DRAFrDRAFT Lower Codomices Creek Improvements Plan Berkeley/Albany,Berkeley/Albany, California

May 1, 2001

Prepared By

TheThe Waterways Restoration InstituteInstihtte 1250 Addison Street, Suite 107 Berkeley, California 94702

FarWest Restoration Engineering 538 Santa Clara Avenue Alameda,Alameda, California 94501

Graphics and Editing:Editing: Katherine Mortimer, Planning Consultant

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CONTENTS

ExecutiveEx~ubveSunuruuy Surrunary ______1

1.0].0 Introduction. _.,-,______:-::-:-:--:______6 1.1] Project ParticParticipantsipants and Objectives 6

202.0 Background ______=_--,--______,------:::-______10 2.1 UniUniversityversity Village Master Plan 10]0 2.2 City of AlbanyAlbany Creek-Related P1arutingPlanning and ProjectsProj~ts 13 2.3 City of BerkelBerkeleeyy Creek-Related PlarutingPlanning andand Projects · 15 2.4 Trail 16 3.0 Goals ______1177

4.04.0 Hydrology and Stream Dynamics ::--:-:--:--=--,-______19 4.1 Equilibrium ~Stable"~Stablen Channel Conditions 19

55.0.0 Phased Creek Restoration Plan ______23 5.] Phase One Creek Improvements 23 5.2 Phase Two Creek Improvements 46 6.0 Riparian Corridor Design ______53

7.0 VegetationVegetation ManagementManagement and Channel Monitoring ______59 8.0 Permitting______-'-- ______62

9.0 ProjectProj~t CostsCosts, ______64

ReferencesRe£erences ______72

LIST OF FIGURES

1.0 INTRODUCTION Figure 1·1]-] Site Location l\.1aplVtap Figure 1-2 Project Location Map

202.0 BACKGROUND Figure 2-12-) UCBeB DevelopmentDevelopment SSiteite Plan: Step)Step I Figurguree 2-22-2 UCBeB Developmenlnt SiteSit e Plan: StepStep 2 Figuregure 2-3 City of AAllbbany BicycleBicycle Plan

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4.0 HYDROLOGY ANDAl'lDSfREAM SfREAM DYNAMlCS Figure 4·14-1 Meander and Channel Slope RestorationRestoration Figure 4-2 Geometry of MeandeMeandersrs

5.0 PHASED CREEK RESTORATION PLAN Figure 5-11865 US.US. Coast Survey Figure 5·219475-21947 Aerial Survey Figure 5-3 City of Berkeley Dept. of Engineering Meander, 5th ttoo 6th Streets Figure 5-4 Headcutting FigureFigure 5-5>5 Existing Conditions:Conditions: RR Tracks to 5th Street FigureFigure,5..6 5-6 Channel Design RR Tracks to 5th Street·PlanStreet-Plan and ProfileProfile:: Phase 1 Figure 5·75-7 Channel Design RR Tracks to 5th Street·CrossStreet-Cross Sections: Phase 1 FFigureigure s.s5-8 Existing Conditions: 5th to 7th StreetsStreets Figure 5·95-9 Rosgen Channel Type OassificationOassiIication Figure 5-5·10 Channel DesignDesign 5th to 7lh7th Streets·Streets - Plan and Profile:Profile: Phase 1 Figure 5-11,5..11 Channel Design 5th to 7th7t.h Streets - Cross Sections:Sections: Phase 1 Figure 5-12 Existing Conditions: 7th to 9th SStreetstreets FFigureigure 5-13 Channel Design 7th to 9th Streets - Plan and Profile: Phase 1 Figure 5·145-14 Channel Design 7m to 9th Streets - Cross Sections: PPhasehase 1 Figure 55·15-15 Existing Conditions: 9th Street to San Pablo Avenue · Figure 5-16 Channel Design 9th to San Pablo Avenue·Avenue · Plan and Profile: Phase 1 Figure 5-5·1717 Channel Design 9th to San Pablo Avenue - Cross Sections: Phase 1 Figure 5-185·18 Channel Design 5th ttoo 7th Streets - Plan and Profile: Phase 2 Figure 5-19 Channel Design 5th to 7th71t1 Streets - Cross Sections:Sections: Phase 2

LISLISTT OF TABLES

TTablablee 6·16-1 : Restoration Plant Species Table 9·19-1 : Design·SuildDesign-Build Construction and Project ImplementationImplementation Costs TableTable 8-B·1:1: ChaChannnnel Design Worksheet Table C-1:ComComparisonparison of Estimated Peak Flow Discharges

LIST OF APPENDICES

Appendix A: ListList of Related Studies, Reports and Projects Appendix B: Stable Channel Design Process Appendix C: Flood Peaks for CodoCodomicesmices CreekCreek

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EXECUTIVE SUMMARY

The University of California, Berkeley (UCB), the City of Albany, and the City of Berkeley jointljointlyy authorized and funded this plan to improve Codornices Creek to a more natural statestate,, including steps that can be taken in the short-term to imprimproveove the creek given exexistingisting conditions and constraints. The plan encompasses the half­ mile reach of the creek that runs from the Southern Pacific Railroad Tracks east of Interstate 80 to San Pablo Avenue. The creek forms the boundary bet"veenbetween thethe cities of Albany and BerkeleyBerkeley.. University Village, 9209201: ± units of student family housing,housing. is north of the creek in Albany. South of the creek in BerkelBerkeleyey are several commercial and light industrial uses, a United States Post Office package facility, and a newly developed City of Berkeley recreation field complex.complex. A number of groups have an interest in this creek planning.planning, indudingincluding representativesrepresentatives of various creek organizations and field user groups,groups, bicyclebicycle advocates, Village residentsresidents,, and nearby property owners.

The UC Berkeley Campus is impimplementinglementing ththee University Village Master Plan to replace its aging housing at University Village and replace or renovate relrelatedated community facilities. While the existing housing and some facilities present impediments to restoring the creek, the implemimplementation of the Master Plan will provide opportunities to increase the creek right-of-wayright-of-way in selected constricted reachesreaches.. ImprovImprovementsements to the creek to proprovidevide for flood controlcontrol for the recently completed Step 1 of the redevelopmentredevelopment project, and to allow for tthehe replacement of the remaining housinghousing (Step 2),2), are also included in the plan.

Four sports fields at University Village will need to be relocated in order to complete implementation of the Master Plan,Plan. and thethe City of Albany is working with the university to insure that the field users will have continuity of field use throughout the process. The proposed plan is to relocate the existing littllittlee league fields and softballsoftball field to the Dowling Park area on the western edge of the Village, and to reconfigure the largerlarger soccer field from an easteast-west-west to a north-southnorth-south orientation.orientation. This will displacedisplace the existing University BiIlageBillage garden from Dowling Park, for which an altemativealternative location is being explored. In addition,addition. proprovidingviding sufficient land for the fields will require culverting and/and/ or redirecting the portion of Village Creek that runs along the SPRR tracks on the western edge of Dowling Park.

The City of Albany has been active in efforts to restore the fourfOUI creeks in, or forming the border of, the city,city, and votersvoters approved bond funding for both creeks and fields. More recently, the CCityity has secured funding to support efforts to developdevelop a bike trail along CodomicesCodornices Creek that would connect most of Albany's populationpopulation with the relocated youth sports fields and ultimatelyultimately,, the Bay Trail, and another grant to fund some of the creek restoration.restoration.

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The city of Berkeley has been actively invoinvollvedved in efforts to improve CodornicesCodomices CreekCreek,, especially as it relates to flood control for adjacent andand downstream proppropeerties. In the fall and winter of 1991997-98,7-98, ththee city funded a channel rrestorationestoration projprojectect between 5th and 6th StteetsStreets to relieverelieve bank erosion and floodingflooding problproblems.ems. ThThee citydty recentlyrecently purpurchasedchased ththee prpropertyoperty oonn the south side of the ccreekreek from 5th Street to the railroadrailroad tracks toto develop youthyouth sports facilities and aJlocatedallocated a portionportion of that land to future creekcreek rrestorationestoration efforts. Berkeley has also adoadoptedpted a bicycle plan to encourageencourage greater bicycle useuse for both conunuting and recreatiorecreationn throughoutthroughout thethe city.

Goals

The universityuniversity,, cities ooff Albany and BBerkeleerkeley, and relatedrelated interest groups identified the following goals for the creek planningplanning::

• RestoreRestore Codomices Creek to as nanaturaltural a statestate as popossissibleble • DevelopDevelop a regional trail ttoo link to the Bay TrailTrail toto the west and the BART trail to the east. • RRelocateelocate softball field aandnd reorient soccer fields to allallowow forfor housinghOUSing redevelopment • ReloRelocatecate village gardensgardens • Relocate littleHttle leagueleague fields toto provide suffidentsuffident depth along San Pablo frontage toto attractattract appropriate commerciaconunercial development • ProProvidevide access to relocated softbalsoftballl and littlelittle league basebabaseball fieldsfields • Provide forfor University Village hhousinousingg redevelopmentredevelopment flood controlcontrol and flood control for properties in BBerkeleyerkeley sosouthuth of ththee Creek • ReduceRed uce,, to the extent ppossibleossible,, floodingflooding impacts on upupstreamstream and downstream properties • PProtectrotect and restore steelhead andand otherother aquatic habitat • Correct existingexisting streamstream channelchannel instabilities • ResRestoretore Codomices Creek channelchaIUlei andand riparian corridor as mitigatiomitigationn forfor the loss of existingexisting channels onon Village Creek and the CodomicesCodorruces by-pass-pass channelharmel • AvoAvoidid causicausingng unduunduee cost ttoo ththee University Village hOUSinghOUSing redevelopmentopment bUdget • Minimize project costs to the degree feasible • Provide some habitat for wildlife aandnd some remnaemnantnt ooff ththee histhistoricoric ripaririparianan environment • EEvaluatevaluate flofloodingoding impacts of thethe proposed creek restoration design onon adjacent propertiesproperties

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The Plan

The CodornicesCodorruces Creek plan describes the creek restorationrestoration and bicycle/bicycle/ pedestrian trail development in two phasesphases:: Phasel and Phase2. In Phase 1, the plan assumes that major improvements to most of the reaches can be made as the University proceeds with its plans for redeveloping its San Pablo frontage in conjunction with a private developer. Significant work on the reach betw'een 5th and 6th streets cannot be achieved until Step 2 of the housing redevelopment proceedsproceeds,.. and will require a revision to the step 2 site plan in order to avoid a loss in unitsunits.. Thus,Thus, the plan would be impimplemented.lemented. in two phases. Phase 1 workwork would only be accomplished when additional right-of-way becomes aavailable.vailable. Phase 1 of the plan also assumes that the UU.S..S. Post Office will cooperate with these efforts by making additional landland available for the reach betweenbet\'veen 6th and 8th streets. There are no plans to move existing ccommeommercialrcial buildings onon the BerkeleBerkeleyy side.

The planplan does not represent the restorationrestoration of the historical conditions of the creek but it does apply geomorphic principprinciplesles to restorestorere some of the structure, functions and diversity associated with the historical creek environment.environment

Steps to implement the first phase of the project,project, by reach, include:

SP Railroad Tracks to 5th Street • Remove and/orand/ or plug Codornices Creek bypass. • Relocate softball field to Dowling Park; reorientreorient soccer field to north-south didirectionrection • Relocate fieldfield house • Remove concrete culvert and restorestorere channel to natural meander • Construct a vehicle/ bicyclebicycle/ pedestrian bridge over creek at 5th Street • Add a pedestrian path along the north side of creek

5th to 6th streets • Install soil bioengineering systems [list specifics] • Restore 200 feet of creek in location of thethe bbypassypass • Remove bypass headwall

6th to 8th streets • Culvert or relocaterelocate VVillageillage Creek • RRelocateelocate the two Little leagueLeague fields to Dowling Park (north). • Relocate the grounds storage building that is located adjacent to the creek in the San Pablo Avenue frontage corrunercial development. • Relocate portion of Albany Children's Center play yard yard and a storage buildingbuilding.. • Restore Codomices CreekCreek between 6th and 8th Streets

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• Develop bike.trail on south side of creek.

8th to 9th streets • Minor trail improveimprovementsments

10th Street to San Pablo Avenue • Relocate the LittlLittlee League fields (above)(above).. • Remove existing UCB student housing units along San Pablo Avenue as part of commercial development (lease) • Restore CoCodomicesdomices Creek from San Pablo AvenueAvenue to Tenth Street • Remove 10th Street culvertcuI vert • Develop bike trtrailail connecting San Pablo to the creek

Steps ttoo implement the second.second phase are:

5th to 6th streets • Remove University Village housing along Codornices Creek bet\veenbetween Fifth and Sixth Streets • Remove the Sixth Street culvert • Increase right-of-wayright~of-way for creek improvements • Add pedestrian floodplain trail

RevegetationRevegetation andand Monitoring Plan

The plan also includes a revegetation strategy that would emphasize removing invasive plants and establishingestabliShing native riparian canopy shade trees along the northnorth and south banks. Plantings would maximize the diversity of native species. The stand of elm trees in the 10th Street to San Pablo reach would be rretained,etained, while managing for succession to native spspecies.ecies. The banks and floodfloodplain plain wouwouldld be graded toto promote variations in slopeslope and encourage species diversity.diverSity. The planplan also calls for encouraging volunteer participationparticipation in planting projects by University Village and residents of the larger conununities.communities. The maintenance and monitoring component is designed to insinsureure that the creek is rrespondingesponding to the design parameters and the vegetation is successful.

Costs

TheThe preliminary cost estimate for constructing the improvements is $1.38 million. ThTheseese costs include final design, projectproject management,management, planning,planning, construction, and post construction management and monitoringmOnitoring. Costs for culvert removals need to be finalized basedbased. on alternative disposal and/ or burial scenarios.

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Next Steps

The city of Albany has eengagedngaged a consultant to analyze the potential environmentalenvironmental impacts associated with implementing the creek plan and associatedassociated field development. The consultant will prepare an InitialInitial Study to identify potential impacts and determine the llevelevel of environmental reviewreview that will be required under the California Environmental Quality Act (CEQA) and the National Environmental Protection Act (NEPA).

Concurrently, permit applications will be submitted to the relevantrelevant agencies-the San Francisco Bay Regional Water QuaQualitylity Control BoardBoard,, the Army Corps of EngineeEngineers,rs, and the Department of Fish and Game. The National Marine Fisheries Service and the U.S. Fish and Wildlife Service may provide input as part of the Army Corps of EnginEngineerseers permitting process. Although the permit applications can be submitted to begin the permitting process, no permits can be issued until completion of the environmentalenvironmental review. ImplementationImplementation of the creek planplan and relatedrelated bike trail improvements and field relocationrelocation will be coordinated with the field user groups so as to avoid disruptingdisrupting theirtheir season. CCreekreek restoration construction activities will also need to be scheduled.scheduled according to permit requirrequirements.ements.

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1.0 INTRODUCTIONINTRODUCTION

This report was jointljointlyy authorized and funded by three public agenciesagencies-the--the University of California, Berkeley (UCB), the Gty of Albany,Albany, and the Gty of Berkeley-to develop both a long-rangelong· range design for Codomices Creek intended to maximize restoration ooff the creek to a more natural statestate,, and a shoshort-rangert·range plan that recognizes the reality of existing conditionsconditions and constraints. This report makes recommendations regarding incrementalincremental steps that can restore reachesreaches of the creek, provide flood protection, and respect the land use objectives of adjacent property owners.

