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HomeMy WebLinkAbout11/21/2000, 3 - WATER REUSE PROJECT - APPROVE DESIGN ALTERNATIVE council M Nov. 21 2000 j agenOA nEpout mnmik, CITY O F SAN LUIS O B I S P 0 FROM: John Moss,Utilities Directogr- Prepared By: Dave Pierce, Water Projects Manager SUBJECT: WATER REUSE PROJECT—APPROVE DESIGN ALTERNATIVE CAO RECOMMENDATION 1. Select and approve Project Alternative 1. 2. Authorize the Utilities Director to begin investigation of opportunities to provide recycled water in exchange for groundwater. 3. Authorize the Utilities Director to direct the design engineer to move forward with the design of the project identified as the Initial Project, Groundwater Exchange, and the Future User portions of Alternative 1. DISCUSSION History In 1988,while reviewing options for upgrading the Water Reclamation Facility to meet new discharge requirements,the City Council directed staff to develop a project to recycle the tertiary treated effluent. In September1991, the City of San Luis Obispo filed Wastewater Change Petition#12 with the State Water Resource Control Board (SWRCB) requesting that recycled water to be produced by the Water Reclamation Facility be used for irrigation and other uses allowed by the California Department of Health Services. Six protests were filed against the petition. At this time the City began the environmental review process that included: the preparation and certification of an Environmental Impact Report (EIR), consultation with the U.S. Fish and Wildlife Service concerning potential impacts to the tidewater goby, consultation with the National Marine Fisheries Service (NMFS) concerning potential impacts to the steelhead, and consultation with the California Department of Fish and Game. After the City completed the environmental review and developed an extensive mitigation and monitoring program, the SWRCB, on June 21, 2000, issued Order 2000-07 DWR approving the City's petition to recycle treated wastewater. On September 5, 2000 the City Council approved the Water Reuse Project and a Notice of Determination was filed. In December 1997, the City Council awarded a design contract to Brown and Caldwell (B&C) for the design of the Water Reuse Project. The design is to be completed in three phases. • During the first phase of design, B&C prepared an Engineering Report. The report is submitted to the Regional Water Quality Control Board and the State Department of Health 3-1 Council Agenda Report—Water Reuse Project—Approve Preliminary Design Report Page2 Services as part of the request for a Master Reclamation Permit. That permit will approve the use of recycled water for specific types of use. This first phase of design was completed in February 2000. • During the second phase of design, B&C investigated the modifications that need to be made to the Water Reclamation Facility and alternative designs for the storage and the distribution systems. After the Council approves a preferred altemative, B&C will complete a Preliminary Design Report that documents the selected alternative and the system modeling that defines pipe and pump sizes as well as storage requirements. • During the third phase of design, B&C will prepare the plans and specifications needed to advertise and construct the project. Alternatives Investigated During the pre-design phase, two projects (identified as Alternatives 2 and 3 in the Brown and Caldwell report) were investigated to utilize the maximum amount of available recycled water to offset the consumption of potable water. As will be discussed later in this report, these altematives are not being recommended. The distinguishing characteristic between these altematives is that Alternative 2 proposes elevated storage at a location, which is not yet finalized and may require property acquisition, whereas Alternative 3 proposes storage at the existing Water Reclamation Facility site in conjunction with a pump station to provide the required hydraulic grade line. Altematives 2 and 3 have an estimated capital cost of$20.3 million. Since these cost estimates are nearly twice the project budget,Brown and Caldwell and City staff have worked to identify a more cost effective alternative. This more cost effective alternative has been identified as Altemative 1. The recommended altemative, Alternative 1,includes three identified phases: • Phase 1 - Construction of an initial phase or backbone facilities to serve existing users close to the Water Reclamation Facility; • Phase 2 - Investigation into the possibility of delivering recycled water to nearby agricultural operations in exchange for the groundwater they are currently using for irrigation; and • Phase 3 - Connection of future users to the backbone facilities developed in Phase 1. The backbone system will be developed so that it will be possible to extend the distribution system to the Sinsheimer area, downtown, and to Cal Poly at a future date if evaluation at that time deems it appropriate. It is important to note that the Groundwater Exchange element(Phase 3-2 Council Agenda Report—Water Reuse Project—Approve Preliminary Design Report Page3 2) of this alternative has not been discussed with parties outside the City, and will require additional investigation prior to implementation. The attached figure (Attachment 2) shows proposed pipeline locations for the