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HomeMy WebLinkAbout0332.092j -I I 1 ! - (D. " ", "." :,' '. '" t July 9, 1992 THE HONORABL= CITY COG~CIL Palo Alto, califvrnia 12 DuDcan Place Bicycle/Pedestrian Bridge. elF 47102 -status R~port Arui Amendment No. 1 to Santa Clara Va 1 l!:'y_ h-ater District Aqr~ Members of the Council: Roport in Brief This report provides an update on the Duncan Place Bicyclel Pedestrian Bridge Project and recommends that Council authorize the City Manager or his designee to execute an amendment to Agreement No. C0017013 with the Santa Clare:. Valley Water District in an 3lJ10unt of up to $50,000 for design and construction of a modified :bridge and related i:rnproveme,Cits. Funds for this amendment ar-e a~ailable from CiP 47702. e a cJcqround As part of its flood control program, the Santa Clara Valley Water District (District) d~siqned a project to enlarge Adobe Creek to convey the lOO-year flood. Oue to the lack of space in the rear yards of properties abutting the creek, the District slected t.o construct new channel walls, ex~endinq several feet above ground level, rather than widen the channe14 Since the existing D~ncan Place bicycle/pedestrian bridg~ would have int~rfered with construc:tio!"l of the l"Jigher channel walls, the District agreeo to replace the City-owned bridge as part of its flood control projt";ct. The District proposed installing a p~efabricated bridge above the new channel walls, with concrete ramps leading down from the bridge to ground level~ Due to the impacts of the flood control project I the District conducted a public outreach progrell'. and prepared a tull environmental impact report (EIR), including an assessment of the new bridge, -which would now be 2.-1/2 f~.'et higher than the original bridge~ The EIR called for the installation of screen fencing on the bridge and along the ramps, to mitigate the resulting 106s of privacy for adjacent properties. In August 1990, council approved a cost-sharing agreement with the District for the replacement of Duncan Place bridge and approved st.,ff's de.termination that, the project was SUbject to a Class 2 -1- CMR: 332 :92 ······21·· _ categorical exemptior: from CEQA cnder State Guidelines section 15302. (CK.~: 464: 0). Under the t.er:ns of t~le agreetoe1'lt, the District is responsible (or the bridge replacement costs necessitateQ by the flood control work, • .... hile the City p~ys for the betterments in~luded in the project and the cost of the District's design and con~ract administ~ation services. council approved the agreement in the amount of $29,000, pased upon the uistriet~s cost esti~ate tor !:he bridge replacement~ After the District received bids for the work in 1991, the city's share ~a5 adjusted to $31,300. By early 1992, the District's contractor had completed all wcrk except the bridqe .i'eplacement and ne'W channel wall constructio.r'. i1lllO.ediately upstream of the bridge. {to~ard Al~a stree-.t). City staff became aware of the neighborhood's serious reservations over the bridge, vhile seeking temporary ea$e~~nts necessary to construct. the concrete ramps. In May 1992} Council received an informational r~port from staff outlining tne neighborhood's objections and describing a plan to h.:lst Ii corrur.uni ty D'leeting, in order to hear the public's conc~rns and suggestions (CMR:251:9~). The results of the 'lIleeting are described in the PDiscussion of Community Meeting-section belo~. In order t.o minimize delay and resulting contractor c:lairos, the District has allo~ed all work to proceed, with the exception of the bridge replaceruent and above-ground wall construction at the two properties on either side of the channel upstream of the bridge. This remaining construction has been rurposely held back to provide Council flexibility in pursuing any of the options described in the -Oiscussion of Alternatives" so:!ction below. In order to facilitate the channel construction, the contractor ..... as permitted to remo.e the old Duncan Place bridge on June 15. Statf developed a detour route for pedestrians and bicyclists travelling between the Greenmeadow and Walnut Grove neighborhoods and has posted di:rectional signs for the r',ew rOute tsee vicinity map~ Attachment A). Prior to the bridge closure, staff posted signs at the bridge and mailed notices to neighbo::-hood residentE, local 5ch.