Codornices Creek is an urbanized creek demarcating the bordborderer of the cities of Berkeley and AlbanyAlbany,, California. The creek flows from steep drainages in the Berkeley Hills through the city flatlands and into San Francisco Bay, where itit is tidanytidally influenced in the very llowerower reaches. Although significantly altered over time bbyy channelization,channelization, culvemngculverting and straighteningstraightening, CodCodomicesornices Creek is the only creek leleftft in the cities ofof AlbanyAlbany and BerkeleyBerkeley in which the majority of its llengthength is an open channel and has not been converted to storm drain piping, and thereforetherefore represents the best opportunity in this area to restore natural creek functions 'Nithinwithin an urban envirorunent_. It is a principal feature of parks in the BerkeleBerkeleyy Hills (Codomices(Codomices Park,Park, thethe Rose Garden,Garden. LiveLive Oak Park) and a focalfocal interest of local creek groups at the BARBARTT greenway in Albany.

The reach of Codornices whichwhich is the subject of this report is a half mile stretch from ththee Southern Pacific Railroad Tracks east of InterstatInterstatee 80 to San Pablo Avenue. The Regents of the University of California 0\0\'0O\o\'ll the Albany side of the creek.creek, which is developed with student familyfamily housing, kr\o\o\'Ilk.r)o\o\'o as UniversityUniversity Village. The south ssideide of the creek is mostlmostlyy developed with commercial and light industrial uses, with a new yoyouthuth sports facility complex at the lower end of the study area. The property owners on the south ssideide include the City of Berkeley,Berkeley, the U.S. Postal serviceservice,, and a \'aarietrietyy ofof residential,residential, indindustrialustrial, and commercial landowners. The creek drains a "'wate·.ltershed of approximatelyapproximately 11.2.2 square miles andand. collectscollects stonnstonn water from varivariau~ou!O Jr.llnagedr.:una~e systems (Figures 1-1 and 1-2).1·2). Much of the existing development illil l (1(ln~n ~ the'the- creek is veryvery close to the creek bank, iimpedingmpeding the potential for creek restrestorJIi('lOo rJh~)n

1.1 Project POirtLClpantsPOI rllclrOinu and Objectives

The Codomicl"S Creek team consists ofof representatives from UCSUCB, the CityGty of AlbanyAlbany and the City of Berkeley.y. The team ffirstirst met in the spring ofof 1999 to collaborate on a creek restoration plan for CodornkesCodomkes Creek from San Pablo A venue

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AR 007425 Site Location Map Figure 1-1

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Ulti,·ersityUniversity Village"VllIage &: AJbaayA1baDY {I NorthwestNo rthwest 8t'rkewyBerkt~y PropertiONProper1iel Master PlanPlao LOCATION MAP

Source;Source; UC Berkeley

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to the Southern Pacific RailrRailroadoad (SPRR) tracks above 1-80. In that efforteffort the team identified the rights-of-wayrights~of~way needed to accaccomplishomplish the plan,plan, as well as the existing conditions that would interferinterferee with its implementation. The team approach to planningplanning for the creeks and channels is being continued ttoo provide for coordinated.coordinated project designdesign,, permitting and stakeholder iinvolvementnvolvement in planning and implementation.implementation. Among the stakeholdersstakeholders are the Associated Sports Fielieldd Users, Albany ball field advocates, representatives from Building Opportunities for Self­· Support (BOSS), skateooarders,skateboarders, University Village community gardeners,gardeners, Friends of FiveFive Creeks, the Urban CreeksCreeks Council, University Village residents and staff, bicycle advocates, and some Berkeley privateprivate property owners.

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2.02.0 BACKGROUND

Several recent projects and planning processes have had a direct or indirect impaimpactct on Codornices, as well as Village, Creek. These events provide an opportunity, and challengesenges,, to make improvements to the creeks.

2.1 University Village MMasteraster Plan

The BerkeleBerkeleyy Campus is implementiimplementingng a master plan to replareplacece 420 units of student family housing constructed during the second World War (Step 1 of UniversityUniversity Village HousingHousing Replacement Project) (Figure 22.1)-1); replace and/orand/ or renovate an additioadditionanall 500 units dating from the early 1960,1960s (Step(Srep 2) (Figure 2-2); and replace or renovate related community facilities constructed in the 19405 (Step 3).

University housing projects must be self·suppomng,self-supporting, and the universityuniversity makes every attempt to offer hOUSinghousing bebelowlow prevailing market rates. In order to contrcontribibuteute to this effort, the plan designated properties along HarriHarrisonson Street in BerkeleBerkeleyy to be sold and land along San Pablo Avenue leased for commercial development to generate income to help fund the new housing.housing. Since the plan was approapproved,ved, the university sold these properties to the United States Post Office and the City of BerkeleyBerkeley..

A third ellementement of the pplan,lan. again to provide financial support for thethe overall hohousingusing rederedevelopmentvelopment project, isis to lease property fronting on San Pablo Avenue for private development. Step 3 of the project, replacingreplacing the Village community facilities, will become the responsiibilitybility of the prpriivatevate developer.

As part ofof the Step 1 hhOUSingOUSing projectproject,, the university opened up a reach of Village Creek in the spring of 11999999,, rrelocatingelocating it to the northern edge of University Village from JJaacksocksonn SStreettreet west to the eastern border of the USDA property. Possible fl ood controlcontrol improvements to Codomices Creek in ssupportupport of thethe recently completed Step 1 houhousingsing projec t are included in this report.

222.2 City of AlbanAlbanyy Creek-Related Planning and ProProjectsjects

The CityGty of Albany has alwaysalways been an avviidd supporter of maintaining existing,existing. and where possible increasing, ththee amount of field space availabavailablele for youuthth. Similarly, the city has been active in efforts to restore the four creeks in,in, oror forming the border of, the city. The City'sGty's WatersWatershedhed ManagementManagement Plan recommends stream restoration of Codornices Creek. In 19%,19%. Albany vovotersters passed a measure providingproviding funds foforr both fields and creek restoration effortsefforts.. The city is currently participating in an effort to restore CodomicesCodornices Creek between San Pablo Avenue and Kains Street at the Resources forfor Community DeveloDevelopmentpment affaffordableordable hOUSinghOUSing developmedevelopment.nt

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AR 007429 UCB Development Site Plan (Step 1) FigureFigure 2-1 i ~. '~~{PI 1 p I I - I -ng "'! ! "

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AR 007430 UCB Development Site Plan (Step 2) Figure 2-22-2

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MoreMore recently, the city has secured funding to support efforts to develop a bike trail along Codomices CreekCreek that would connect most of AlbanAlbany'sy's population with the relocated youth sports fields and provide an important link between the OOhlonehlone Greenway (BART trail) and the Bay Trail. Such a trail would contribute to Albany'sAlbany's efforts to provide access to the creek while encouraging the use of alternative forms of transportation through their proposed bike trail system. (Figure 2-3)

The University in the past allowed.allowed community youyouthth sports fieldsfields to be developed on its property in Albany when the demand for use ooff that property,property was not as great as it is today. There are currentlcurrentlyy two littlelittle league baseball fields, one softball field vvithwith an overlapping practice soccer field, and one soccer field on the university property wwithinithin the City of AAlbany.lbany. In responseresponse to concerns from the city and sports field users, the university included in its University ViUageVillage Master Plan a commitment to make land available to replace youthyouth sports fields that would need to be relocated to allow for the housing redevelopmentredevelopment and associated.associated commercial development.

Step 2 of the housinghOUSing replacemreplacementent project includes the construction of housing on the soccer and softball fields site. Providing an appropriate site (sufficiently deep) for commercial ddevelopmentevelopment along the San Pablo frontage will require the rerelocationlocation of thethe two BerkeleyBerkeley-Albany-Albany Little League fieldsfields locatedlocated iinn Albany.any. In 1998 the City of AlbanyAJbany established a Recreational Playfield Task force to coordinate a lalarrge group of AlbanAlbanyy''ss sports groupsgroups and creek organizations to resolvresolvee land use issues at Dowling Park and the existing softball and soccer fields. A schematic master plan is stillstill under consideration The proposed plan is to relocate the baseball and softball fieldsfie1d s to ththee Dowling Park area on the western edge of the VillageVillage,, andand. toto reconfigure the larger soccer field from an east-west to a north-southnorth-south orientation. Negotiations between the university and the City of Albany to resolve outstanding issues,issues, such as access to the fiefieldslds, areare underway.undervvay. Providing sufficient landland for the fields will require culvertingadverting and! or redirecting the portion of Village Creek that runs alongalong the SPRR tracks on the western edge ofQf Dowling Park. The field rerelocationlocation willwill also displace the UniversityUniversity Village corrununal gardens, for which an alternative llocaocationtion is being sought.

22.3.3 City ooff BerkeleyBerkeley CreekCreek-Relatlateed PPlanninglanning and ProProjjects

The City of Berkeley has been actively involved.involved in efforts to improve Codornices Creek, especially as itit relates to flood control for adjacent and downstream propertiesproperties. The city constructed a storm sewer addition under Harrison Street from Fifth Street to connect with the Gilman Street sewer in falfalll 1997 to alleviate storm water based flooding from Fifth Street to the SPRR tracks. [n[n the fa ll and winter of 19971997-98-98, Berke1eyBerkeley sponsored and funded a channelchaMe1 restoration project between Fifth

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AR 007432 City of Albany Bicycle Plan Figure 2-3

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and Sixth StStreetsreets to relierelieveve bank erosion and flooding problems. The cross·cross·sectional sectional area was increased by over 100 square feet, forfor a 40-50% increase,increase, and as much channel length as possibpossiblele was restored. The project required excavating layers of"of "sackcre sackcrete",te", old pipes,pipes, rubbrubblele and debris that had been thrown into the channelchaIU1el over time.

The City of Berkeley purchased the property on the south side of the creek from 5th Street to the railroad tracks to develop additional youth sports facilities. The field design included using the property as a short-term flood.flood plain to handle creek overflows, babalancinglancing the need to control downstream flooding with that of draining the fields within a short time frame so as not to damage the turf. The fiefieldld layout was designed to allow for a wide creek meander where posspossible,ible, particularly towards the western half of the property, anticipating future restoration.restoration

The City of Berkeley has also adopted a bibicyclecycle plan to encourage greater bicycle use for both commuting and recreation throughout the city. They share AlbanyAlbany's's interest in providing a bike/bike! pedestrian trail as alternative transportation access and an amenity for the new sports complex and the BBaayy Trail.

2.4 TraTrailil

One of the importantimportant objectives of this project for the cities of Albany and Berkeley is to provide a trail and public access along the creek. This traitraill can serve as a vviabiable alternative transportation link from the now completed Bay TraiTraill immediately downstream of this site. A study isis undenvayunderway to assess the feaSibility of locating an East Bay ferry terminal at the foot of Gilman Street. This possibility magnifies the benefits of a trail that can link this transportationtraruportation system to the OhIone Greenway r" trail in Albany leadingleading to the North Berkeley BART., and ultimately to the University of California, Berkeley campus. The plan contains a 12-foot right-of-way for a pedestrian/bicycle trail, which meets CalTrans design requirements that would also serve as access for creek maintenance,maintenance, along most of the restored creek. Due to limited riighghtt-of-wof-way,ay, there would only be a pedestrian path pprovidedrovided between 5th and 6th Streets to provprovideide accessaccess to the athletic fiefieldld located west of 5th Street.

2.52.5 CommCommunity-Sponsoredunity-Sponsored CCreekreek ImImprovementsprovements , Beginning in the fall of 11995995,, severaseverall nonprofit groups (Urban Creeks Council, Friends of Five Creeks, Americorps, Urban Ecology and Ecocity BUilders) removed the underground culvert between Eighth and Ninth Streets and restored this reachreach of Codornices Creek to an open channechanneLl. The university cooperated with these efforts by eliminating parking spaces to allow for a better channel meander than would have otherwiseothenvise been impossible, and completed fencing and creek access projects. However, the creek restoration ddidid not meet basic channel stabilitystability needs , i' i Waterways Restoration IInstitutenstitute 1IS5 ,I" Lt

AR 007434 DRAFT 3/13/1/01 Phased Creek ImprovementsImprovements and serious erosion problemsproblems havhavee resultedresulted.. Despite efforts to widen and vegetate the channelchannel using soil bioengineeringbioengineering planting methods,methods, tthehe channel continues to show head ccuttingutting and erosion problems. Despite thesethese problems, this reach of the creek has become a well·usedwell-used commcommunityunity resource.

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DRCRAAFTFT 31110311f011 Phased CCreekreek Improvemertsfmprovemerts

3.03.0 GGOALSOALS

Each entity hhasas specific issues that need to be considered in a creek restoration plan. The goal of the planning process is to developdevelop consensusConsensus and permitablepennitable plans to restore the channels, floodplains and wetwetlandslands of lower CodomicesCodornices Creek and address Village Creek issues while meeting the priority land use objectives of the stakeholders. Combining the goals of the university and the citiesdties of Albany and Berkeley with those of the various stakeholders resulted in the followingfollowing creek·creek. rerelatedlated goals:goals:

•I Restore Codomices Creek to as natural a state as possible.possible.

• DDeveevellopop a regioegionalnal trail along CodomicesCodornices Creek that links to the Bay Trail to the west and thethe BART trail corridor to the easteast..

• Relocate the softball field and reorient the soccer field in AlbanyAlbany for housing redeveredevelopment.lopment.

• Relocate the University Village communal gardens from Dowling Park

• ReRelocatelocate little league fields to provide sufficient depth along San Pablo frontage to attract appropriate commercial devedevelopment.lopment.

• Provide access to relocated softballsoftbaU and littletittle league baseball fields.

• Provide for University Village hhousingousing redevelopment floodflood. control.

• Reduce, to the extent possible, flooding impacts onOn uuppstreamstream and downstream p~opertiesproperties.

• Protect and restore steesteeLheadlhead and other aquatic habitat.

• Correct existing stream channelchannel instabilities.instabilities . ". • ResRestoretore Codomices Creek channel and riparian corridor as mitigation for thethe loss of existing channelschannels on Village Creek and the Codomices byby-pass-pass channechannel.l.

• AAvoid void causing undue cost to thethe University Village hhousingousing redevelopment budget.

• Miminize project costs to thethe degree feasible.feasible.

• Provide some habitat forfor wildlife and somesome remnant of thethe historic riparianriparian environment. r

'. WaterNaYsWaterways RestorationRestorabon InstituteInstitute 17

AR 007436 DRAFT 3(3/1(/0101 PPhasedhased Creek Improvements

,• Evaluate flooding impacts of the proposed creek resrestorationtoration design on adjacent propertiesproperties..

,• Work with UnionUnion PacificPacific Railroad and CalTrans to increase cculvertulvert capacity downstream.

Waterways Restoration Institute 18

AR 007437 ,.

