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Home My WebLink About07.a. Consider joint agreement with County for Walnut Creek/Grayson Creek Levee Rehabilitation Project Central Contra Costa Sanitary District 7Q . ' BOARD OF DIRECTORS POSITION PAPER Board Meeting Date: February 18, 2016 subject: AUTHORIZE THE GENERAL MANAGER TO EXECUTE AN AGREEMENT WITH CONTRA COSTA COUNTY FLOOD CONTROL AND WATER CONSERVATION DISTRICT FOR IMPLEMENTING THE JOINT WALNUT CREEK/GRAYSON CREEK LEVEE REHABILITATION PROJECT Submitted By. Initiating Dept./Div.: Dan Frost, Senior Engineer Engineering & Technical Services / Planning & Development Services REVIEWED AND RECOMMENDED FOR BOARD ACTION: D. Gemmell—Planning & Development Services Division Mgr. JM. Petit-Director of Engineering &Technical Services Kent AlmRoger S.Bailey Counsel for the Distri General Manager ISSUE: Board authorization is required for execution of agreements exceeding $100,000. BACKGROUND: Central Contra Costa Sanitary District (District) Project (DP) 7314 will raise the Walnut and Grayson Creek levees along the District's wastewater treatment plant to ensure protection against a 0.2% ("500-year") storm event with three feet of freeboard. This is a joint project between the District and Contra Costa County Flood Control and Water Conservation District (CCCFCWCD). An agreement is required between the two agencies to proceed with implementation of the project. The existing levees that protect the District's wastewater treatment plant provide protection for less than a 100-year storm event based on the Army Corps of Engineers' current recommended flood protection requirements (100-year storm event with three feet of freeboard). In 2007, the District worked with CCCFCWCD on an interim project to desilt the Walnut Creek channel and raise the levees along Walnut and Grayson creeks. Due to site constraints, the CCCFCWCD was only able to increase the levee elevations to provide approximately one to three feet of freeboard for a 100-year storm event. The 2007 interim project was initiated due to flooding and overtopping of levees near Pacheco Creek during an approximate 40-year storm event in 2005. Based on subsequent discussions with CCCFCWCD, the District agreed to proceed with a project to raise the levees around the wastewater treatment plant to provide protection from a 500-year storm event with three feet of freeboard. Flood protection is critical for the District to prevent catastrophic failure of the District's wastewater treatment plant facilities —which could result in a stoppage of treatment service, temporary discharge of untreated or partially treated wastewater, and more than $150 million in damages to existing District assets. Page 1 of 3 POSITION PAPER Board Meeting Date: February 18, 2016 subject: AUTHORIZE THE GENERAL MANAGER TO EXECUTE AN AGREEMENT WITH CONTRA COSTA COUNTY FLOOD CONTROL AND WATER CONSERVATION DISTRICT FOR IMPLEMENTING THE JOINT WALNUT CREEK/GRAYSON CREEK LEVEE REHABILITATION PROJECT The agreement between the District and CCCFCWCD will include a description of each agency's responsibilities. Some of the proposed agreement terms include the following: That CCCFCWCD will be responsible for: 1. Serving as the lead agency on the project. 2. Obtaining all permits, approvals, entitlements, and CEQA. 3. Managing utility identification and any utility relocations. 4. Development of the project design and bid documents. 5. Bidding of the project. 6. Providing construction management and inspection. 7. Providing geotechnical, survey, right-of-way, and other assistance as required for the project. That the District will be responsible for: 1. Reviewing design and bid documents. 2. Implementing a soil import operation to stockpile and secure approximately 25,000 cubic yards of soil to reduce total project costs. Cost savings from the soil import operation will be shared between the two agencies. 3. Coordinating with the CCCFCWCD on construction access requirements and fence replacement and relocation. 