-:;.ols/P'l'A's, and the Palo Alto Bicycle Aovisary committee~ Piscussion of C~mmYDjty Meeting sta.ff hosted a cOrM.unity meeting to discuss the Duncan Place bridge on Wednesday, June 3, at the Cubberley Theater (see meeting sumroary, Attachment B). District staff -.. ere. also present to res~nd tc-questions on the project, flood control policy, and hydraulics~ The meeting was publicized in advance through notices Which vere mailed to all residents ..... ithin the area bounded by Charleston Road/N'elson DriveiSan Antonio Avenue/Alma Street, as well as the Grsenmeadow and Walnut Grove neighbor-hood associations, the Palo Alto Bicycle Advisory Comrr.ittee, and local schools and PTA's. Fifty-eight ~embers of the public attended the meeting~ -2- CMR:332:92 . ; ! - .city and; District staft openeci the meeting by des-:ribinq the background and current stat~s of the Duncan Place bridge replacement and outlining several alternative courses of action. Most of the session involved responding to questions and listening to comm-ant.li from the audience. Although various opinions wer'!:! expressed, there was rgeneral COT,sensus on the following key points concerning the bridge: • The Duncan Place bicycle/pedestrian br idge should ..:)e replaced. • The proposed design (installing th~ bridge above the raised channel 'Walls and providing screening fer privacy") is not acceptable. • The bridge should be installed as lev as pos6ible, that is, 'Within 6 inches of the original bridge elevation. The District should determine to what extent the upstream channel walls 'Would. need to be raised to contain the floodwaters which would be backed up kecause of a lower bridge. • The bridge should be. constructed at approximately the same vidth as the existing bridge (approximately 5 feet). • The bridge should be replaced as soon as possible (prior to school resuming in September, if feasib~e). Discussion of Alternatives After the community meeting, staff 'Worked with the District to develop a new alternative bridge design that will address the public's concerns. Staff has identified the fo110'"in9 alternative courses of action regarding the DUncan Place bridge: • Riqh Bridge Alternative (original D8siqn)= This alternative is to have the existinq contractor replace the Duncan Place bridge as originally dEsiqnej by the Distr-ict·. The alternative consists of a neW' a-foot-wide prefabricated bridge installed approximately 2-1/2 feet higher than the original bridge and requires construction of concrete ra.mps from the bridge do'wo'!l to ground level (see bridge profile, Attachm~nt C). In order to provide privacy to the adjacent homeowners, screen fenCing would be placed along the br-idge and its approach ramps. The screen fencing would be as much as 10 feet higher than existing ground level in adjacent residents' backyards. The massive structure could be viewed as a "walled tunnel n by bridge USo:lrs and result in lowered property values for adjacent homeowners. The ramps could promote skateboarding and make it mere difficult for persons with disabilities to use the bridge. For these reasons and -3- C1!R; 332: 92 - due to strong negative public sentiment. staff recommends 'aqi::dnst 'this alternative. • No Bridqe Alternative: Under this alternative.. Duncan Place Bridge \ltl'oul':i not be replaced. resulting in the loss of a convenient means of access between the Greenmeado ..... and walnut Grove neighborhoods, as well as a link in a City-designated bicycle route. Fifty­ two pedestrians and 139 bicyclists ~ere counted on the bridge during a 12-hour period on Tuesday, June 2. .'rea residents indicated that use of the bridge on the 'WeeJt::ends is even greater. If the bridge were eliminated, the closest crossings over Adobe creek would ~e at Charleston Road a~d Alma Street. The bicycle route could be changed to follow th.e temporary route currently in use but Would be less desirable because a seqment of it follo~s Charleston Road, a heavily-used arterial street. Staff does not support this altertlative because of its negative impacts on accessibility and safety. • Removable B~i4qe Alternative: This alternative consists of a replacement bridge installed at existing ground level that could be raised or ~emoved during high creek flows (e.g. a draw bridge, or sliding bridg<'!). The rationale for the alternative is that the bridge need not he elevated permanently