DRAFT 311101 Phased Creek ImprovementsImprovements

4.0 HYDROLOGY AND STREAM DYNAMICS

4.1 Equilibrium or "Stable""Stable" Channel Conditions

The basis of any design alternative must start with the knowledge required to achieve a stable channel. The restorationrestoration parameters described in this report were calculated to correccorrectt the existing instabilities of the creek aandnd provide a ccreekreek channel that isis moremOTe in balanbalancece with its environment. In this case, the term "slistabletable"" refers to an active, meandering stream channel as you would find in nature. It is in "quasi"quasi equilibrium."equilibrium/' or stable,stable, in the sense that ththee channel width and depth are in balance with the size of the watershed. The discharges and thethe sediment loadload transported by the creek are in balance,balance, and the channel slope and sinuosity are correctly matched with the creek's valley. The proposal strives to achieve design equilibrium SO that over time CodomkesCodomices Creek will not create problems by either excessively eroding or depositing sediment.sediment. A stable creek channel will be more resilient to future adjustments from natural and human

Although watershed conditions can changechange over timetime,, even in this already very denseldenselyy built urban environment, a channel designed with the correct width and depth will help avoid the problem of the creekcreek attacking its banks witithh destabilizingdestabiiizing erosion and/ or the problem of the creek channhannelel filling in and choking with sediment. The channel also needs to have the cocorrectrrect length and sinuosity toto have this desired stabilitystability.. A channel in this quasi-equilibriumquasi-equilibrium is one in whichwhich its sinuositysinuosity and the slope of the bottom of the channel isis matched correctly to the overall slopeslope of the stream valley. Sinuosity refersrefers to howhow long a path thethe" streamstream. travels over a given straight line of the meandering stream whhiichch is called the mmeanderbelt.eanderbelt. ThThee design meanderbelt refers to the width of project area needed to provide for the correct channel slope, sinuosity and width (Figures 4-1 andand 4-2)4-2)..

These project designdesjgn featufeaturesres have beebeenn quantitativelyvely derivedderived and areare described in greater detail in Appendix B, Stable Channel Design Process.

Flood DischargesDisc.harges The Codornices Creek project also takes into considerationconsideration the goal toto reduce flood risks to the new University Village redevelopment pproject.roject. The projectproject described inin this report was designed with the objective to reduce the risk of flood damage from the relatively largelarge andand rare 1 in 100 yeayearr flood. Usually this design objective is tied to flood insuranceinsurance standards.standards.

Additional flood studies will be conducted to evaluate this restoration plan once publiC comment has been incorporatedincorporated iintonto the design.design. The studies will\vill evaluate the

Waterways RestoratRestorationion Institute 19

AR 007438 DRAFT 311/01311101 Phased Creek ImpImprovemerovementsnts ability of the restored creek to convey the 1 in 100 year floOdflood that ranges from 900 cis to 1185 cfs. (Flood Peak Table, Appendix C) Design features such as 1-2 foot high landscaping benns will be added to the BOSS center aarea,rea, between 5th and 6thth Streets and between the 8th Street culvert and the street. The final flood modeling will detemtine the exact height and layout of the landscaping benns.

WatelWaYsWaterways Restoration Institute 20

AR 007439 c.

Meander and Channel Slope Restoration Figure 4-1

Sinuosity = Valley Slope Channel SSlopelope

Valley SlopeSlope ChannelChannel SiolpeSlc)pe

Sinuosity=

Channel Length Distance

SoSouurcrcee:: WaterwaysWaterwa ys Restorat,o"Rest ora! ,o"l IInstnstIItutetute

V'I 21 I.;i AR 007440 Geometry of Meanders Figure 4-2

Axis of bend ,// 1-----L ----t---..,-----1----1

A

Point of inflection or crossoverc.rossover

Convexc.onvex bonkbank LocationLocation of Concave bankbonk point'pOint bar L:L:; Meander length (wave length) A:A:; Amplitude rmrm== Mean radius of Cl.lrvatureCLlrvature

Source:Source: Fluvial Processes In GeomorphologyGeomorphology leopold,l eopold, Miller, WolmanWolman (1956)

22

AR 007441 1, DRAFT 311/01311 (01 Phased Creek Improvemen:s

5.0 PHASED CREEK RESTORA nON PLAN

This section describes the desdesignign basis for the creekcreek enhancement phasing plan. The plaplann assassumesumes that major improvements to most of the reaches can be made as the University pproceedsroceeds with its plans for developing its San Pablo ffrontagerontage in conconjunctionjunction with a private developerdeveloper.. SignificantSignificant workwork on the reachreach between Fifth and SSixthixth Streets cacannotnnot be achieved untiuntill Step 2 of the housing redevelopmentredevelopment prproceedsoceeds.. ThusThus,, the plan is descdescribedribed in two phases wwhichhich can bbee accomplished as additional rright-ight-af-wayaf-way becomes availableavailable.. Phase 1 also assumes that the U.SU.S.. Post Office will cooperate with ththeseese efforts by moving their parking lolott wal1wall 12 feet to ththee souuthth.. ThereThere are nnOO pllansans to move existing commercial builbuildingsd ings on the ,. Berkeley side. The plan does notnot,, of course,course, represent ththee restoration of the historihistoricalcal conditionsconditions of the creek, but' it does represent the appapplicationlication of geomorphicgeomorphic principrinciplesples to rrestestore some of the structustructurre, functions and diversity associated with the historical creek envenvirorunent.irorunent.

The planplan is described in reaches, beginning at the railroad tracks aandnd going east to San Pablo Avenue.A venue. Each of these sections describes the opportunities and constraints, historic and exexistingisting coconditions,nditions, steps to accomplish thethe impimprovrovements,ements, design parametparameters,ers, and stream channel design for that particularparticular reeach,ach.

5.1 Phase One Creek Improvements Railroad Tracks to Fifth Street Reacl.Reac/. OpportunitOpportunitiesies anandd ConsConstratraintsints

The right-of-way is constricconstrictedted at Fifth Street because of the reqequirementsuirements of tthehe playing field dimensions on the south side, the needneed for an access road to the rrelocatedelocated sports fields in A1bany,Albany, and the new UCB housing on the north side.side, The rest of this reachreach pprovrovides a Significant restoration opportunity.orhmity. The inadequatelyinadequately sized and maintained railroad culvert directly west of the CityCity of Berkeley property creates an on-goingon-going backwater conditioncondition and associaassociatedted flooding pproblem.roblem.

HiHistoricalstorical and ExiExistingsting CCoonnditions

HistHistoricalorical maps and drav.ringsdrawings indicate that this channel entered a low gradient marsh environmentenvirorunent (Figure 55-1-1 throughthrough 5-3). A recerecentnt history publication,publication, Berkeley 19019000 (Schwartz 2000), describes the historic environmironmentent in this area as ththee Codomices lagoon. The channel was most likelylikely narrower, deeper and maremOre sinuoussinuous than the channel upstream of FifFilthth Street. The historical channel conditionsconditions were probablprobablyy what are known as a Rosgen E-E-ChannelChannel type given the indications from historic information that the creek flowedfl owed through a wetlands on very flat gradient withwith the channel narrowing and becoming very sinuous below Fifth Street.

WaWaterwaysterways Restoratiionon Institute , 23

I. Wi

AR 007442 DDRAFTRAFT 311101311101 Phased Creek ImprovementsImprovements

Currently the creek in this reach is straightened with portions lined in concrete which is cracking and failing. The creek has been bounded to the west by the railroad tracks since the 1800s18OOs. In recent history (1947 photophoto;; Figure 5-2) the creek was diverted around, into and out of the now demolished steel factory.factory. The ccurrenturrent condition of the creek banks and concrete channelchannel are very ununstable.stable. The area has been HUedHlled over time and the riparian vegetation consists of sparse remnants of mostlymostly willow species.

The origins of the bypass channel invoinvolvedlved creation of a ditch dug priprioror to 1930 to drain andj or irrigate an agricultural field. This bypass channelchannel,, which flows northnorth and joins the lower Village Creek Channel to a culvert under the railroad trackstracks,, continuescontinues to divert some flow from Codomices CreekCreek.. The bypass is an unundesirabledesirable feature for channel stability because it splits flows away from the main channel ofof Codomices CreekCreek.. ThisTIlls in part contributes to the cloggingdogging of the lower Codomices creek channel with sediment because there are not sufficient discharges to transporttransp'rt the sediment load.load. It is also undesirable for migrating steelhead which can follow the Village Creek flows up ttoo this bby-passy-pass channelchannel where thetheyy can become trapped. The culvert at the railroad tracks controls the discharges which can run off this lower section, creating a Significant backwater and pondingponding of flood flows.

Phase 1 Improvements

ThThee steps to the PhaPhasese 1 improvements in this area are:

• Remove Codomices Creek bypassbypass • RelocateRelocate softball field to Dowling Park; reorient the Albany soccer field to north-south direction • Remove concrete culvertculvert at 5th Street and restorerestore channel to natural meander • Relocate fieldhouse facility in Albany ReRelocatelocate fieldhouse facility in Albany • ProProvidevide a vehicvehicular/pedestrianular/ pedestrian access bridge over the creek at 5th Street

Design Parameters

DownstreamDownstream of Fifth Street the channechannell type changes as the creek negotiates a flatter gradient as it transitions towards the Bay's wetlands. The carefully rendered 1964 sketch at Fifth Street indicates that the channechannell changes to a narrower channel in this area. This information corroborates with historic maps and accounts which indicate that the locationlocation of the creek entering a marsh is a low gradient Rosgen E-type channel. These channel types have a much lowerlower width-depth ratio than the upstream channels. TheThe regional graphs used to help guide the design in the upper reaches do not applyapply to this charmelchannel type because there are no known gauge stations onon this stream chchannelannel type in the region. HoweverHowever,, direcdirectlytly 2000 feet ttoo the north. Village Creek is situated in the same gradient and soilssoils.. There, historic photos indicate that before Village Creek was culverted, it entered wetlands in this area

Waterways Restoration IInstitutenstitute 24

AR 007443 r ':;

I " 1865 U.S. Coast Survey Figure 5-1

•

"" , , ,

"

" r

., .-/' ..-/ ' '". • ,\, .. v,," \

,,' "

" , / , : . " ,

2

; u

AR 007444 1947 Aerial Survey Figure 5-2

2626

AR 007445 City of Berkeley Dept. of Engineering Meander Figure 5-3 5th to 6th Streets

27

AR 007446 DRAFT 3111013/1/01 Phased Creek Improvements

with a sinuous (1.6) channel. The Village Creek restoration project was completed in the Fall 1998 with a designdesign sinuosity of 1.6 and a width-depthwidth-depth ratio of 4-54-5.. This rerestorationstoration seems to reasonablyreasonably match this landscape andand is thus far reresultingsulting inin an equilibrium channel. Therefore the channel design parameters used for the channel below Fifth Street are the following:

Channel formingforming oror bankfull didischargescharge - 80 cis Bankfull width --1212 Itft Bankfull depth - 3 It Width/depthWid thl depth ratio-ratio - 4

Stream Channel Design

This entire stretch of the creek is being designed with a 12 foot wide, 3 foot deep channel.channel. The projeprojectct right-ofright-af-way-way up to old Fourth Street enables the rrestorationestoration of a substantial floodplain environment and creek meanderbelt within a 135 foot right­ ofof-way-way.. The design sisinuositynuosity is 1.69. The stream channel right-oE-wayright-of-way is narrowednarrowed between the proposedproposed. new rresidentialesidential buildings to the north and the new soccer field to the southsouth below Fifth Street to a corridor 40-70 feet wide. An average sinuosity of 1..3636 can be attained for the 275-foot reach belowlow Fifth Street. This reach should have an average sinuositysinuosity of about 11.5,.5, but the oveoveralralll averageaverage charmel sinuosity from Fifth toto the Railroad tracks is 1.5..5. The overaloveralll channel length in this area should help prepreventvent future headcuttingheadcutting.. The constrained meander belowbelow Fifth Street will need to be treated with rock buried hvo feet behind the outsideoutside meander bends and the outside bends will need substantial soil bioengineering plant systemssystems. The buried rrockock should not be present on the channel surface.surface. This constrained section will need steeper 2:1 charmelchannel side slopes.slopes.

RemovingRemov ing the Fifth Street culvert and the bypass will have substantial benefits toto the stabilizationstabilization of the creek by enenablingabling a corrected stream channel slope to be constructed. The removal of the splitsplit flows will correct sedimentation problems on the main channechannell and greatly benefit restoration of ssteeteelheadlhead and other aquatic fauna.fauna . Fifth to Sixth Streets Reach Opportunities and ConstraintsConstramts

This reach is the most problematic becausebecause of the existingexisting housing on the north side of the creek, and the commercial buildings on the south side that are close to the topop of the bank. Any "restoration" in the short-term will be limited by the existing 1960's1%0'5 uunitsnits on the north bank. There should be an opportunity fforor SignificSignificantant

Waterways RestorationRestoratioo Institute 28

AR 007447 CCRAFTRAFT 311/01311101 PhasedPhased Creek Improvements

improvements in the futurefuhtre when the university undertakes Step 2 of its housing redevelopment program.

Historic and Existing Conditions

The historic records (Figure 5-3) indicateindicate that the creek used to meander under the Ehret Plumbing Building and parking lot to the south as late as the 1960s.1960s. The sinuosity was a valvalueue of 11.3.3 (the channel meandered a distance of 130 feet every 110000 feet). The creek was straightened in 1994 and a culvert put in at Fifth Street. I , Surveurveysys of existing conditions indicate that the Fifth Street culvert was likely i iinstallednstalled well below the natural grade of the creek. This has resulted in a chronic I' maintenance problem iinn which the culvert and channel fill with sediment,sediment, thereby impediimpedingng the passage of flood£I00d flows£lows. Flood flows£lows over the Fifth Street culvert are c(o'mmonmmOn.

A restoration project completed by the City of BerkeleyBerkeley in 11996-97996-97 significantlysignificantly increased the channel capacity in this reach. Efforts to achieve the historic channelchannel sinuosity fell short of the design goal of 1.27-1.3..27-1.3. AttempAttemptsts to direct more flow away from the bypass culvert have been frustrated byby the chronic sediment deposition at the Fifth Street culvert which creates a backwaterbackwater co ndition and encourages flowflow into the deeper pass. To date there is evidence of headcutting due to the inability to achieve the adequate channel length (Figure 5-4).

The 1996-1997 projec~s design bankfull width of 16 feet and bankfull depth of 1.5-2 feetfee t near the Sixth Street culvert appear to be aiding channel stability above the area influenced by the byy-p-passass and Fifth Street culculvertvert (Figure 5-5).

Phase 1 IImprmprovementsovements

• Restore 200 feet of stream channel • Remove by-pass and plug remaining section • Realign channelchannel away from structure on south bank

ThThee bbyy-pa-passss culvert and headwall can be reremovedmoved and the remaining section of thethe undergroundunderground by-p-passass plugged. Two hundred feetfeet ofof channelchannel can be restored in this area linking to the restoration channel downstream and the existing channel contrained by Ehret Plumbing on the south bank and the 19601960's's university houhOUSingsing on the north bank. WhenWhen the 1960's1960's university hOUSinghousing requires replacemenreplacement,t, Phase 2 of the restoration projectproject will be aableble to complecomplette thethe channel mmodificationsodifications upup to 6th Street.

The 6th StreetStreet culvert wowoulduld remain during Phase 1, lleeavingaving the channel subsubjectject to 6- 7 feet per second vvelocitieselocities in a llargearge stonnstorm.. Soil bioenbioengineeringgineering systems can

WaterwaysWate!WaYs Restoration Institute 29

AR 007448 r i Headcutting Figure 5-4

KNICK POINT

...... ~~_ __ KNICK'pOINT ---- PROROGRESSIONGRESSION

...... "'~-:~f-- -, KNICKKNICK PQINTPOINT 'PROGRESSIOPROGRESSIONN --- --,-,-, --- ..•. \,

Source : Waterways Restoration Institu te frO

30

AR 007449 • ~ ~ o , ~ U1 U1 tD tD C -I g S- UI ...... ::T ;0 ...... :!1 '" !a !! ~ ~ U1 U1 OJ OJ OJ Co >< Co Q. Q. o o :::I :::I :::I 11\ .... 11\ UI UI n 11\ .... o III III n :s :s :s m to IC to IC , _ e vert Lin Line ul Culvert C . t .. nter ree t ~ \ Ce S Street h h ••• t t 5 \' ~~ • ting • .. m 5 m xis ltaot fro from ,. Existing n'" : E eam c~ Coo"lta" \: Street Street ... tr g .. s n th n- 5 5 Culvert t : ~ ~ . Plaomoo Planm . dow down-stream ee . c. F Feet e .. ing rt,m o .... 200 ook looking l . Mo",mec. '. . • e " M " "o ... View View . he t B: Ka Kathe Channel 00 100 1 o" •...... • Phot Photo" l •.••...... •..•...... • t I .•. .. Existing ee r keley c of ~ st street 0 0 Be Beckeley/ th 4 4th . UC UC ~~ ~ d C. ol old s r Gl GI5C. ' ..••... Centerline nea near ce .. . 100 o", ...... ••... . 50""e' S eam •• .. tr ••• ... . . down-s down-stream •••••• .... Culvert Culvert . g •• n .. i •• . ~ ~ • ook looking l 110 I\,oad ~ • • • ~ R~i\rc,ad ~ ew i View : V : A @ @ _ _ ~ '"

AR 007450 DRAFT 313111011101 PhasedPhased Creek. ImpImprovementsrovements perform well underunder these velocities. This is rrececommendedommended as a long-telong·termrm channel condition because the channel length will still a110w some headcuttingheadcutting and the Sixth Street culvertculvert willwill createcreate some backwater conditions on the 6th to 7th Street reacreachh upstream. The Phase 1 channel hashas a sinuosity of 1.14 and should have a channel lelengthngth of 1.31.3 iinn this reach.reach. CChannelhannel widthth wiwillll continue the 16-foot16--foot widwidtthh used in the 1996 project. The outside bends will reqequireuire rock and vegetation rereinforcement.inforcement. The channhanneell alignment can be pulled away somewhat from the sosoututhh bank commecommercialrcial buildings with the removal of the 5th Street culvertculvert,, providingproviding some south bank stability benefits (Figures 5-6 and 5-7).

Sixth toto EighthEighth StreetsStreets ReachReach Opportuniititieses anandd Constraints

The goal is to provide sufficiensufficientt right-ofright.of·-way ttoo allow for a ·natural meander plus bike/pedestrianbike/ pedestrian trail on thethe sosouthuth side of the creek. Attaining this goal is dependent on rrelelocatingocating facilities (the groundSgrounds maintenance facility, a storraagege shed used by the AAlbanylbany Oilldren's Center, and a portiportionon of the AlbanyAlbany Children's Center play yard) as ppaart of the commecommercircialal developmendevelopment portionportion of the ppropertyroperty fronting onon San PabloPablo AvenAvenue.ue. There are as yet no pllaansns foforr relocating the Albany Children's Center,Center, so this buildingbuilding and its needsneeds (orfor outdoor play space will remain as a given constraint. The U.SU.S.. Post Office may be a project participant with tthehe possibipOSSibilitylity of moving its paparrking lot wawaHH toto the southsouth to allallowow for the needed flood damadamagege redureductionction benefits of the floodway alalongong the creek corridor.

HistoriH istoricc and Existing Conditions

This reach of creek hashas been straightenedstraightened and filled. ItIt exhibits bank failurree along tthehe entire reareachch and there is evidence of SSignifignificant channel incisiincision.on. In order to pproviderovide sufficient channel slope to matcmatchh the valley slope and achieve the historicahistoricall, stablestable 11.3.3 sSinuosityinuosity,, the channel slope sshoulhouldd be steepenedeepened sommee.. TThehe SixSixthth SStreetcreet culvertculvert creates a back wattereringing of flood flowflowss and also hindershinders achieving thethe correct slope for thethe cr""crC"C J... bottom because it is too lowlow..

Between whernl'' s..·\s.." ·ententh StreeStreett would be logically located and EighthEighth Street, the channel ha~ tx'l..'nht'\'n hned wiwitthh sackcrete on the north bank (Figure 5-8)5--8).. A concreteconcrete apron extend!'extend!' "'rlilT Jrrroxima

Waterways Restoration Institute 32

AR 007451 'T, '

Channel Design: RR Tracks to 5thth Street Figure 5-6 Plan and Profile: Phase 1

, • . ,• -"w~ -w. . .- -. 0~ , 0z 0" -w .~ .; > "",",~ - ,-• .u.' , - I"~ / "'I ~ \ \ ."'t·" , '\ '" ,''J ~ \ ,,-t ~ SI( \ K"'~' , ~ I :, , " " t .---" -" •0z I ~ I, ,•> u• i . • -z,0 ,

0 0 .._ 0N '"'ii :;: u:0:• 02"(OZ"I ,'l' .l ,".. ,. ,

, :o! i~ .0.o." .'0'o r i ;;; t! ""oz u ;;;;: 8.. I uw ;t;: III:!! ..cC I c­" 0z • o.. .. ·- ~ .c ,I 0;• ;; u • , ~ 0• ,i • • u ":>'"::> u sz· i3'"G '~6" V • r ! ,~ -',' ,jl.l\ 33]]

AR 007452 1 Channel Design RR Tracks to 5th Street Figure 5-7 Cross Sections: Phase 1

-... _. SourceSource:: WaterwaWaterwaysys Restoration Institute

,

SourceSource:: Waterways RestoRestorationration Institute

3434

AR 007453 ~ c:::! - ' ' ... - . ~ ~ S' ~ ~ S' o o \II /I) "T1 "T1 0 0 o o ..... ::J ::J III ...... III - ... \II /I) ~ \II til Co C 0 o -' U1 ::J III iil ;:;: iil a ...... , m m CO 0> )( ::J III n ... IC IC IC ' ' . . . . ' ,,' . Line Line ... r .. . . ' .. . , .' Cente Center .. . . Street Street th sting sting i i 6th 6 x E Ex .. ... from from . . , .... :" :" ...... ' . .. stream .. up upstream ng Feet looking looki 200 View View : : 0 D 100 t eet eet Consultnnt Consuilllll . . r r 0 .. St St h t th nuiling nnning l l 6 6 ' ' ...... I l .. om .. imcr, ...... from fr . . _ MOI1 MOI1illlcr, .. 00 . . ... Katherine KatllCrlne ; : os os l l downstream downstream o I'h I II'hu ing ~ lc), oking look lo Ilclkc Berkeley uc UC , View View : : c c GISC GISe, : : CIJ Source Source ~ ~

AR 007454 Rosgen Channel Type Classification Figure 5-9

LONGITUDINALLONGITUDINAL,, CROSS-SECTIONAL AND PLAN VIEWSVIEWS of MAJOR STREAMT REAM TYPESTYPES

CFtOSS­CI'tOSS­ SECllOKSECTION

Source:Source: (1994)

36

AR 007455 DRAFT 311101311(01 Phased Creek Improvements

Phase 1 Improvements

., The steps to improving this reach include: , • Rel9CateRelQCate the two Little League fields to Dowling Park (north) • Culvert the section of Village Creek adjacent to Dowling Park • Relocate the grounds storage building in Albany adjacent to the creek to the I San Pablo Avenue frontage commercial development • Relocate portion of Albany ChiChildren'sldren's Center play yard and a storage building • Restore Codornices Creek between Sixth and Eighth Streets I, ,. ," • Move US Postal Service wall 12 feet to the south I • Construct a bicycle/pedestrian trail on the south side of the creek I, Design Parameters , The channel valley is flat and the channel historically had a well developed sinuosity starting from the Fifth Street bridge up to the Ninth Street area. The sinuosity averaged about 1.3.1.3. These sllopesopes and plan fonnsforms suggest a Rosgen C type i channel. Therefore the channel design parameters used for the channecharmell between 5th " and 8th streets are (Figure 4.3: C type channel):

Channel forming or bankfull dischargedischarge - 8060 cis Bankfull channel width -1- 166 ft Bankfull channel depth -1.5-1,5 ft Width - depth ratio of - 10.6 , , i Stream Channel DesignDesi~ III I The Phase 1 project will be constrained by the Sixth Street culvert. Other existing land use constraints include the new university housing located betweenbetv.reen Sixth Street I, and theoretical Seventh Street. The plan requires setting back the 205 feet of , chainlink fence and 325 foot long wall between Sixth to Seventh Street on the U.s. Post Office property 12 feet in order to realize the required floodplain space, channel length and trail.

Many difficult channel stability problems have been made much llessess criticalcritical by the rearrangement of the proposed site plan by the university on the north bank of the creek. The creek bank near the Albany Children's CenteCenterr play area will be in a safer placement in reference to the flows discharging from the Eighth Street culvert. Ideally the u.s,u.s. Post Office Wall (325 lineal feet) should be moved south 12 feet to complete the project right-of-way needs forfor flood space, bank stability and trail. Approximately 22 perpendicularperpendicular parking spaces would be affected by moving this wall. 1hisThis loss of parking could be reducedreduced to 13 to14 spaces by ssubstitutingubstituting 8 or 9 parallel spaces along the relocated wall. (Existing parking spaces are assumedassumed. to be

Waterways Restoration IInstitutenstitute 37

AR 007456 DRAFT 311101311101 PPhasehasedd Crreeeekk Improvements

20 feet by 9 feet and ththee replacemeneplacement spaces wouldwould be 8 feet by 22 or 24 feet)feet).. The reach will continue the 2:12:1 channelcharmel slopespes upup to the trail. IInn tthhee event thaatt the post ofofficefice wall cannotcannot be moved, the channel will require redesigning fr om thethe beginning of the wall near wherewhere 7th7m SStreettreet would meet the creek,creek, up ttoo 8mth Street.

This reportreport recommends leaving the EighthEighth Street cuculvertlvert inin to create a backwatebackwaterr in ththee deeper upstreamupstream channelcharmel during large flood flows. The desirdesireded 11..3 channel sinuosity can be attttaainedined in the Seventh to Eighth Street reachreach with the culvert in under this land use scenario (5-1 0 to 5-]5-11 1)).. The lower Codornices Creek designdesign team finds that it is desirable, fforor the managementmanagement of flood flows through tthishis reach and the entirntiree project area,area, toto replacereplace undersizedundersized cuculvertslverts under ththee IInterstanterstatete 80 and the frontage road to the easeastt of the freewayfreeway ttoo correctcorrect for the backing up of fl oodwaterter.. Corrections such as thithiss in the lowerower watershed will enableenable the eventuaeventual removalremoval of the 8th Street culvert.

Eighth to Ninth Streets ReachReach HistoricHistoric aandnd Existing Conditions

1hisThis reach used to be contained in a llargearge concreteconcrete culvert within a rail right of way until 1993, when ththee culvert was broken open andand the creek daylighteddayJighted.. This rreacheach is contained by a rremnemnant of thethe oldold culvert on the southsouth bank and planted rubbrubblele Iiprrfpraapp on the northnorth bank. The stream cchannehannell gradient is not matched toto ititss historichistoric sinuosity and valley slopeslope, and therefore is not stable. Given the constrainttss caused by recent improvements, inincludingduding construction of thethe nnorthorth side trail and park,park, it is difficult to correct forfor thethe factfact the currencurrentt stream cchannelhannel is tootoo short.short. The condiconditionstions forfor this reacreachh were furthfurtherer complicated by the locaocationtion of a gas linlinee at the currentcurrent channel invert downstream of Ninth Street, but this line has since been deacdeactivated.tivated. The widening of the bankfull width ttoo 15 feetfeet inin 1996 hhas,as, however,however, helped contribute to a mmoreore stable channel (Figurree 5-1122))

Phase 1 ImprImprovmentsovments

• Widen and improve existing pathwapathwayy on north sideside of ccreekreek toto accommodate both bicycles and pedestrians. • No stream channel improveovemenments requirireed.d. • Create landscapelandscape benn to reduce overbank flooding at 8th StreeStreett

Stream ChannelChannel Design

The existingexisting channelchannel conditionsconditions wwillill preprevailvail between Eighth and Ninth streets. This reachreach has an uunusualnusual hihiststoryory involvinginvoLving a greagreatt deal of citizen involvement to remove the creek from a culvertculvert. The creek is still constrained for a section on the south bank againstagainst a four toto fivefi ve foot high wall composcomposeded of an oldold side of culvlvert,ert, whichhich the citizen groups did not have the rresourcesesources to move.move. TheThe univerSityuniversity developed an

Waterways RestoraRestorationtion Institute 38

AR 007457 -\ ------. th9' 9' , _. \II til til 'TI ...... \11 til til til C 0 or o '" - ::I .. ... Channel Design: 5 to 7 th Streets Figure 5-10\11 10 _·10 til OJ '" 'tI ... ::r .. 1;"::1 o -::r ..... 'tiC 'tin ::I ::I 0.- ::I .. .. Plan.... and Profile: Phase 1 .

'. J J --~l -< NNE

J . < -~ - w , ••U 94SE , .,I « u L CH""'tlEl J ~• -DHllsE iii r- JI o ,"' 1ice I Of " I ·•l2100 Phase Post Line - Phase Pl''''' Center ---- . Channel, Plane . Creek S lope. S ' .. Ell One TroillRoad Creek Bank Existilg Flood •11100 l . ;i '.' NV[TlT SOrFlIIUEV " _ W~; o Phase , . , I . .' i i I " 0"1o ::u ' j ~u :;l~ .- .

