedures for, conduct training on, implement, oversee, and report on these programs. After July 2003, municipalities may need to conduct stormwater reviews of smaller, ministerial projects that currently only require a building permit, resulting in increased staffing requirements and permit delays. If infiltration is not practical on a development site, treatment measures such as detention ponds will likely be needed, which may create maintenance, vector control, and public safety problems. The cost of stormwater controls and the land needed to accommodate them may drive up the cost of housing, especially in high density developments, and may have a disproportionate impact on low-income and affordable housing. The requirements may impact the ability of a City to redevelop within downtown areas and drive more development to outlying areas.