above the channel, since the lOO-year flood is an infrequent event. This alternative eliminates the potential loss of privacy and the negative aesthetics of a higher bridge, while ~aintaining safe pedestrian and bicycle access. The removable bridge a1 ternati ve has several 'Weaknes:ies. First, the time spent researching and designing a remov~ble bridge would delay the replacement of the bridge '.lntil next year. !n additio~r the District has strong objections to the alternative, "ecallse of its reliance 0:1 human. intervention and its susceptibility to mechanical failure. If the bridge 'Were not removed during high creek flo'Ws. it could obstruct the flow of ~ater and cause upstream flooding. The District is unwilling to commit personnel to maintain and operate a removable bridge and ~ill not relinquish its responSibility for flood protection to another agency, such as the City. • At-Grade Bri~9. Alternative (Recommended Alternative): This alternative ~as developed in response to the public input received at the June 3 co~~unity meeting. It consists of a 5- foot-.... ide concrete bridge structure constructed integrally 'With the channel walls (see bridge cross-section, Attachment -4- CHP.: 332: 92 - .' OJ. The bridge would ~e built at the same elevation as the original ~ridge. The walls of th~ bridge wo~ld be built of solid concrete to the same height as the channel wa 116 in order to contain floodwaters. The need for concrete ramps and screen fencinq ~culd be eli~inated since the bridqe deck would be at approximately existing ground level. The bridge walls 'Would be 4 teet high 'With a safety railing on top. The railing will be either cpen or solid depenalnq on the need to prcvide additional privacy for adjacent homes. This could be determined after the b~ldqe is constructed. The at-grade bridge alternative impacts the-desiqr. of the creek channel itself. Since the lowered bridge could potentially act as an opstruction to flooQ~aters, the channel walls would need to be constructed approximately 5 feet above ths backyard ~round le:vel. ~~.P=t-::~~:::. ot the bridge. This would result in increasing the o~iqinal proposed wall height of 2 feet by approximately another 3 feet for four proper~ies (see loe ~ion map~ Attachment E;4 However, the 2-foot wall height at these four properties, as originally designed, was among thL lo'West ~lon9 the entire lenqth of the flood control project. Increasing their height to 5 feet will result in walls equivalent to tnose on adjacent properties. Staff has discussed the at-gracle bridqe ;:alternative with the three private property o'Wners affected by the change in vall height. (The City owns the fourth property). The two property o~ners immediately adjacent to the bridge are in support of the nev proposal. Due to the concerns of the third property owners, Mr. and Mrs. J~hn Wall, the Oistrict has r~evaluated their hydraulic analysis, and has dete~ined that the 'Wall height at th~t location can be reduced by 5 inches, thereoy resulting in a: 4-1/2 foot wall height (see wall profile, Attachment F). This is possible because the property is further upstream a~d subject to a lower level of water backup in the lOO-year flood event. Staff has made special efforts to find an engineering solution acceptable to this property o'Wner but have been unable to do so. An offer has bE-en made to provide landscaping along the back of the property to mitigate the effects of the higher wall~ however I to date, Mr. and Mrs~ Wall still do not support the at-grade bridge alternative, yhich results in the 4-1/2 foot-high wall behind their proper-ty. The District ca., design the at-grade bridqe alternative so that it can be installFd as a part of the District's current constructior. contract. It is anticipated that the bridge could be reopened for bicycles and pedestrians by mid-fall 1992. Staff has met with the residents liVing immediately adjacent to the bridge and the presidents of the Greenmeadow and Walnut Grove neighborhood associations to describe this -5- CKR:332:n alternative and. has received their support. !.s the design addresses all of the majol' issues raised in the public mee.tinq regarding the bridge J staff recommends this alternative. Discussion of R21ated Issues Several other related issues were raised by the publJc at the June J community meetinq. A list of these issues and staffJ s proposed. resolution are summarized below: • Bridge Appearance: In order to improve the aesthetics of the bridge discussed in the recommended alternative j the District will specify the use of brown-tinted concrete similar to that used for the Adobe Creek channel ~alls through Mitchell Park. In addition, the outer side of the bridge walls .""ill receive the sam~ architectural texturing used on the channel wa11s in the current project. • Bridge safety: Several neighborhood residents ~ere concerned that bicyclists and skatebcarders would not slow aown prior to .entering Duncan Place 3!1d Creekside Drive from the bridge sidewallc.. In response 1 baffles wi 11 be constructed at each end of the sidewalk near the street ~£ part of the recommended alt.ernative. 'rne baffles ... ill also disccul""age use of the path and bridge by motorized vehicles. • Bridge Width: The existing Duncan Place bl'idge and approaches are approximately 5 feet ...... ide. Under the original design approach~ the replacement bridge and approaches ...... ere to be buil t 8 feet wide in o!'der to conform to current State standards for t~o-w~y bicycle facilities. At the community meeting, there was a c1ear consensus to keep the bridge at its current width. Based upon operational considerations (safety and convenience) for the llsers J the Transportation Division staff recommendation is that the wIdth of the bridge should not he less than 6 feet. HO'Jever, since City-funded facilities are not obligated to conform to state standards and since the existing bridge ~lIlidth has net been a problem in the past l ~ 5-foot-vide bridge will ce installed. • Path Lighting: A suggestion ... as made to install low-level lighting tOl" night security. District personnel indicated that they did not have the in-house expertise to desjgn a lighting system for the project; and that time constraints preclude them from hiring a consultant to pcrfol'!II. the work. If directed by Council, staff would evaluate the need for lighti:l9 after the b:!"idge is inst.alled and develop a futL\re capital improvement p~oject for its implementation. -6- CMR: 332: 92 L Bicycle RI')ute: The DUncan Place bridge is currentll" pa:!'t of a desiqnat~d bicycle route bet~een San Antonio Avenue and the Bryant street eicycle Boulevard~ The bridqe is also used by local school children to acc-ess Jane Lathrop Stanford Middle School and Fairmrad'O· ... ElQmentary SchooL Several resid.ents su~qested that an alternate bicycle route be explored. The nearest adjacent crossings of Adobe Creek are located at Charleston Road and at Alma Street. Re.ro\Jtin~ i?icycle traffic via either of these alternative ccossings WOuld provide a less direct connection to the Br).-ant Street bicycle boulevard and Stanford Middle School and ~ould require cyclists to traY~l longer distances on a major arterial street. The bicycle route across the Duncan Place bridge has been in place since 19G2, and during the ensuinq y~ars the subject of relocatinq the bicycle route has not been raised as an issue. The bridge is used ~y a variety of people including neighborhood residents, school children, and recr~ational and commuter bicyclists. The total pedestrian/bicycle traffic on the bridge is relatively low for a Palo Alto bik~way. The existing alignment of the city bicycle route across the Duncan Place bridge is consistent wi th th~ adopted bikeway master plan, is convenient for both residents and most bicyclists and has operated successfully for the past decade. For these reasons and since the new bridge will not demonstrably alter the characte: of the bicycle route, Transportation Division staff finds no reasort t.o change the existing bicycle rou't.e at this time. However # if council wants to pursue an alternate route further, staff recommends that this be more appropriately considered in the larqer context of the. city' s bikeway master plan review that will take place during the Comprehensive Plan update. PiE:cussion of Ame1'1Q:ment It is recommended that Council authori~e the city Manager or his designee to execute an amendment to Agreement C0017013 with the District to incorporate the bridge and channel ... all elements discussed. in the At-Grade Bridge Alterr:.ative~ The maximum estimated city cost for the at-grade bridge and related improvements, including design and construction administration, is $81#3CO. The increase