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- IH "0 H UC "I''''', tiilllEt 3·0. 1 5Jl£!J.~ INVERT CUlV[Rf! nH I 't .,,/ .1", ~ GISC, 1'- I' - ~~ - -' o. 7' A - '---1-< I v I r L:=::::==x=1=::::::: \= jec:/::::,:\:::;: ,: ':":' :":J~Source: ~ 39 ~

AR 007458 th Channel Design 5 to 7th7 th Streets _ Figure 5-11 Cross Sections: Phase I

SECION C-e'C-C'

• -~

~nC I'IweIPhase I • SECTION 0-0'

..,

SECTION E-EE-E''

- Source: WaterwaysWa terways RestorationRestoration Institute 40

AR 007459 . . :r :r .. .. I ""' "" .., _. /1) ... "TI "T1 C U1 /1) /1) r1' r1' r1' :::J :::J ...... 1/1 .., _. _. \D r1' m >< l!l. (J) C. 0 0 0 o o o :::J 1/1 ...... 1/1 - - n -. loCI IC loCI IC . • • . . . . Line Line Center Center Street Existing Existing th 8 ...... ' • :", :' " " , from ' . Feet upstream 200 looking ...... •..•.. View F: :r .. ~ .... ID ID ...... ~ ; 00 lQ III 100 Consultant Consultant Planning Planning o Street th 8 - . .. Mortimer, Mortimer, -----~ L '- .>'~ ...... _f from --- ....••.•.. ;.;.;;'~;~~:,/ ,..-- -:_.,~, ~ ' Katherine Katherine . .ut: ,- 100 : ~,._.t~ ---- """ Photos: Photos ---~ downstream ..... / ."." ------... looking . Berkeley ~ . . . UC View . . . . . E: GISC, .' . 00 Source: .... ~

AR 007460 CRAFT 3/1/01311101 PhaPhasedsed Creek Improvements

attractive fenced. trail and these considerable and wellwell-intentioned-intentioned efforts shoulshouldd not be undone at this time.time. Trail improvement shoushouldld not impact the integrity of the existing conditions (Figures 5-13 and 5-14).

Ni"thNinth Street to San Pablo AvenueAve""e RReachead, Opportunities and ConsConstraintstraints

The creek along this reach can be restored within an expanded right-oi-wayright-oC-way that will be available when the 1940s housing is demolished. The bike path connecting San Pablo A venvenueue to the creek can be acaccommodatedcorrunodated in additionaadditionall creek right-of-way or through the conunercialcommercial development area. This will be dedeterminedtermined as thethe conunercialcommercial development is designed and approved. Locating the bike trail along the creekcreek would provide an added creek erosion-flood buffer zone and provide for user safety by avoiding car traffic areas.

Historic and Existing Conditions

A meandermeander bend at Ninth Street continues toto expand ttoo ththee south, indicating thethe need for more width to accoacconunodatemmodate a slightly longerlonger channel at this ssite.ite. The cross­ sectional area was restored in 1997 to a more stable shape.shape. There is nice floodplain

development in thisthis reach. The channel becomes constrained by concrete, debris and walls through the upstream reaches (Figure 55-15).-15).

The reach from 10th Street ttoo San PPabloablo Avenue was straighstraightenedtened and is trytryinging toto flatten its grade thrthroughough headcutting and attacking its banks. The extent of headcuttingheadcutting is illustrated by the four-foot drop &omttom the San Pablo AAvenue venue culvert to ththee now incised creek bottom. Historically this upper channel and the Ninth ttoo TenTenthth Street reach had a ssteeperteeper sloped channel type with a lowerlower sinuosity (about 11.2).2) than the channel downstream (abo(aboutut 11.3)..3). ThThee Ninth Street to San Pablo AvenueAvenue reachesreaches fit the description of a Rosgen B type channel (Figure 5-9).5-9). .

Phase 1 ImprImprovementsovements

Steps toto improving this reach include:include:

• Relocate ththee Little LLeagueeague fieldsHe1ds • Remove existing student housing units along San Pablo AvenAvenueue as part of conunercialcommercial development (lease)(lease) • Restore Codomices Creek from San Pablo A venue to Tenth Street • Remove 1100th Street culvert • Provide access ttoo tthehe bikebike/pedestrian/ pedestrian path from£rom San Pablo AvenueAvenue eithereither along the creek oror via thethe new commercial devedevelopmentlopment (depending on safest and mmostost appappropriateropriate route from San Pablo Avenue)

Waterways Restoration Institute 42

AR 007461 ::r ;. .. ::r ; I _. ~ C ID ." ~ ., ., W ..... iii' 0 0 (I) U1 .... ID ID !!!. ID ID III .... III -. .. u::I u::I _. ,,~ ~ ~ III ... ~ ~ ii'~ iD~ CI.,- o e. ID\C) ,,0 11\ -::T III:J III III .. ::r ., " :' "n : : ~ ~ 1 ~ '!' :; ~ .; ~ - "" "" 0 on "? ... IN n 0'" 00 30 3000 ~ ii: !!l ,~-- I 00 I 2'* .. Phase Line Phase ! I j I I , Center Channel, Plane Creek Slope, 00 00 One Bark Existing Rood Qeek TraillRoad 2. ,. 00 >0 , .: VERT Phase Ul 0«. EET ~«. LEV LEY c, " IT IT BOX NylH' Cl) 26.15 SDFF SOFF ICHTH"ST leH ~O '"'<"' 100 27 ,7 - . .' . ... - r / r / -~ ~- ~- +~ le" .; N <0'" ON ';:N Feet .0 . _ - N, ~ 26 0 ... ,. NO ~O ~ ~. ~ '1';; 'l';; N ~ on 'f .0'" \ ~ 100 EL~~ EL~~ El=21.~ El=21.~ 25.00 25.00 IT IT RT RT ..J ..J I~ 1.---7 ' . . SOF INY Site WRI STIIIIQ-- CRETE and o CO EX Office - Post Berkeley \ 1 \ UC /C 100 o? .. GISC, I ..ro. ~ NEl NEl 0 0 0 40 >0 20 Source: Source......

AR 007462 thth Channel Design 7th7 th to 9 Streets FigureFigure 5-14 Cross Sections: Phase 1

SECTION F-F'

,-""0.-0

SECTION G-G'

- .... ~ -- --,,"..-_,,-,,-...... -

• ,

Source: Waterw Waterwaysys RestoratRestoration Institutete

4444

AR 007463 -­ ------'-- . . - 9' o o "CI _. \II ~ \II \II t1> t1> t1> t1> >< or or C­ C­ O O C "II n> n> n> C n> C n> o o c m m ::I ::I iil ... III III III ...... :I :I ...... , .. ." _. _. .. ., ~ \II ~ III .. o C. o -. 1/1 -. ::I ::I ::I - n n - II) ...... III :I 10 :I :I ...... _. IC - .c' IC IC ------line - - -._ ---- . - . Street " - h h t t Center - - 10 - - _ ". -" from Existing - .- .... .' \ ' . ... .' downstream - ~ H • .. ® Feet . .... looking ..- 200 ._ ._---- ••• View View __ -_ .' . _. ~­ H: - - .. .. ------100 100 ---_ --- \ - . \ -' ----=------=----- reet - , t O ------Street S o Str-ee-r th th 9 •...... ••• 10" - b:=J from ------"------~ 100 :." • . . . • • downstream ...... kelev r looking Be Berkelev '. . uc uc . View : G GISC. GISC, : ({; Source Source: .. .. ~

AR 007464 DRAFT 3/1/01311101 Phased CreCreekek Improvemmprovementsents

Design Parameters

Above NintNinthh Street where the valley slopeslope gets closer to 2% and the historichistoric sinuosity appears to average near 1.2,1.2, it is assumed the cchannelhannel may have had a more confined floodplain more like a Rosgen B type cchannel.hannel. The cchannelhannel boundboundaryary conditionsconditions are greatlygreatly influencedinfluenced by the very cohesive, heavy clays. BasedBased on past project expeexperiencerience aatt NinNinthth toto Eighth Streets, it is assumassumeded that the channel can achieveachieve a significant level of stability if the channel lengthslengths and sinuouositysity as well\vell as the width anandd depth areare correct. The design parameters thereforetherefore selected for thethe active channel between NinthNinth Street and San PabPablolo Avenue are asas follows (Figure 5-9: B type channel):channel):

ChannelChannel forming oorr bankfull didischargescharge - 80 cis Bankfull channel width - 15 Itft Bankfull chanchanelel depth - 1.5 Itft Width - depth ratio of -10.6

Stream CChannelhannel DesignDesign

ThisThis reach can attain thethe restoestorationration parameters identified iinn the firstfirst section of this chapterter.. TheThe creek willwill be regraded with ththee more sstabletable width of 15 feet witwithh a 1..22 sinuosity. The side slopes from the floodplain trail can vary from 3:1 toto 2:11,, thereby makinmakingg it a safe environment forfor a trail. Bank stabilitabilizationzation wiwillll be able to be attained withwith basic soisoill bioengineeringbioengineering planting systems such as willowwillow and cottonwoodcottonwood stakesstakes and posts and brush layering (Figures 5-165·16 and 5-17)5·17).

5.2 Phase Two Creek Improvements

Fifth to SixtSixthlz Streets ReadzReac/l OpportunitiesOpportunities and Constraints

TheTherere shouldhould be an opopportunityportunity for significsignificanantt impimprovementsrovements to thisthis reach in thethe future when thethe university undertakes Step 2 of its housing redevelopmentredevelopment programprogram However, the modified right-of.wayright-of-way will result in the loss of 9 units ttoo the cunentcurrent designdesign forfo r SSteptep 2 of the University housing so the plan would have to be revised if this unitunit loslosss is to be avoided. TToo link thethe Phase 2 channel from the locationlocation of the 6th Street cuculverlvertt toto the PhaPhasese 1I, 6th to 8th sstreetstreets channelchannel, 75 feet of restored channel will be added.

WatWalerwayserways RestRestorationoration InstituteInstiMe 46

AR 007465 .\I' .! r •, Channel Design: 9th Street to San Pablo Avenue., Figure 5-16 o Plan and Profile: Phase 1 , 0 "

,!'0' . ,

!I I Ii San Pablo Avenue • • • ! l o '" ,,'I , : v ; , ~'~~--~(T-) -+--~--~~ ~~~>~~~<> (--~--~--~~ " .. \ z~.c_ - \ • ~ i 7 .; ( " , - I, ---+~:~_~~'-' --~~' --+----1~ \ ~ ~ It •, T \ j

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0 ' , '. ! 47 :,:1;f, '" AR 007466 Channel Design 9th Street to San Pablo Avenue FigureFigure 5-175- 17 Cross Sections:Sections: Phase 1

SECTION H-H'

-~- , - SectionH

SECTION 1-1'I-I'

• -~ , ""'"'""""' I Source: Waterways Restoration Institute

4488

AR 007467 :I I I DRAFT 311101 Phased Creek lmproveImprovemertsmerts

Phase 2 Improvements

Based on such a redesign, the steps to improve this reach would be:

• Remove 9 units of University Village housinghOUSing and two parking spaces along Codomices Creek bet\tVeenbet",.. een Fifth and Sixth Streets • Remove the Sixth Street culvert and replace with bicycle/pedestrianbicycle/ pedestrian bridge • Increase meanders in the larger rightright-ai-way-ai-way available for creek improvements. • Construct a floodplain footpath • Add 75 feet of channelchannel at the 6th Street culvert area to link to the PPhasehase 1, 6th to 8th streets channel.

Design Parameters

Design parameters for this reach are the same as those used forfor the 6th to 8th streets I I reach. TheTheyy areare:: ~ t Channel forming or bankfull discharge - 80 cfs Bankfull channel wwidthidth -16 ft BankfuBankfullll channel depth - 1.5 ft

" Widthdth - depth ratio of -10-10.6.6

Stream CharmelCharmel Design ,~ . The channel reach extending to below Fifth Street isis vulnerable to bank over~topping and erosion because of the increase of flood flows which are released to the downstream reachesreaches by the new development creek project.project. The Phase 2 improvements will incincreaserease the channel stability both up- and downstream fromfrom Ii I this reach. CompCompututer modeling of the Creek with Phase 2 improvements in place,place, I with the Eighth Street culvertcuI vert remaining, and with the use of soil bioengineering !,i , vegetated methods of stream bank stabilization, shows that high velocities can be , ' restricrestrictedted to undunderer 6 ft. per second in this reach. The creek right-of-wayright-of~way between :1 Fifth and Sixth Streets affordedafforded by the Phase 2 plan can also concontaintain thethe 1 in 100 year flood discharges of 600 cis if a 1 -2~2 foot landscaping berm located on the terrace (ground(ground elevation) is integrated into ththee landscaping plan between the housinghOUSing and II. the creecreek. The sinsinuosityuosity of the Phase 1 interim channel can be increased in Phase 2 I , to the desirable 1.3 designdesign parametersparameters and the correct channel width of 1166 feet can be i aattained.ttained. Side slopes on the north bank can be vaiiedvaried from 2:1 to 3:1, makingmaking the . creek corridor safer for the hhousingousing area on the north bank. A s ix~foot wide pedestrian trial is beingbeing pprrOVidedOVided along the floodfloodplainplain to link 6th Street and the il regional trail with ththee athletic fields below 5th Street. A pedestrianpedestrian can continue I. i WatWaterwayserways Restoration IInnstitutestitute 49 I AR 007468 DRARAFTFT 3'113{1101 Phased Creek Improvements from 5th Street along the planned 5th Street access road and access another pedestrian trail continuing ddownown the north side of the creek.

A few project features need to be integrated into this plan to avoid flood damages from the 1 in 100 year flood (600 ciscfs scenario). If tthehe Eighth Street culvert is left in under the current conditions, flood flows will\vill continue to overtop the EighthEighth Street culvert. The recrecorrunendedommended design is to regrade the trail and landscaped area immediatelyimmediately adadjacentjacent to the upstrupstreameam entrance of the Eighth Street culvert to allow for a greater backwater condition upstream of Eighth Street. (Figures 5-18 and 5-19).

Waterways RestorationRestora tion Institute 50so

AR 007469 th Channel Design: 5 to 7th Streets _ Figure 5-18 Plan and Profile: Phase 2

,

, -" :;l~ ,~ « III , or « j ,i f [I, '--- , I , • ~ , , - , • ,8 I •"

- , 0"O'rL1 !):j th 6 Street~Street ~ I 3S'IHd3S'IHd "C\ " /

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AR 007470 th Channel Design 5 to 7th Streets Figure 5-19 Cross SectionsSections:: Phase 2

SECTION C-C'

SECTION 0-0'0-0'

'" SECTION E-E'

, SecnonSrcnon E PIwoIPI..e DII Source: Waterways RRestoraestorationtion InstituteInstitute 52

AR 007471 DRAFT 311101 Phased Creek Improvements

6.0 RIPARlANRIPARIAN CORRIDOR DESIGN

Lower Codomices Creek is located in an ecotone (ecological transitional zone) between several major vegetation communities.communities. To the north is the North Oak Woodland, to the south is the Southern Oak Woodland, to the west is the (historic) Coastal Marsh and to the east are Oak Savannah,SavaI111ah. Chaparral and Redwood communities.communities. The lower Codornices Creek riparian corridor was comprised of plant species from allaU of these plant communities and was dependent on microdimatesmicroclimates caused by variation in elevation, aspect, and canopy tree shade conditions. Dominant plant species included Salix sr.,sp., Alnus rogosa, Quercus agrifolia, and Acer mo.crophylium.mtlcrophylium.

The project reach is located within the cohesive, alluvial soils of the lower watershed. The topography is flat with broad floodplainS. Channel inverts depths rarely exceed five feet below the channel top of bank and well-defined terraces are not evident. The area below Fifth Street was historical1yhistorically a salt marsh that has been separated from tidal interaction due to the construction of the Southern Pacific Railroad and 1-80I-SO freeway.