three alternatives. The Proposed Proiect As indicated in the attached report from Brown and Caldwell the preferred alternative is to construct Phase lof Alternative 1, investigate opportunities to develop the groundwater exchange program for approximately 400 acre feet of exchange (Phase 2), and provide facilities to serve new development as it occurs within the area that can be served from the pipeline installed during Phase 1. The project so defined will provide up to 968 acre-feet per year at an average unit cost of approximately$1,035/acre-foot. FISCAL IMPACT Council has previously approved an agreement with Brown and Caldwell for the design services identified in the recommended action and no additional funding is required at this time. The construction cost is estimated to be $12.4 million. The Water Reuse Project CIP approved budget includes $8,000,000 in 2000-01 for construction. The increase in construction costs could increase the annual debt service by approximately$250,000. The increase will be included in the 2000 Water Fund analysis to determine the actual impact on rates. This is a worst-case scenario for this cost estimate. The City has applied for grant/loan funding under the 2000 Water Act that was approved by the voters as Proposition 13 in the March 2000 election. The State Water Resource Control Board is scheduled to make a decision these projects in January 2001. At this time it is expected that the funding from this source will be 25%grant and 75% low interest loan. The City has also has made an initial application for a State Revolving Fund Loan. Actual cost/fund impact will be more clearly defined after the City receives the commitment of loan/grant funds from the State and the design is finalized. ATTACHMENTS 1. Brown and Caldwell Report 2. Figure showing pipeline locations 3-3 Purpose This report serves as an Executive Decision Paper to the City Council regarding the three identified alternatives for the City of San Luis Obispo Water Reuse Project. The intent is to provide the Council sufficient information to both approve an alternative, and to authorize staff to move forward with design of the selected alternative. Background The City Council has previously approved the Final Environmental Impact Report (EIR) for this project. The project described in the EIR proposed to take effluent from the City's existing Water Reclamation Facility(WRF), treat this effluent to Department of Health Services Title 22 requirements for unrestricted water reuse for irrigation purposes, and then deliver this Reclaimed Water(RW) to identified users. The Water Reuse Project will provide a drought tolerant water supply to meet a portion of the City's nonpotable demand, will increase the water quality of San Luis Obispo Creek by reducing the quantity of contaminants discharged, will assist in complying with the Federal Clean Waters Act, and will contribute to the efficient management of the City's water resources. The City retained Brown and Caldwell to prepare an Engineering Report, a Pre-Design Report, and a Final Design for the Reuse Project. The project in its simplest form consists of three main capital components: 1. Modifications to the existing WRF. 2. A new system of pipelines for distribution of the RW. 3. Storage to allow collection of RW during non-demand hours. Discussion The most cost-effective project is a phased approach(see Alternative 1 on the attached matrix) to project implementation that maximizes RW delivery by first serving"potable offset" customers closest to the WRF,through an innovative groundwater exchange program proposed by City staff, and by planning to service future users when expected development occurs. A key aspect of this alternative is that it retains the flexibility to serve all "potable offset"customers, while minimizing the unit costs through the"Groundwater Exchange" and"Future Users"planned phases. Two other project alternatives (reflected on the attached matrix as Alternatives 2 and 3) identified in the early pre-design phase would distribute RW only to uses throughout the City that offset the consumption of potable water. The unit cost of these two alternatives is identical; the distinguishing characteristic between them is that Alt. 2 proposes elevated storage at a location which is not yet finalized and would require property acquisition by the City, whereas Alt. 3 proposes to utilize storage at the existing WRF site in conjunction with a pump station to 1 "Water Reuse Project," Final Environmental Impact Report, City of San Luis Obispo Utilities Department,3/97. 