of $50,000 in City cost (from $31,300 to $81,300) is primarily dU2 to the construction of a new concrete bridqe, remobilization of the District's contractor, and District redesign/administration or the modified project. The District will be responsible for the cost of raiSing the channel ~al1s, removing the existinq bridge and reconstructing adjacent sidewalk. -7- Cl!R: 332: 92 - • The cost is based upon prel iminary estimates obtained from the Oistrict's contractor. However, the final City cost 'Will be detez.mined on the basis of actual expenditures incu::-red by tbe District for the work. The District will obtain a lump Bum price quote from their contractor so that the work can be performed via a change order to the existing contract. If the City and District agree that the contractor's price c;:uot~ is too high j the City has the option of requesting that the l)is-crict authorize the work on a time and materials basis. Staff also requests authority to 3mend the agreement regarding the ownership of the new Duncan Place bridge. Under the origir.al agreement, the bridge, which ~as to be free-standing and separate from the channel walls, ...... as to be o ... ned and maintairled by the City. Because the proposed at-grade bridge is to be constructed a& an integral part of the channel .... alls and. in effect, has a flood control function, staff recommends that ~he bridge be owned by the District. The District ~ould be responsible for maintenance of the concrete bridge st~~cture. The city would own and maintain the bridge railing above the concrete bridge walls and ~o·..lld be responsible tor the cleanliness of the bridge decK. Environml!!:ntal Asses.:?ment An addendum to the enviro~~ental impact report 'see Attachment G) has been prepared by the District in conjunction .it."l the City Attorney's office. It shows no substantial i~pacts resulting from the revised project. Recommendation staff recommends that Coun~il authorize the city Manager or his designee to execute an amendment to Agreement No. C001701J with the Santa Clara Valley Water District in an amount of up to $50 1 000 for design and construction of a modified Duncan Place bicycleipedestrian bridge and related improvements, (for a total maximum agreement amount of SSl,300} and further modify the agreement regarding ownership/!naintenance responsibili ties and such ot~er related matters as may arise during the negotiation of the amendment. Respectfully submitted j /,. £/ !Jr.¥a~/7~ GEORGE BAGDON Assistant Director of public Wor~s -8- CMR:3J2:92 - o '~~b'Ja~--• DAVID G. ADAMS Di~ector of Public Works , . . " lb-O---~ * cj WI LL AM ZANER City Manager Attachments; A. B. C. O. E. F. G. Relate1 Reports: Vicini~y map June 3 f 1992 community meetinq s~~ary Original bridge profile Bridge cross-section Location map Wall profile Addendum to Enviro~ental Impact Report CMR:464:0 CKR:251:92 ec: Residents adjacent to the bridge June 3, 1992 co~unity meeting attendees Gr~enmeadow Community Association Walnut Grove Homeowners Association Santa Clara Valley Water District JLS Middle School Fairmeaaow Elementary School JLS PTA president Fairmeado~ PTA President Palo Alto Bicycle Advisory CQmmittee city/School Traffic safety Committee -9- ~,332 :52 .''''''. ,.co -- .. :­ r ,r-. ATTACHMENT B CITY OF PALO ALTO DUNCAN.PlACE BICYC_LE/PEDJ;SIRfAN BAJDGE AITENDEES: City of Palo A!to sliLf1 Community Meeting June 3, 1992 7:00 PM MUTINJO SUMMARY George Bagdor'l, Assistant Director of Public \V.')rks Joe Teresi. Senior Enginoeer Man Costigan, Eng!neer Gayle Likens, Senior Planner .cJ.n£...2t.Palp Alto CouflcilfT'lemJl""l'.£.S. lanie Wheeler Joe Huber Sante Clara Vanev Wa:1M Distric1 Nai Hsueh, Flood Contre! DesJg'1 O:vis"ron Engrnee .... Randy Talley, F~ood Control Planning Division Engineer Roy Weese, Project Engineer Kurt Flammer, A.ssistant PfCjcct Engineer Tr . .:-community meeting '.vas Pllb~kcized in advarlce through mE!