Currently there are few existing native species along the channel, with the exception of two reaches where restoration efforts have preViously taken place. On the north bank between the SPRR and 5th Street there are two small clusters of willow. There are no existing native species on the south bank. The channel reach between 5th Street and 6th Street was the subject of restoration efforts in 1998. The native vegetation planted in this reach is immature and portions have been removed due to maintenance activities by the university and streamside residents. Between 6th and 8th streestreetsts are two willow trees on the south bank and one on the north bankbank.. Management activities in recent years have removed much of the herbaceous vegetation in this reach. The reach between 8th and 9th streets has been the subject of a sustained volunteervolunteer restoration effort since 1995. A large variety of native tree and under-storyunder.story species are now established in this reach although they are still mature or the trees are now forming a canopy along this reach and pruning is done·' by Urban Creeks Council supervised volunteers.volunteers. At Ninth Street a large willow tree is located on the north bank and provides significant shade to the channel. Between 9th and 10th streets the channel is well shaded with nnon-nativeon-native elms.elms. Little under­ story vegetation exists in this reach. ImmediatelyImmediately above 10th Street there is a large mature willow on the south bank. The remainder of the reach contains only one additional willow and one box elder,elder, both of which are on the south bank. ThroughoutThroughout the entire project reach there are

RecomRecommendedmended Vegetation Restoration Objectives

• Remove invasive plant species.

Waterwayswaterways Restoration InstInstituteitute '53

AR 007472 DDRAFTRAFT 3/1/01 Phased Creek Improvements

• Retain elm tree standstand and manage forfor successiosuccessionn to native species.

• EstablishEstabHsh natinativeve riparian canopy shade trees along north and southsouth banks.banks.

• Maximize diverdiversitysity of native species.

• Manage for diversity of plantplant species age.

• Grade banks and floodplainfl oodplain to prpromoteomote variations in slopeslope and aspect for species diversdiversity.ity.

• MaximizeMaximize use of soil bibioengineeringoengineering systems for bank stabilization and re­re­ vegetation of floodplainfl oodplain andand bbanksanks..

• IncorporateIncorporate locallocal University Village, Albany and BerkeleyBerkeley residentsresidents in volunteervolunteer in-fill plantingplanting projects.

RecommeRecommendednded Species

The recommendedrecommended plant listlist identifies 50 nativnativee specspeciesies appropriate for the Codomices Creek riparianriparian corridocorridor.r. This lislistt hhasas been divided into trees, shrubs, andand groundcoversgroundcovers. Modification to the list maymay be requiredrequired because manymany of these species are not typically availableavailable at most plantplant nunurseriesrseries.. Since the under-story plantingplanting should be conductedconducted over a period of several years,years, contract growinggrowing is a viable option.option. There are a numbernumber of optionsoptions for contractcontract growinggrowing in the Bay Area.,Area, includingincluding the California ConservationConservation CorpsCorps and the locallocal chapter of the California Native Plant Society. (fable(Table 6-1)6-1 )

Installation

A detailed plantingplanting plan shouldshould notnot be developed until final grading plans hahaveve beenbeen cocompletedmpleted iinn order to ensure pproperroper placement of species withwith appropappropriateriate topographic and aspect conditiof!Sconditio~ . Plantings sshouldhould also be conductedcond ucted with a phased approach so that the canopycanopy trees havehave time toto mature and developdevelop the microdimates necessary for some of the shrubs and groundcovers.

Phase I (Years 1 and 2)

ImmediatelyImmediately after construction, 100% Coir©Coir@ erosion controlcontrol fabrics made of erosion resistant coconut fiber should be installed alongalong the active channel to minimize soil loss.loss. In midmid-late-late fall soil bioengineering systems including willow and cottonwood post,post, brushbrush layering, andand stakingstaking of dogwooddogwood and ninebark shouldshould be incorporatedincorporated. into the Coir fabricfabric along the active channel banks.banks. Container planting of the canopy tree species and sun toleranttolerant shrubs shouJdshould also be conductedconducted at this time.

Waterways RestoratRestorationion Institute 54

AR 007473 TABLETABLE6- 6- 11 RESTORATION PPLANTLANT SPSPECECIESIES

Scientific NameJ\ame CommoCommonnNamc Name Zoo, PropogationPropagation Aspect NO(, T,,,,,,T,... """ Acer macrophyllummacropbyll um BigBig LeafLeaf MapleMaple DB,,C Container All , Aesculus californica California BBuuckeyeckeye DB,,C Container All •, Alnus rubrarubra Red Allder A Container NA •1I,.,' Alnus rhombirhombifolia fo lia WhileWhite AlderAkier A Containerntainer NA 1I,.' Populus fremont iiii Fremont Cottonwood A CuttingCutting NA 2,.' Quercus agrifoliaagrifoli.a. Coast Live Oak DB,,C ContainerCoruiner All , SaSalixlix laevigatalaevigata Red Willow A CuningCutting NA •3,6' SalixSaJix lasio!epislasiolepis Arroyo Willow A Cutting NA 3,6j ,6 Salix !asiandralasiandra YellowYel10w Willow A Cuning NA 3j ,.6

SShrubJhru bs ArtemcsiaAnemesia californica California Sage C CoContainermainer S 7 BacchacisBaccbaris pilularispilularis Coyote Bush C Container S,E 7 Baccharis viminea Mule Fat DB,C,C ContainerContainer S,E 7 Comus stoloniferastolonifera Dogwood A,DB CuningCuning All 3,4,6j,4,6 DipDiplacuslacus aurantiacus Sticky Monkey Flower DB,C,C ContainerContainer All 7 HetennonelesHete:nnoneles arbutifolia Toyon C CContainerontaine r All ',I,.' Holodiscus discoloscolorr ~"...yO=Mpny DB Container All 7 Lupinus arboeusarbocus Bush Lupine DB Container All 7 PhysocarpusPh)'SOCal'pus capitatuscapitarus NNinebarkinebark A,DA,B CuttingCuning All 3,6j ,6 Prunus demissa Western Choke ChertyCherry C CoContainerntainer All 7 PrunusPntnus illillicifoliaicifolia Holly-LeavedHotly- Leaved Cherry C ContaineContainerr All 7 Rhamnus californica DwarfCoffeeberryOv.'ari Coffeebeny BD,C Container All 7 Rhamnus c:roceaaocea ....Red BerryB"'l' DB,C Container All 7 Ribes glutinosum FloweringFlowering Currant DB ContaineContainerr E 7 RlbesRJbes sanguinewnsanguineum Red FloweringFlo ....'ering CumntCUlT8J\\ DB Container E 7 RJbesRlbes vibumifoHumviburnifolium Evergreen CurrantCummt BD ContainerContainer E 7 Rosa calcalifomicaiforn ica California Wi ld Rose DB Container All 4,7,7 Rubus !minusursinU$ CaCalifornialifornia BlackberryBlackbeny DB ContainerContainer All 4,7 SaISaJ\ia\; a mellifera Black Sage C CoContainerrnainer All SalviaSaJvia sonomensissonome:nsis Sonoma Sage C Container All 1' ,7 Sal\Salvia'ja spathacia HummHwnmiingbingbirdrd Sage C Container All 1',7,7 SympboricarposSymphoric:arpos mollimolliss Creeping SnowbcrrySnowbeny AA,D,B CuttingCuning E 1' ,7 SymphoricarposSympboricarpos rivurlvularislaris CommonCommon SnowbenySnowberry A,BA,D Cuning All 4,74,7 ZauschneriaZauschneria californicacaJifornica Californiacalifornia Fuchsia C Container AllA\I 4,74,7 1,7',7 ViinnesC!l VilisVitls caljforncaJifornicaica Wild GrapeGrape BD Container AllA\I 4,7 Grounuadroversdeovert AsterAsteT chileruischilensis Western Aster B,CD,C S5<,d.. " All ClarkiaClarida amoena FaJewel!-to-springFarewell-to-spring BD,C Sool5

SS55

AR 007474 Notes

I. Red AAlderlder isis prtferredpl'tfcmd but may not be availableavailable.. White Alder mamayy be substitutedsubstituted 22.. ~ayMay require dryer climate dryer climate than exislSexists along Lower CodomiusCodomices Creek but can be tested iinn smallsmall quantities 3. Primary species for soilsoil·bio-engineering· bi~engintefing systems 4. Requires part to full shade SS.. Requires fulfulll sun 6.6. Phase 1I planting 7. Phase 11II planting

s.

AR 007475 DRAFT 3/1/013/1101 Phased CreekCreek Improvements

At the completion of the Phase I plantings, groundcover seeding can be done through manual or hydroseedinghydroseeding techniques. During thethe first two yearsyears afterafter initial planting, management practices shouldshould include the rreplacementeplacement of any losses, the manual removalremoval of invasive species and the addition of shade rrequiringequiring understory species.

PhaPhasese 2 (Years 3-5)

In the fall of thethe third yearyear after construction, species ddiversityiversity sshouldhould bebe increased through the installation of the remainderremainder of species contained in the plant lislist.t. Plant species propagated under contract shoushouldld be available at this timetime.. The removalremoval of invasive species and the replacementreplacement of any canopy tree losses should continue throughthrough Phase 2.

Plant Collection

There are several loclocationsations where cuttings of willow,willow. ddogwood.ogwood, and ninebark could be collected on a sussustainedtained yield basis.basis. Negotiations with park management agencies will be needed to oobtainbtain the plant materials.

Irrigation Systems

TempoTemporaryrary irrigation syssystemstems can be used to increase survival of the plantings. Irrigation will be most beneficial to plantings conductedconducted near the top ooff the bank. If irrigation is used, watering regimesregimes should be infrequ.e.r'!te.l""lt., with long duration to promote deep rootroot growth and for survival after ththee removal of the syssystem.tem. Temporary irrigatioirrigationn should be desigrieddesigned to last for thrthreeee to ffiveive years before itit is removed.removed.

Waterways Restoratitionon Institute 57

AR 007476 DRAFT 3/1101 Phased Creek ImpImprovementsrovemen ts

77.0.0 VEGETATIONVEGET AnON MANAGEMENT ANDAND CHANNELCHANNEL MMONITORINGONITORING

After the initialinitial construction of a project reach.reach. a second phasephase of tthehe construction is to observe how the channelchannel is perfonning and make appropriate physical adjustments to channechannell banks,banks, soil bioengineering systems,systems, erosionerosion controlcontrol measumeasuresres and rock wiers. This is peperformedrformed over a tw'otwo year period A second phase planting is a1so installed two yearsyears after the firstfrrst construction planting isis put in.in This is second phase planting takes inintto consideration the fact that some plants have to be planplantedted aIterafter there is some initial planplantt growtgrowthh and shading in orrdderer ttoo survive. AtAt this timetime,, it also makes sense to repairrepair irrigation lines and replace damaged tree stakes oror containercontainer plantsplants. These activities are consideredconsidered part of the projectproject construction and appearappear in thethe ppr~jectr~ject construction costscosts table as second pphasehase rrevegetatievegetationon and stream flow and geomorphic monitoring. The costs descridescribedbed in this section should not be cconfusedonfused with future and on-goingon-going creek maintenancemaintenance costs.costs. These needs and costs are addressed in the next section of this report.

ManManagementagement andand MOnitoringMOnitoring ActivitiesActivities

• ChaIUlelChannel stability and fl ood flow capacity

• AdjustmenAdjustmentt of rock wiers

• Adjustment of erosion controcontroll systems

• Correction of ovoverbankerbank drainage erosion

• IInstallatinstallationon of sstreamtream gages and measmeasuringuring of floodfl ood flows

• CCross-sectionross-section and pprofilerofile survesurveysys

SSecondecond PhPhasease RRevegetation,evegetation, MonitOMonitOringring

• PlantPlant shade reqrequiringuiring containecontainerr pplantslants

• Replace dead and damaged plantsplants

• Replace damaged oror lost trtreeee stakes and irrigation sysysstemtem components

ChannChannelel SStabilitytability and Flood CControlontrol CaCapacitypacity

Typica1lTypically,y, aIterafter a design suchsuch as propproposedosed herehere is construcconstructed,ted, tthehe creek wiwillll fine­ tune iitsts meander,meander, create a cchannelhannel thalweg-ahalweg-a deeper, llow-flow-flowow ssummeummerr flow cchannelhannel and sortsort its sediment and bed matematerialrial into poolpools,s, riffles and poinpointt bbars.ars. This is usually accomplisaccomplishedhed within the firsfirstt ttoo second wwinterinter following construction.

WatWaterwayserways Restoration InstituteInstitute 58

AR 007477 CRAFTORAFT 3/1f013/1(0 1 Phased Creek Improvements

During these first two winters, therefore, creek projects are carefully monitored during and after each significant winter stonnstorm to assure that the channechannell slopes and grades and shapes are attaining an equilibrium condition. TypicallyTypically,, a few adjustments are made to rocks which serve as grade controls, erosion control plantings on banks, and to overbank drainage coming from storm drains,drains, parking lots or streets.streets.

The second condition monitored is to record the actual flood channel capacity of the creek system. This important step has been left out of many conventional flood controlcontrol projects of the past. At some future date communities can be surprised by how much less (or how much more) flood flow capacity the modified channels have.have. Cordonices Creek will continue to be affected by a diversity of variables including culvert performance, street runoff, channel meandering and plant growth iinn regards toto the flood dischargesdIscharges the creek will convey. A crest gauge will be installed at the location of the old Fifth Street culvert and between the post office and the AAlbanylbany ChildrenChildren's's Center to monitomonitorr flood velocities and stages of storm flows. A rating curve will then be created which vvill indicate how deep different flood discharges will be on the newly created landscapelandscape.. Two nonormalrmal (or above normal rainfall) winters should provprovideide enough time to establish a working rating curve. The rating curve can of course bbee iimprmprovedoved over time.

MOnitoring of the pphysicalhysical adjustments the channel is making is done by surveying monumented channel profiles and cross-sections. An as-built survey is done immimmediatelyediately after construction and is a construction budget item The degree to which the channechannell is making minor-or mmajorajor adjustmeadjustmentsnts is then assessed from these as-built surveyssurveys.

The National Marine Fisheries Service and U.S. FishFish aandnd Wildlife Service may rrequireequire some habitat and or passage improimprovementvement analysisanalysis for steelheadsteel head. If soso,, these improvementsimprovements would be prescribed in the pennitpermit requirements.ements.

SecondSecond PhaPhasese RevegetationRevegetation MMonitoringonitOring anandd MManagementanagement

Second phase planting, vegetation monitoringmonitoring and management achieves three basic objectives. The firstfi rst is to detennine whether there iiss an acceacceptableptable llevelevel of survival of planted species, which shoshoulduld be aann 80-85% survival rate given a highighlyhly dense planting desdesign.ign. The second objective is to assure that some of the second tier or llaateter successsuccession·speciesion·species which grow up under the shade of the pioneerpioneer species areare pplantedlanted. The third objective is to assure that irrigation systemssystemS are operating.