4. Providing survey and right-of-way staff support to research and coordinate on boundaries and real property agreements with the CCCFCWCD. It is expected that approximately six to eight feet of right-of-way transaction to CCCFCWCD will be required at minimal costs, and there may be a potential for right-of-way trade of property. The project cost will be split 50/50 between the District and CCCFCWCD. The budget will be reviewed by both agencies and both agencies will participate in a quarterly review of expenditures to monitor project costs. DP 7341 is ranked as a high priority in the District's fiscal year 2015-16 Capital Improvement Budget and directly supports Goal One of the District's 2014-16 Strategic Plan - to Meet Regulatory Requirements for the Good of the Community and Environment. The Walnut Creek/Grayson Creek Levee Rehabilitation Project will improve the District's resiliency to storm events and flooding enabling the District to continue to provide the necessary treatment to meet regulatory requirements. Page 2 of 3 POSITION PAPER Board Meeting Date: February 18, 2016 subject: AUTHORIZE THE GENERAL MANAGER TO EXECUTE AN AGREEMENT WITH CONTRA COSTA COUNTY FLOOD CONTROL AND WATER CONSERVATION DISTRICT FOR IMPLEMENTING THE JOINT WALNUT CREEK/GRAYSON CREEK LEVEE REHABILITATION PROJECT ALTERNATIVES/CONSIDERATIONS: The Board of Directors may decline to authorize an agreement and delay the implementation of the Walnut Creek/Grayson Creek Levee Rehabilitation Project. FINANCIAL IMPACTS: The District will commit to 50 percent of the project cost for implementing the joint Walnut Creek/Grayson Creek Rehabilitation Project. The project cost is estimated at $2.2 million, and the District's share is $1.1 million. With implementation of the proposed soil import operation, the District costs may reduce by up to $500,000 resulting in a total of$600,000 required from the Capital Improvement Budget. The District currently has budgeted $600,000 for this project under DP 7341. Any additional funds would be acquired from contingency funds or by the delay of other capital improvements. COMMITTEE RECOMMENDATION: This matter was discussed at the Engineering & Operations Committee meeting on October 7, 2015 and the Committee recommended presenting this matter to the Board of Directors for consideration. RECOMMENDED BOARD ACTION: Authorize the General Manager to execute an agreement with Contra Costa County Flood Control and Water Conservation District for implementing the joint Walnut Creek/Grayson Creek Levee Rehabilitation Project. Attached Supportinq Document: 1. PowerPoint Presentation:Joint Walnut Creek/Grayson Creek Levee Rehabilitation Project Page 3 of 3 ATTACHMENT 1 Item No. 7.a. Joint Walnut Creek/Grayson Creek Levee Rehabilitation Project Danea Gemmell Paul Detjens Planning and Development Senior Engineer/ Division Manager Program Manager CCCSD CCCFCWCD February 18, 2016 Central Contra Costa Sanitary District ~ 40-Year Flood Event near Pacheco Creek December 31 , 2005 Flood Event ppop Imhoff Dr. bridge looking south along Along east side of Walnut Creek looking Grayson Creek north towards Imhoff Dr 2013 Study Identified up to $ 146M i n Potential Damages � Tjr- I IRA 00 woo �► �� +i. `'' � air_'= g/" OAOI Y„ w 01 .29.2013 G '7`, i .22j PW I Influent Pumps located below grade Final/Standby Effluent Pumps located below the Pump & Blower Building D Background • Major storm events lead to overtopping of levees near Pacheco Creek (-40 year event) • Flood Control District (FCD) Project to desilt Walnut Creek Channel • FCD Interim Levee Project to raise western levee of WC Channel/Grayson Creek April 9 Board accepts Integrated Regional Water Mgmt Plan (IRWMP) for Prop 1 E Grant 2013 9 Joint Project with FCD to raise levee with 25% share ($550K) June • Notice of unsuccessful Prop 1 E Grant 2013 • Enterprise Committee presented w/FCD request to split project with 50% share (or July $1 .1 M) w/ potential to reduce costs with soil import