€tir"lg notices which we:e mailed tJali residents within the 2rea bounded by Charleston Rd.lNelson Dr./S-en Antonio Ave }AJmc St" as weH as the Greenmeadow a.nd Wainwt Gmve neighborhood associat:ons, the Palo Alto Bicycle Advisory Committee. and local schools and PTA's. Informational signs were posted at the bridge site. and a notice ."oIas publisrled' in the Palo Alto Wee!9:l. A total Of 58 members of the public attended the meeling. The meeting was conducted in accordance with the attached meeting agenda. It was divided into two major parts. The first pai"t consisted af a presentation by City and Water District stafi describing the background and current status of the propo~ed replacement of the Duncan Place bicycle/pedestrian bridge. City staff also outlined the previously identified key neighborhood concerns and discussed severar alternative Courses of act'lon. During the second part of the meeting, members of the public asked Questions and made comments concerning the bridge . - .-, _ ... ...-~'*.!'. IIIIf~n"', •• "'''i'iI'';''';i .. ",,;l;: OunC3Q Place SicycleJPedestrian Bridge Summary of June 3. 1992 Community MeetinG 1'89" 2 Public CgmmE}nts Ttle fonowing is a condensed list of the comments made b~' the pubUc at t,e community meeting: In order to slow down bicyclis1S and SKateboarders before they enter the: street, a set of bollards should be instailed at each end of the path. The boOard installation at the Oregon Expressway b!cycle(pedestrian overcrDssing is a good example to follow. The bridge is a valuable asset to the Greenmeadow and Walnut Groy~ neighborhoods and should be maintained. The bridge is a convenient way for children to traver across the creek without using Alma St. or eMsrleston Rd. rf the bridge were removed, it wouid li"Iake it ha{der for persons with disabil:ties to get arou nd t~ e ne i 9 h bo rhood. Aren't the br~dges at Alma St. and the railroad tracks constructed V'o"ith less than the standard amount of freeboard? If so, why can't the Duncan bridge be instafled at a lower elevation as well? The District answered that tf1e Duncan bridge could be lowered if 1) the channe! walls upstream of the bridge we,-e raised to accommodate the backed-up water, end 2) jf the b6dge were built with solid wails to contain the floodwaters to tne 5-=!me revel as the adjacent channe' walls. The amount of iJicycle and pedestrian traffic on the weekends is double the traffic on weekdays. Build the bridge at a lower etevation and deSign it to break away when it is inundated t.y flood waters, Don't widen the bridge to 8-feet; leave it at its current Width. Alma St. and Charleston Rd. are poor a!ternathle routes for bicyclists and pedestrians because they carry more auto traffic. The slope of the proposed bridge approach ramps is too steep for bicyclists, Eliminate the Duncan bridge from the City bicyde route network, The bridge is primarily a means fo( local tesidents to travel between the Greenmeadow and Walnut Grove neighborhoods. S·lcycfists should be able 10 use the bridge, but should not be directed to use it, ""'.~ .............. . . . -<-. ,. '. ---,,.,.', - Duncan Place Bicyclell'ed.strian Bridge Summary 01 Jun. 3. 1992 Community Meeting Page 3 Mar-y bicycliSts travelling across the Duncan bridge continue through the GreenfT1eadow community center, which 1s private property. It should be mad2 clear that the pathway through the center is not a City t,jcycfe rOllte. TextiJff!' the brkjge appraach ramps so that it wiil discourage use by skateboarders and roJ!erbIClders. but wiJ1 'Stili be usable by-bicycles, wheelchairs, and strollers. The proposed high screen fenclng will create a walled ttmnel that wiil be unsafe for young children. No one will be able to see in or out of this "tunnel". Make the bridge attractive, rather t"'an a waned tunnel. If the bridge is lowered, it wi!! be more likely to ::ollect and trap debris during heavy creek. flows, which could lead to large obstructions and flooding. The project shourd includ6 the installation of low profile lighting along the path in order to increase nighttime safety. The sfope of the proposed bridge approach ramps, although in cO!'"JfOfmar,ce with des;gn standards fo( persons with disabili.ti.e.s, would be very steep for persons in wheelchairs. The Impact of raising the height of the channef walls upstream of the bridge in order to anow for the Jowering of the Duncan bridge would not be significant, since many property owners are constructing six-foot-high wooden fences at the rt!ar of their yards anyway. The wooden fences would screen the higher channel walls from view. Users of the bridge make a lot of noise, sometimes even late at night. There is aiso a littering problem at the bridge. • ::~'. ~\; . ~"' J" o bun con Place Blcycle/Ped •• trian B:idge Summary of June 3, 1992 Community Meeting Page 4 ~eting Sum--.mary Although a variety of cpil1[ons were expressed by the public at the communit'y' meetiilQ.., there was general consensus en the foBowtng key points: 1. 