SomeSome popular ripariparianrian species such as ferns,ferns, irises and floweringflOWering herbaceous pplantslants will not survive unlessunless theythey are planted in a secosecondnd plantingplanting after a shadshadinging canopy has dedevevellopedoped.. This project is best scheduled in the second year after~ter the initial planting pprrojectoject.. At the time this final pplantinglanting is comcomplete~pleted, irrigation systems are

Waterways Restoration InstituInstitutete 59

AR 007478 DRAFT 3/3/11011/01 Phased Creek ImproImprovementsvements overhauled and missmissinging or broken tree stakes are replaced. The irrigation syystestemsms are checked tw'icetwice a yearyear for the firstfirst three years to assure their operating conditioncondition..

Stream Maintenance

Maintenance of lower Codomices Creek up to now has occurred largely at the initiative of the University Village maintenance department with some assistance from non ~~pprofitrofit citizen organizationsorganizations.. The lower Codornies Creek design team recommends that this future responsibility be more equitably shared among the University, citizen groups and the two cities using a Joint Maintenance Agreement.

This creek improvement project should greatly reduce the historic need for excavating and grubbing out cloggeddogged charmels and culverts. The onlonlyy maintenance that should need to occur is the supervised pruning of lower branches of willow and cottonwood cuttings. In-channel cattail, rushes, reeds and watercress growth should be removed during the first 3-4 years while the stream side vegetation is maturing into a shaded corridor. Monitoring the mouth of the 8th Street channel should also occur to ensure its free flow during storm events.

Maintenance costs and activities should be shared by streamside residents,residents, the cities, and the universityuniversity.. Maintenance is currently occurring between 9thtt1 and 10th streets by Eco-CityEco ~ City Builders and Body Time. Other reachesr:eaches of CodornicesCodomices Creek could be adopted by Friends of Five Creeks, for exampleexample.. Maintenance can involve conservation corps crews as necessarynecessary.. Every year,year, the Urban Creeks Council has brought yyououthth pprogramrogram volunteers from Richmond and Berkeley to help weed along the creek corridor, but many weed species on the bank side slope are also shaded out over time. Future cost estimates are going to depend on these creativecreative institutional arrangements.

MaintenanceMaintenance Activities

• In channel removal of rushes and reeds

• Bank slope weeding

• Pruning of tree species

Waterways RestorationRestoration Institute 60

AR 007479 DRAFT 311101 Phased Creek Improvements

8.0 PERMITTING

Permitting RequiremenRequirementsts for ProposedProposed ChannelChannel Modifications

The following agencies will have ppermittingermitting aauthorityuthority oveoverr any creek improments pproject:roject:

1. RegionalRegional Water Quality Control BoardBoard (RWQCB) WaterWa ter quality certification or waiver (Oean(Clean Water Act §401)§40t)

2. U.S. Army Corps of Engineers (COE) Oean Water Act §404 Rivers and HaHarborsrbors Act§10Act§IO permit

3. California DepaDepartmentrbnent of Fish and Game (Cr:x;G)(CDGG) Streambed.Streambed Alteration Agreement (Fish and Game Code §1601)

Special status species surveys required. by the UniversityUniversity Village and Albany/ NorthwesNorthwestt Berkeley Properties ElR (i(i.e.e. red-legged frogs) and indicatindicateded by site conditions (i.e. steelheadsteelhead and western pond turtles) have not been perfonneperformedd to date. Depending on the rresultsesults of these surveys, and at the discretion of the California Department of Fish and Game (CDFG), U.S.U.s. Fish andand Wildlife Sen" .c'o 0 (USFWS) and/orand/or ththee National Marine Fisheries Service (NMFS), incidental t,,[~!....,~-;! -;: pennitspermits mamayy also be required for some activities.

PotentialPotential Permitting Issues

As a condition of its appapprovalroval for the streastreamm channechannell mmcxiificationsooifkations, the RWQCB hhasas requested that tthehe redeveopment of thethe HarrisonHarrison StreetStreet playing fields and University Village housing include the implementation of stonnwater/urbanstormwater/urban runoff treatmenttreabnent andand control measuresmeasures ttoo minimize impacts toto water quality prior to dischargedischarge into the creek (RWQCB 2000)2000).. A prepre-design-design consultationconsultation withwith federal and state regulatoryregulatory agencies also producedproduced a recommendation that the wholewhole project area from San PabloPablo AvenueAvenue to the railroad tracks and bypassbypass and Village Creek channel be designed.designed and planned as a whole because the permitting agencies did not want piecemeal permit applications for differendifferentt rreaches.eaches.

Recent surveys indicate that "healthy"healthy popupopulations"lations" of steelheadsteelhead occoccurur in the creek as far upstream as the BART overpass1l • Historically, both steelheadsteelhead and salmon spawned in the creek (Mortimer, 1999)1999).. San Francisco Bay (including(including any ririverver reaches or estuarine areas accessibleaccessible to steelhead)steelhead) was recently deSignated ccriticalritical habitathabitat foforr the Central California Coast steelheasteelheadd (Federal RegisRegisterter 2000), which

I Tom Dudley, U.U.C. Berkeley Environmental Studies Lecturer, personal conununicationcommunication 2000

Waterways RestorationRestoration Institute 6611

AR 007480 DRAFT 3/1/01 Phased Creek Improvements indicates that Section 7 (Endangered Species Act) consultation with the USFWS andjand/ or NMFSNIvfFS will be initiated by the COECaE whether or not steelheadsteel head are actually observed within the project area. Given these considerations, surveys for steel head in the appropriate season may be a requirement of the CaECOE permit. Also, compliance with the NMFS guidelines for development adjacent to steelsteelhead head habitat such as those cited in the proposed Endangered Species Act 4(d) rule (Federal Register 1999) may be requiredrequired by the CaE.COE. NtvtFS guidance for development cited in proposed 4(d) include provisions such as:

• Adequate (preferably(preferably 200 foot) vegetated riparian setbacks, induding prevention of mechanical entry of disturbance within the inner 50 feet setback.setback • Avoidance of stormwater discharge impacts to the water quality or quantity, including the sedimentation of contaminant discharge.

• Design of landscaping to minimize lalawnwn areas, conserve water and limit the use of herbicides, pesticides and fertilizers within the development.

A certified NEP A document or proof of exemption hom the NEPA process is requiredrequired to obtain an individual COE permit. Activities conductedconducted underunder COE NationwideNationwide Permits are consideconsideredred approved pwsuantpursuant toto NEP A. HOHowever,'wever, given the nature of the project, the possible presence of listed.listed sspeciespecies and the amount of jurisdictionaljurisdictional acreage involved, permitting the proposed activities under a Nationwide Permit is unlikely. NEPA review has not been perfonned toto date and would have to be completed before issuance of the COE permit.permit

Waterways Restoration Institute 62

AR 007481 CRAFT 3/1/01 Phased Creek Improvements

9.0 PROJECT COSTS

Estimated costs for creek restoration from the railroad tracks to San Pablo Avenue including both a Phase 1 and Phase 2 construction is about $1.38 million in 2001 dollars. This cost estimate is based on the costs of previous restoration projects constructed by WRI on CodomicesCodornices Creek and other similar East Bay sites and therefore do not include a profit margin. but represent actual iinstallationnstallation costscosts.. Design documents and bidding, as well as some other"other "sof soft"t" costs, are not included. Because it is assumed that a design-build project implementation can save these costs. This total cost estimate includes the costs for management and monitoring described in the previous section.

The costs include a phased planting approach in which shade requiring pplantslants are installed two years aiterafter the construction year and damaged iirrrrigationigation components and dead or damaged plants are replacedreplaced..

Preliminary Cost Estimate

This section presents the preliminary cost estimates for final design and implementation of thetile restoration plan. This cost estimate hashas been made using detailed urtitunit cost va1uesvalues from similar East Bay projects completedcompleted by WRl The estimates presented herein therefore represent a high degree of reliability for purposes of developing grant applications and government budgets.budgets. Actual costs will likelikelyly vary due to inflation, fue l costs, and unforeseen field conditions. 1hisThis cost estimate asswnes that thetile WatenvaysWaterways Restoration Institute (WRl)(WRJ) performs the work as a design-build project and oversees field construction of ththee project.project.

The following additional assumptions are contained within this cost estimate:

• No hazardoushazardous waste or environmentalenvironmental issuesissues are included in thetile project budget

• A limited volwnelwne of debris encountered during excavation activities has been assumed. Significant additional ddebrisebris has not been induded.included.

• The cost estimate has been prepared assuming each reach and phase of the project will be implemented separately. Some cost savings may be realized by implementation of multiple project reaches at the same time.

• Several cost items (such as bridges, trails) have beenbeen marked as "Assumed cost. Final cost by others".others", These costs budget items have not been fully verified in this preliminary design budget.

Waterways Restoration Institute '63

AR 007482 TABLE 9-19- 1 Preliminary Design-BuildDesign·Suild Construction and ProjectProject ImplementationImplementation Cost Estimate Lower CodoCodomicesmices Creek April 20, 2001

,.~,~: ~~~,:~:.:fee;: t . 900' meander distance

64

AR 007483 TABLETABLE 99-1-1 PPrelimireliminarynary Desiiggn-Buildn-Build ConstructionConstruction aandnd PProrojectject IImpmpleementationmentation Cost EEststimateimate Lower Codomices CreekCreek AprilApril 20, 2001

11

2-2 - 6th street (phaSe II) • 350' linea, feet· 420' ~eand.~' dJs.!! nce::':;~~;:~:i;lr;rl

65

AR 007484 TABLE 9-1 Preliminary DesignDesign·Build-Build Construction andand Project ImplementationImplementation Cost Estimate Lower Codomices Cree k April 20, 2000011

Ii Ii

"

66

AR 007485 TABLE 9-1 Preliminary Design·BuildDesign-Build Construction and Project Implementation Cost Estimate Lower CodornCodornicesices CCreekreek AprilApri1 2020,, 2001

,

"

"

67

AR 007486 TABLE 9·'9·1 PreliminaryPreliminary Design-Build COnstructionConstruction and Project ImplementationImplementatio n Cost EEstimatestimate Lower Codornices CCreekre ek ApnlApril 20, 2001

,II

iIit

II

6868

AR 007487 TABLE 9·19-1 Preliminary Design-BuildBuild Construction and Project IImplementationmplementation Cost Estimate lowelowerr CodoCodornicesrnices Creek April 20, 2001

69

AR 007488 TABLETABLE 9-1 Preliminary DDesign-Buildesign-Build Construction and ProjectProject IImplemmplementationentation Cost EEstistimatemate LLowerower Codornices Creek April 20, 2001 permanentermanent cross-sectcross-sections 1 .ae. $400 $400 eomorphic monitoring 1 dayday $400 $400 biologicalblo!.Qgical monitoring 1 IsIs $1 ,500 $1,500$1 ,500 biologicalbiological protectionprotection 1 IIss 52,50052 ,500 52,50052,500 report preparreparationation 1 Is $1 ,500 $1$1,500 2nd phase revegetation 1 IsIS $3,,840 $1,500$1 ,500 RReacheach 6 Construction Cost $146,822

ESTIMATED TOTAL COCOSTST:: $$1,358,6611,358,661

NotesNotes:: Specific costs will be determined by further discussion with permittinQpermitting agenciesaQencles

7070

AR 007489 DRAFT 3/1/01311101 Phased Creek ImproImprovements .... ements

REFERENCES

EIP Associates, 1997. Focused Draft Environmental Impact Report. Draft Master Plan for the University Village & AAlbany/Northwestlbany/Northwest BerkeBerkeleyley Properties­ State Clearinghouse NoNo.. 9707203997072039.. August 29.

Federal RegisterRegister,, 1999. Volume 63, No. 250250,, page 73479·7350673479-73506. Endangered and ThreatenThreateneded Species. Proposed Rule Governing Take ofof Threatened Snake River, Central California Coast, South// Central California Coast.Coast, Lower Columbia River, Central Valley California, Middle Columbia River, and Upper WillametteWillarnette River EvolutionarilyEvolutionarily Significant Units (ESUs) of West Coast Steelhead. December 3030..

Federal Register, 2000. Volume 65, No. 32, page 7764·m7.7764-7787. Designated Critical Habitat Critical Habitat for 19 EvoEvolutionarilylutionarily Significant Units of Salmon and SteeSteelheadlhead in Washington.Washlngton, Oregon,Oregon, Idaho and California. February 1616..

HernandeHernandezz,, JJenniferennifer et ata1 1994., CEQA Handbook. California Environmental Publications.Publications. San Rafael, CaliforniaCalifornia..

Personal Corrununication.Communication. Tom DudleyDudley.. Environmental Studies IInstructornstructor. University of Califorrtia,California, BerkeleBerkeley.y. May, 2000.

MortimerMortimer,, Katherine. 19991999 Draft lnitital Study for the CodornicesCodomices Creek Schematic Master Plan and thethe HarrisHarrisonon Street PlayingPlaying Fields and CodorrucesCodomices Creek IImprmprovementovement Pian.Pian. August 30.30.

Regional Water Quality Control BoaBoardrd (RWQCB). 2000. Letter from Bruce H.H. Wolfe (RWQCB(RWQCB)) to Greg HaeHaett (U.c. Berkeley). Aprrilil 1177.

Waterways Restoration InsliMInstitutee 71

AR 007490 DRAFT 3(1(013(1101 Phased Creek Improvements

Appendix A CodornicesCodomices Creek Reports and Documents

Waterways Restoration Institute

---_....

AR 007491 DDRARAFTFT 3/1/01 Phased Creek IImprovementsmprovements

Sandis Humber Jones. Flood Study for CodornicesCadarnices Creek for J.R. Roberts Corp. (November 1998).

Thomas Burke, JeffrJeffreyey Haltiner. Codomices Creek Flooding Analysis. Prepared for the University of California (October 11997).997).

City ofof Berkeley. Draft Initial Study for the Codornices CreekOeek Schematic Plan and Harrisoonn Street Playyinging Fields and Codornices Creek ImprImproovevements (1999).

Julie Katherine Isbill. UniversityUniversity VilVillagelage Creek Corridor Design.Design. Professionalional report for the Master of Landscape ArchitectureArchitecture,, UniveUniversityrsity of California, BerkelBerkeleeyy (May 1988)1988)..

JohnJohn 1.T. BraultBrault. Codomices Creek Water Quality Restoration. Senior HonHonorsors Thesis, University of California, Berkeley (1990)(1990)..

Prunuske Chatham [ncInc .o Codornices Creek Erosion Site Inventory.Inventory. Prepared foror ththee CodomicesCodamices Creek Association:Association: Urban Creeks Council and the CaliforniaCaJifornia Department of Water Resources Urban Stream Restoration Program (February 1990)1990)..

OfficeOffice ofof Planning,Planning, Design and Construction, University of California, Berkeley. Draft Master Plan"Plan, University Village and Albany-Northwest Properties.Properties. University of California, BerkeleyBerkeley [lat[laterer certified as EIR with comments and public review] (February(Feqruary 1993).

ElizabethElizabeth Andrews,Andrews, Jeffrey Haltiner.Haltiner. Flood Studies and Site PlarutingPlaruting:: Codomices and VilVillagelage Creeks at Albany Vil1age.Village. Philip Williams Associates (March 1993).

Thomas Dunne and Luna Leopold, Water in EnvirorunentalEnvironmental Planning, Freeman, Inc.,Inc., 1978 Luna Leopold" A ViewView of the River,"River/ Harvard University Press, 1994.