'It is important to note that this element of Alternative 1 has not been discussed with parties outside of the City and will require additional investigation prior to implementation. Decision Paper Text Page 1 of 2 3-A SLO Water Reuse Project �F /}rTA-C 1 /MCet 7— provide provide the required hydraulic grade line. Alternatives 2 and 3 are not phased projects, and they do not consider the delivery of water via the Groundwater Exchange element proposed in Alternative 1. The attached matrix provides the capital cost and a"Cost/Acre-foot"calculation for each of the phases proposed in Alternative 1, and for Alternatives 2 and 3. As can be seen from the "Cost/Acre-foot" column in Alternative 1, the most cost-effective project is to build the"Initial Project'that serves users closest to the WU, to develop the "Groundwater Exchange" element, and to then service the"Future Users." When Alternative 1 is built in this order, the cost of RW is expected to be on the order of$1,013/acre-foot.3 Building the system further to service the "Sinsheimer Area" and the"Downtown and Cal Poly Areas"produces a diminishing returns effect. The averaged cost to deliver RW to these areas would be $1,182 and $1,451 per acre- foot. The unit cost to build out either Alternative 2 or Alternative 3 is expected to be $1,980. Recommendation Brown and Caldwell recommends that the Council select and approve Alternative No. 1. We recommend that the Council authorize staff to begin investigation of opportunities to provide reclaimed water in exchange for groundwater. We also recommend that the Council authorize staff to direct the design engineer to complete the design of a project that will serve users identified in the"Initial Project," the "Groundwater Exchange"and the "Future Users" elements of Alternative No. 1. 3 These costs are simple averages of the calculated cost/acre-foot;due to the unknown start date of demands for the "Future Users,"no adjustment has been made for the time value of money. Decision Paper Text Page 2 of 2 SLO Water Reuse Project 3'5 Decision Paper Matrix - City of San Luis Obispo Water Reuse Project Alternative No. 1 Initial Project Customers Served Ac-fUyr Capital Components Capital Cost Annual O&M Cost/Ac-ft' Cost Laguna Hills Park 8 7 miles of pipelines Laguna Lake Goff Course 17 RW Pump Station 12 Laguna Middle School 26 Modifications to Laguna Lake Park 12 existing WRF HOA II(2 sites) 9 0.2 MG Storage to Los Verdes Park HOA 5 maintain creek flows State Farm Mutual 7 French Park 20 Isla Hills Park g Total this-Rase 113 $9.6 M $128 K $6,842 Groundwater Exchange Customers Served Ac-ft/yr Capital Components Capital Cost Annual O&M COSVAC-ft• Cost Ag between 101 &Madonna Distribution piping Ag near South Hi uera 1.0 MG.storage — - Total this-phase 400 $1.8 M $10 K " Cumulative 513 $11.4 M $138 K $1,762 Futures Users (Proposed/Planned Developments) Customers Served Ac-ftlyr Capital Components Capital Cost Annual O&M CosVAc-ft` Cost Margarita/Airport 215 Distribution Piping i Storage Dalidio Area 200 0.4 MG _ u Orcutt Area 40 - Total this phase 455 $1.0 M $10 K - Cumulative 968 $12.4 M $148 K $1,013 Sinsheimer Area Customers Served Ac-ftlyr Capital Components Capital Cost Annual O&M CosVAc-ft* Cost SLO Coastal Unified 7 Pipeline to Johnson Park 7 Sinsheimer Area Sinsheimer Stadium 10 0.3 MG Storage Sinsheimer Park 9 Parkwood Village _ - 5 Total this phase 38 --- $2.8 M $20 K -`�'•' Cumulative 1005 $15.2 M $168 K $1,182 Downtown and Cal Poly Areas Customers Served Ac-ft/yr Capital Components Capital Cost Annual O&M Cost/Ac-ft' Cost Cal Poly 150 7 miles of pipelines Santa Rosa Park 9 1.0 MG Storage Santa Rosa Ballfield 9 Caltrans(5 sites) 25 Hawthorne School Ballfield 5 Exposition Park 12 Meadow Park 8 Apple Farm 5 Mitchell Park 4 2 Emerson Park 4 - Total this phase - 231 $8.0 M $68 K Cumulative 1237 $23.2 M $236 K $1,451 Decision Paper Matrix ��� SLO Water Reuse Project Pagel of 2 Decision Paper Matrix - City of San Luis Obispo Water Reuse Project Alternative No. 2 Customers Served Ac-ft/yr Capital Components Capital Cost Annual O&M Cost/Ac-ft' Cost All users identified in EIR 14 miles of pipelines RW Pump Station > Modifications to existing WRF 1.5 MG Storage (Terrace Hill elevation) Total 382 $20.3 M $216 K $4,136- Futures Users (Proposed/Planned Developments) Customers Served Ac-ft/yr Capital Components Capital Cost Annual O&M Cost/Ac-ft' Cost Margarita/Airport 215 Distribution Piping Dalidio Area 200 0.4 MG Storage Orcutt Area 40 Total this phase 455 $1.0 M $10 K Cumulative 837 $21.3 M $226 K $1,980 Alternative No. 3 Customers Served Ac-ft/yr Capital Components Capital Cost Annual O&M Cost/Ac-ft' Cost All users identified in EIR14 miles of pipelines r T ,, — RW Pump Station Modifications to existing WRF 1.5 MG Storage at existing WRF :» a In-line booster _A pump station Total 382 $20.3 M $216.K_ _ $4,136 :3 Futures Users (Proposed/Planned Developments) Customers Served Ac-ft/yr Capital Components Capital Cost Annual O&M CosVAc-ft' Cost Margarita/Airport 215 Distribution Piping ' Dalidio Area 200 0.4 MG Storage s ; Orcutt Area 40 _ Total this phase 455 $1.0 M $10 K Cumulative 837 $21.3 M $226 K $1,980 *Note: "Cost/Ac-ft"is calculated as [(Annualized cost of a 20-year bond @ 3%to pay for capital cost);(Annual O&M cost)]/[Ac-ft/yr RW delivered] Decision Paper Matrix �-� SLO Water Reuse Project Page 2 of 2 /4 C A4 FA/ . ......... ... ......... .... ...... ...... ........ Propos9d Resgrvoly .5 k . ................ 16 • . ............ 40 200 20 r Reclamation Facll' j;�// X, . ......... crty of san tuis ompo.. Proposed Pump "o and Stora ae C mum r m LEGEND Alternative I Initial Project Pipeline Proposed Use Areas memommi Abandoned Unocal Pipeline Possible Future Use Areas ® me ® m i Sinsheimer Area Pipeline Potential for Groundwater Exchange momemmi ommtownfCal Poly Pipeline mamma a a m Groundwater F nge 20 Annual cortsurnoon in Ace-Feet-Future Pipeline Alternate 2 includes Initial Project, Sinsheimer Area, and Downtown/Cal Poly with Storage at Terrace Hill. Aftemate 3 includes Initial Project, Sinsheimer Area, and Downtown/Cal Poly with Storage at the Water Reclamation Facility. 3-8