2. 3. 4. 5. 6. The Duncan Place bicyclelpedesHian bridge snourd be rep~aced. The pm;>osed design (installing the bridge above the raised channel walls and providing screening fo,," privacy) is flO! acceptable. The bridge should be instaned as low as possible, preferably withrn 6" of the original {pre-earthquake)bridge elevattorl. The Water District should investigate furthsr the alternative of lowering the bridge, raising the channel wafls as required upstream, and designing a solid bridge that will contain the floodwaters 10 the same level as -;:he adjacent channel wcdts. The bridge should be constructed at approximately the same width as the existing bridge {approximately 5 feet). The bridge should be replaced as soon as possible iprior to school resuming in September, if feasible) and without a Significant cast increase to the City. The sxisting bicycle route betw~en Charleston Rd. and San Antonio Ave. shourd be rerouted so that it does not include the Duncan Place bridge. ~;j~; _ATTACHMENT C ~ ,'-", REMovE EXISTING WALK / 6' SCHEEN F"ENCING ~ NEW Ilf.TAWIHG IIALl 4n'RI\fOIf' fliU lUll !UGI; COllI' . !----------I i~II.III'[l lHI!,IG -NEw l@ti~~f.6i)nmuuu~~~i~~mt)J~--~ CljArlrl[l \.lrjj~jG \ \ I J ___ CREEKSIDE DRIVE BRIDGE PROFILE HIGH BRIDGE ALTERNATIVE iORIGINAL DESIGN) , ."." ~ .... J'.~~ ... ~~, NEW f1RIOGE T(JP ul" tiEw CQI'C, WALK ')~·~AMP ----- o I ) ') DUNCAN PLACE -- T: ~: " . ". ,,f/ "",_\\i' ! 1.5" CHAIN LINK FENCE i L ... .. .. ~, ATTACHMENT D ~ BRIDGE CROSS-SECTION AT-GRADE BRIOGE ALTERNATIVE . , .1> l'> ... · , CONCRETE BRIDGE ',:J • · v '1 ... --~-.~---.--.5'-O.--.. -.. ,------__ 1 ... .. · b. ' ., , , . ".';"::',1 f/ NEW BRIDGE OECI< AT SAME ELEVATION AS ORIGINAL BRIDGE f.. • .. , to " f,' "". ---.----~-~-----.-.. --~--------.~ .. ---,.- ."--CHANNEL WALLS BEYOND ~ / FUTURE BRIDGE RAIUNG TOP OF CHANNEL WALL , ;. ~ o '/' 1 . ' • . I , ATTACQENT E -LOCATION foIA."'- , .",n'" CHANNEL WALL HEIGHT TO BE INCRE~.SED PER AT-GRADE BRIDGE O\LTERNATIVE -(5EO: ATTACHMENT G FOR WALL PROFILEI _ .. ---_ .. --.-.------.---~ I! r li------------------ I; I- I I KYLE ~ w z z " '" u i PORTER TO CREEKSIOE OR ---- U'--i -- FAY ',,- ATTACHMENT F-WA.LL PROFILE I TOP 'W C~A~HE\. Wt..U. t!-ROPOSf.;,O DESlo,l'ol) l-!-j 1 i 3' -1" 2'-8" ~ 4-112' 1 -5' I ' u--------,. t -. -. ': l ~O~ O~ C~:N~'~ :A1~ ~OR~OI:A~ D~S~N~ •• - -0 OPPOO"".,, O"OUNO LO,"L"" t 1 •••••••.•••••••••••••••••••••••• 6.~ •••• ! .................................................................. ~ .......... ~ ............. , .......... . PORTER " ~-.--.-----.-g p.,PFROX\MAlE. (JRlJUND LEvEL --"\ ~ • FAY WALL 3'-1" _1-_ I lOP 01"" CHANNEL WAtl. {pqOf>OS£O DESIGN) ~ 5' /" TOP Or: CI~AN"IEL WALL IORIGINAl QHltiNI I .f ._. _ . _ •. . I i •••••••••••••••••••••• , •••••••••••••••••• , ..................................... I •••••••••••••••••••••••••••••••••••••• • ................... 01 •• ·.' KYLE MORRISON CPA .: d, , ., " o A'ITACtIME NT ~ Ac5dendup' to Environme:l1ta~ I.pAct Report to~ ~dobe __ cre.k Cha.nn.l~ovem&l1t_e .LCharl •• toil J:lcalS to 81 C'UI_ino Reali 'i'he District has reviewed the propos~d change in wall height ~djacent to the Wall property along Adobe Creek in the City of Palo Alto~ Based upon that review, it has been determined that neither a sUbsequent nor supplemental EIR is necessary, but that, pursuant to California Code ot .P.egulations, Title 14, section 15164, this document shall serve as an addeMdQ~ to the original EIR. The District finds that: l~ The change in wall height does not involve new significant envirorunental impacts not considered in the previous EIR. While the ~all height change may have some minor effect on the view fram Wallfs rear ) ... ard, that impact will be dg mini:mis in relation to the impacts previously considered; 2. The change in wall height does not constitute a substantial change with respect to the circumstances under 'Which the project is being undertal<eni 3. The change in wall height does not constitutp-new information of sUbstantial importance about the project. The District has considered this addendum in ccnjunction with the final E1R prior to approving any change in the }I.dobe Creek FlOOd Centrol Project l as required by the CEQA guidelin~s.