HanHan-Bin-Bin Liang, Jeffrey Haltiner. FloodRood Assessments of Lower Codornices Creek in thethe CitiesCities of Berkeley and Albany Between Eighth and Ninth Street (Marc(Marchh 1995)1995)..

Flood InsuranInsurancece Study, City ofof Berkeley, Alameda County.County, California. US.U.S. Department of Housing and Urban DeveDevelloppmentment, Federal Insurance Administration (March(March 1978).1978).

Carolyolyn Heath. A Study ooff the CoConnditionsditions, Politics and Management of Codornices Creek in University Village (1972).

Waterways Restoration Institutetute

AR 007492 DRAFT 311/01 Phased Creek ImpImprorovementsvements

S.E. Rantz, "Suggested criteria forfor HHydrologicydrologic Design of Storm-Drainage Facilities in ththee San Francisco Bay Region, California" Open-FileOpen-File Report, US.U.S. Geological Survey, MenloMenJo Park, California. November 1971.

Doris Sloan, Scott Stine (Editors) BerkeleyBerkeley Water:Water: Issues and Resources. Environmental Sciences GGrouproup Major,Major, University of California, BerkeleBerkeleyy Gune 1983).

Richard SchwarSchwarttz. Berkeley 1900, Daily Life at ththee Tum of the CeCentury,ntury, RSB Books,Books, Berkeley, CA (2000).(2000) .

I

Waterways Restororatioation Institute A-2

AR 007493 AppendixBAppendix B Stable Channel Design Process

AR 007494 Appendix B: Stable Channel Design Process

Stable channel design requires that a project reresultssults in a desirable active channel width and depth, slope, meander and floodplain area. As a result of monitoring for equilibrium channel shapes and meanders, local relationships have been derived for the East Bay urban creeks between drainage area and active, or bankfull, channel widths\-vidths and depths. The design process also uses relationships between the lengths of the channel meanders and the widths of the creeks based on different stream typestypes.. The stable channel design, therefore applies these localizedlocalized relationships to design a channel that shoshoulduld not result in substantial maintenance or management needs. These regional relationships are supplemented with historic information from aerial photos and survey maps that help detemtinedetermine the type of stream channels that have flowed down the reaches ·of Codomices Creek this report addresses. WRIWRl has has also done previous projects on CodornicesCodomices Creek within the project area (at Fifth - Sixth Streets and betweenbehveen Eighth- Ninth Streets) to gain experience in applying these localized averages. The next section describes how the design parameters for stable channels for each project reach were derived and quantified.

The project described in this report is based on applying the principles of the stabstablele channel restoration design. Land use constraints rarely allow for optimum condconditionsitions for creating stable channels but reasonable ssiteite plans can achieve a considerabconsiderablele stabilitystability.. This plan represents this reasonabreasonablele balance. The current creek conditions are typified by channel lengths which are too short and therefore the meandering is inadequateinadequate.. These situations result in the stream trying to compensate by attacking the banks and by head cuttingcutting.. Head cutting is currently occurring on CodomicesCodornices Creek at numerous locations because it has been straightened in the past.past Headcutting ISis one way that the creek tries to reflatten its slope. This isis typified by erosion of the bottom ·'of the creek bed,bed, which continues to travel up the stream channel in a series of waterfalls or "nick points" (Figure 5-4)5-4)..

Channels that do not achieve the correct, sstabletable dimensions require project designs which lock the channelcharme1 into place using concrete, rock banks and grade control structures. These features incur higher maintenance and management costs because they have to be repaired or replaced over time due to the constant stress exerted on them by a stream attempting to establish a stable equilibrium.equilibrium. The unstable reaches have a tentendencydency to affect the stable design reaches up and downstream from them. This Phased Creek.Creek Restoration Plan project attempts to minimize these problems.

Stream Channel Forming Discharges In order to design a stablestable,, or equilibrium channel, it is necessary to estimate the channel formingfOnning or bankfull discharge.discharge. This discharge is one of the smaller, more frequent flows that typically fallfaU betweenbetw"een the one and a half and the two year recurrence interval, or in other words,words, the flow that can be expected to occur on the average of hvo times every three yeayearsrs.. The active,active, meandering channel that is

....8-1 ,

AR 007495 formed bbyy these discharges must be correctlcorrectlyy sized. to avoid excessive erosionerosion or depositiondeposition.. Two methods are typically engaged to estimate these channel·forming flows when gauge data is not available for a stream. One estimate is derived from regional data compiled from U.S. Geological Survey stream gauge stations in which the 1.5-yearl.5-year recurrence interval discharges are plplottedotted against watershed drainage areas. A graph was developeddeveloped. that shows cross·sectionalcross~ectional channel areas and channelcharmel widths for various sized drainage areas for local East Bay streams using only infonnatiinfonnationon from East Bay gauges and restrestoratiorationon projects that have been observed. Thisnus graph has refined oonene started bbyy Luna Leopold and publishedpubliShed in Water and EnvironmentalEnvironmental Planning in 1978 (Leopold 1978).1978). A relatively recentlyrecently published graph ofof bankfull discharges as a function of drainage area published by Leopold in 1994 (Leopold 1994) for the San Francisco Bay was usedused.. WRJWRI cros,s..checkedcross--checked this with regiregionalonal relatirelationsons provided byby the U.5.GSU.5.G.S. obtaineobtainedd with drainage area and rainfall data bbyy multiple regression equationsequations for estimating the 2,2, 5, 1010,, 25 and 50 yyearear recurrence interval discharges (Rantz 1971 ). These values can be adjusted for degree of urbanization. Based upon WRIWRI's's experience, these tvvotvlo methods of estimating lowerlower level dischargesdischarges provide more reasonable valvaluesues than the HEC--II modemodell commonlcorrunonly used to estimate flood flows within a basin. (Figure 8--1B-1: FloodFlood Frequency Curve; Figure 8--2:B-2: Adjusted RegiRegionalonal Curve:Curve: Bankfull Cross·secti-sectionalonal Area as a Function ofof Drainage Area;eai Figure B·3B-3: Adjusted Regional CCurve:urve: Bankfull Width as a Function of DrainageDrainage Area).

Restoration Parameters

The Active Channel Shape The Codomices Creek project area drains a watershed area of 1.2 sqsquareuare miles. UsUsinging thithiss figure and the assumptiassumptionon that the average rainfall iiss 25 inches a yyear,ear, both the Rantz equation and the East Bay adjusted regional channel hydraulichydraulic geometry were used to estimaestimate te the active or chann~ forming flow.flow.

The flood frequency curve derived from Rantz's San Francisco Bay regression equations provided a valvalueue of about 80 cubic feet per secondsecond (cfs(cis)) discharge for the 1.5 recurrencerecurrence iintervalnterval flowflow.. Leopold's San Francisco Bay RegionalRegional data that plots bankfull discharge as a function of drainage area also provides a value of 8800 cfs. The agreement of these values gives some confidence that the findings in this report are doseclose to the correct values.values.

The East Bay regiregionalonal curve indicatesindicates that the average ccross·sectionalross-sectional area of an active channel for this watershedwatershed. drainage area is about 25 square feet and the wwidthidth is about 15 feet. Based upon experience with previous projecojectsts in this area of the watershed,watershed, it was foundund that channel widths adjust at about 16 feet. The depths appear to be abcut1.5about 1.5 toto 1.6 feet. These regionalregional values applapplyy well to Roosgensgen Band

&-2

AR 007496 Flood Frequency Curve Figure B-1

C SouSoutheasttheast Pe nnsnnsylvaylvania o Upper GrefllGreen River,iyet, WyoWyomingming E UUpperpper SaSalmonlmon RiveRiYflr.r, ldlhoIdaho F North Ca,oDlrolHin,",., & Tenne5UeTennessee - G UpUpperper Wind RiverMr,, WyomingWyoming H Yukon River., Alink.Alnh

.5 5 10 50 100 500 DRAINAGE AAEkAREA: stI511 " ,u!:;'111: Inilcsmiles SourceSource : VViewiew of ththee River,River, Leopold (19(1994)94)

Bankfull Discharge as a functfunctionion ooff drainage area for several regregionsions in the United States.

B-3

AR 007497 Adjusted Regional CurveCurve:: Figure B-2 Bankfull X-Section as a Function of Drainaae Area

• • • • •

· .-

• ~ :-!!il1I4:t r•" '" •,• ..g: , ..'"~ oi.- • -;'5 ·, ~ .. iii" ".s.5• c g0 ..,--, iiiii •"0 i~ ~ .;-0- •0 ~ • < ~ !l,g, &s• •c ~3 "'ei! co "•c ~ " ~ ..'"~ :2 • 0 "~ 0 • ~ ~i!• •c0 ,•c 0 .-c· 00 0. ."•0 '"'"> :!.:l 0 •u8 c "•~ ~:t •c '"'"•0 e,~ 0;;: '"'"

AR 007498 Adjusted Regional Curve: Figure B-3 Bankfull Width as a Function of Drainaae Area

'" '"~ ~,.-

"c -"c - 0 ::; • . ""0 ~~ '"~ •0 e • '"~ < • !'o E •c ~• ":; • " ,. ~ " •c '"~ '"~ ,;-0

8.~ "o0 ~ ~ •c •c c, o0

""•'" '"•~ '"0 ~ u •c ~" •c '"0 v ," 0 (ldJ'I1P!ttllI"J'IU'18 '" 8B-5

AR 007499 C type channels, which are very conunoncommon in the East Bay. Table B-1 shows the design parameters for a stable channel design.

ChannelChannel Meanders, Slopes and Stream Banks Meanders Historic conditions provide the pest possible information to guide the return of a more natural sinuosity to a creek as badly modified as Codomices and were used to the extent possible. It was fortunate to have such infonnationinformation in maps and photos. In the absence of historic information, indications are sought by looking at the landscape for old meanders, continuous topographic low points, and groupings of wetland vegetation. Sometimes modern-day aerial photos helphelp to identify these low points. On lower Codomices, howeverhowever,, the landscape has been so transformed and impacted by human use that this was not an option in this case.

National averages provide guidance for the relationships between bankfull channel widths and the lengths of the channel meanders. In the absence of historic or on­ the-groundthe-ground indicationsindications,, this report applies these averages developed by fluvial geomorphologists.geomorphologists. In the case of the restoration project that was designed between Fifth and Sixth Streets inin 19971997,, good historic information was not availableavailable at that time. Since then, additional historic information has been localocatedted for that reach.reach. Using the equations in Figure 4-2 entitled Geometry of Meanders, a design meander WaSwas developed that measured a restoration sinuosity of 1.3 for thisthis reach. At a later date a sketch of this channechannell was obtained that had been drawn by a OtyCity of Berkeley engineer when the FifthFifth SStreettreet culvert was put in (Figure 5-3). It confirmed that the designs based on these relationships matched the 1.3 historic Sinuosity.

Based upon experience in the East BayBay,, the following relationships are good for estimating restoration channel lengths:

• Rosgen B channel type: bankfull widthwidth x 11 = channel length

• Rosgen C channel type:type: bankfull channel x 1010 = channel length

• Rosgen E channel type: bankfull channel x 88-9=-9= channel length

When the channel meanders along Codomices Creek are desdesigned,igned, the first step is to set the objective of deriderivingving the right channelchannel sinuosity. The historical data on nearby VillaVillagege and CodonUcesCodomices Creeks providesprovides that information. The next design objective is to make sure that the meander shapes are not squeezed or drawn out too much so that they do not exhibit shapes not found in nature. For exampexample,le, one would not usually find a channel doublindoublingg over itself like an accordion on a moderately to steeply sloping valley. While recognizing there is a great deal of variabilivariabilityty in natures stream channelchannel meanders, efforts are made not to force a channelchaIUlel into shapes that would not tend to be matched to the type of landscape the channelchaIUlel flows through.through. ThereforeTherefore,, information on average channel lengths were

B-6

AR 007500 B-7

AR 007501 used to guide the drawing of the meanders.meanders. While is it not possible to transfonntransform the ccreekreek back to historical conditions as land use cchangeshanges have made this impossibleimpossible,, the objective of this pplanlan is to restore the sinuositysinuosity of the creekcreek as much as possible within existing.existing, availabavailablele rights-of-wayrights-of-way.

The next step is to draw the design meandersmeanders to fit the proper channel length within the distances in each project reach.reach. The proper sinuosity is critical to meeting the objective of having a stabstablele channel, so this is a very sensitive design parameterparameter. The next concern isis to achieve a meander length and shapeshape that is within a reasonablereasonable ranrangege of the averages calculated from the equations.

TThehe restoration design sinuosity foforr Fifth Street to the railroad tracks is 1.6. The designdesign sinuosity for FifthFilth to Eighth Streets is 1.3. UpsUpstreamtream of Ninth Street the design sinuosity is 1.22.. The restoration design conformsconfonns to what is believed will stabilize ththee now caving banks of Codomices creek.

Slopes As the discussion of existing conditions indicates, the straightened creek has an oversteepend channelchannel and has been headcutting to flatten out its slopeslope.. In many reaches the slope of the creek is flatter now than it was histOricallhistOricallyy.. To achieve an estimate of the historhistoricalical cchannelhannel bottom slope, the slope of the Codomices Creek valley was estimated oveoverr its its different reaches from San Pablo Avenue to thetlie railroad tracks using level and stadia surveys. Given the relationship of valleyvalley slope, channel slope and sinuosity under natural conditions, it was deduced that the channel slope should be steepened from Sixth to Eighth Streets and Ninth Street to San PabloPablo Avenue. At San Pablo Avenue, this planplan recommendsrecommends the culvert and channel invert be reconnected, which shoushouldld greatly facilitate steelhead migration.

StreamStream BanksBanks The 1.5 foot active channelchann~l banks are vertical or near vertical as they occur in nature. In the C-typeC-type channelschannels between Fifth and Ninth Streets wherewhere therethere is floodplainfloodplain space, thertheree is ropmroom for point bar (where deposition collects along the side of the flood channel) devedevelopmentlopment ono~ the outside meander bends. The project then slopes the terrace banks up to the top of the ground where the trail may be located using 2:1 side slopes.slopes. This is often considered too steep for ddesignsesigns in uurbanrban environments but given the constrained right of way, a 2:1 design assumptionassumption was applied to most of the slide slopes, and 3:1 slopes were used for only a few sections. The terrace banks will be revegetated with native riparian plants which once established should provide a high level of stability.

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AR 007502 Appendix C Floloodod Peaks for Codornices Creek

AR 007503 Appendix CC:: FloodFlood Peaks for CodomicesCodornices Creek

As directed, WRI adopted estimated discharges calculatedcalculated by previousprevious project consultants to the University and used these flows as the basis of the hydraulic analysis:

TableTable C·l:C-l: ComparisonComparison of of EstiEstimatedmated PeakPeak FlowFlow DiscDischargesharges (cfs)(cfs)::

FlFlowsows (cfs) FEMA 19781978 PWA 1993 PWA1997PWA 1997 SHJl998SHJl998 QQI010 660 580 -- Q50 960 - - - QI00Q100 11001100 920 1085 928 Q500 1420 - -- - Q - Discharge efscfs - cucubic bie feet per second FEMA - Federal Emergency ManagementManagement Agency PWA - Philip Williams Associates SH} - Sandis Humber Jones

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