program on Kiewit property 2013 • Staff received direction to proceed with plan on Kiewit property June ' Adopted FY2014-15 CIP (DP 3741 ) includes Walnut Creek Channel /Grayson Creek 2014 Levee Rehabilitation Project ($620K) Existin Ca ital Projectj g p ( DP7341 ) • Priority Ranking : High Wffia1 gaWf�eyaon CrteF laves FeM1aallnallOn • CIB Program : Treatment Plant Oe 4kaean E'4'naa'+�6"3aam9 sM MNMaw�Saw:z ComJA 100% Lead Agency: FCD MCmYa Gah QaaN btl Dred aH W6r Comervatim GmiC(FCOj. rtmy a.mniax grnaxeemrJ.ne Mwmroam Geasm creenawm levee axeeteamM h FCD.tl I:SAanYCo`Ga M Enprers 1UaACEi.x+9 dYrLagYa�al9 dM mdntdMlE MeR Total Project Cost: $2.2M �aa mdAOa�NNaaR]sew0•-Ala6pa Iv.Nr Walna OeaF vunrcl aM nrse Te raem krws¢�WLiullan0 C+a'Ma 6atlai BssM m rxml awYedM.Te k�e[s m'[*h a�'da VrNeubnfrun aSFYaxfbm M eunrtt Ilml pmusmswdvE by h CNdania Jepa�enend WabResaueces rs m pmvue 6.ma G aawr., rcewmORAA6eNnitlatlmmLU tlrtKm District Cost Share: 50% maven@6ya.yMnl W`F,i Xacd±�oMWn MM b a30LLyW YM avlattrnm 3M.¢ heaNard.Tie FCO W M Nekac alta-YafMYmlmxMtlw MPc WI We++�e stµYMas naattElx M'T Tiaxat]snmu[hnsnlYiaOeri Current Protection : < 100 yrs Fcoe Wm.gysn nrav+°.e»aapev nmpm.emvnx.�zce»�:r.-a. UamRannWea acapvg atl smnnp vi m Olm1h/Iw�p Mb6uta le uaaG x kvm mYe nal v�mdxmpnveah�6um mard®msaf appvtinnaly WJ1.TM GfPvl ail. Proposed Protection : 500 yrs EamaT—. r Faase 9+on' e.Q,1 Rv`Ya n'aLu ren � W iY ULLfs W # W $ eaav5 115'16 '.-�"r 16 W W b W b W MWR 1:l: 1*16 11.b W W W W W W N W W W MW NW,WO WWW] lP9 D Project Location y(.. / /' .M q r y_ r USACE Flood Protection Standard is 100-Year w/ 3-ft Freeboard Pre 2007 2007 - 2018 Post 2018 <<<100 Year Protection -100-Year Protection 500-Year Protection ? Freeboard 1 to 3-ft Freeboard 3-ft Freeboard D Project Scope • Increase embankment to 500 year Flood Projection with 3-ft Freeboard • Expected 6' to 8' ROW transaction to FCD at minimal costs (possible ROW trade of property) • Relocate/Replace fence to bottom of slope • Soil import operation to stockpile & secure 25, 000 cy of fill to minimize project costs • FCD planning a separate project to desilt Walnut Creek Channel D O Alk Ah • • Ah • Ah 1 F / Iw At i� in �� (` ,�. •• � ��,r.(^{�, V \ T nl.. Ift A 77 'FALM, owl ket ^1 u�'•'�• �I1: ' �� • 'I��u r �",r..� � „ntP^� A �i�il* � 11 i...,n!1 Proposed Levee Modifications Current Proposed Proposed Levee Location Location Freeboard for Freeboard for Elevation # Description 100-Year Flood 500-Year Flood Increase (feet) (feet) (feet) Basin B / 1 Walnut Creek 1 .5 3.0 3.0 Channel Near Confluence of 2 Walnut and 3.7 3.0 1 .8 Grayson Creeks Headworks / 3 Grayson Creek 2 . 1 3.0 2.2 � : D Project Benefits • Levees will meet current levee protection standards • Levee will protect $ 150M+ of existing treatment plant assets • Increased protection of overall plant site and personnel • Increased protection from catastrophic failures, plant shutdowns , extended shutdowns , emergency discharge of untreated wastewater D Agreement Terms • 50%-50% split between CCCSD and FCD with estimated $2 . 2M project cost • Both agencies will share in import soil savings • Budget approved by both parties with Quarterly review of expenditures to monitor costs • Budget includes staff costs for CCCSD & FCD D Flood Control District ' s Role • Lead agency • Obtain permits , r approvals , entitlements & C E QA • Manage utility relocations4 • Produce design documents • Bid project • Construction inspection and management CCCSD ' s Role Lead 25 , 000 cy soil import for operation at Kiewit property f , Provide • i `YK,T W1,si'• a t ROW support .' e• .•L. MSP > Review design I • bid documents Coordinate , - • fence relocation District Staff Recommends The Board of Directors authorize the General Manager to execute an agreement with the Contra Costa County Flood Control and Water Conservation District for implementing the joint Walnut Creek/Grayson Creek Levee Rehabilitation Project D M r G . \ f u � o tAl1 - ••,Y \ Ai ITI -tea Im\N;17 r U n 44 e