SITES RESERVOIR ALTERNATIVES EVALUATION - Reclamation District 108

Sites Reservoir Alternatives EvaluationFigure 1. Alternative D Key Features2.3Alternative EAlternative E provides an alternative that falls between Alternatives C and D in terms of costs andbenefits. Alternative E is similar to Alternative C, but without pumped storage, a new intake facility forthe Delevan pipeline, and the south bridge. Alternative E (Figure 2) includes the following features: 1.8 MAF Reservoir – Like Alternative C, the 1.8 MAF reservoir would include two main dams: GoldenGate Dam and Sites Dam. Golden Gate Dam, at Funks Creek, would be constructed to a height of310 feet above the streambed. This earthen and rockfill embankment dam would have a crestlength of 2,250 feet and require approximately 10.6 million cubic yards of material for construction.Sites Dam, at Stone Corral Creek, would be constructed to a height of approximately 290 feet abovethe streambed. This earthen and rockfill embankment would have a crest length of approximately850 feet and require approximately 3.8 million cubic yards of material. Alternative E would alsorequire the construction of nine smaller saddle dams with a total fill volume of approximately7.5 million cubic yards. Funks Reservoir – Alternative E would not include expanding Funks Reservoir capacity beyond itscurrent design size to provide pumped storage capability for dispatchable power. However, theexisting Funks Reservoir could be better adapted for use under this alternative. To improveoperability, this effort would require removal of sediment (approximately 1.6 million cubic yards)that has accumulated in the pond over the years. There would be no change in the operating range5

Sites Reservoir Alternatives Evaluationfor Funks Reservoir under this alternative and it would continue its existing function as a regulatingreservoir for the Tehama-Colusa Canal. TRR, Pump Station, and TRR Pipeline – Water conveyed by the GCID Main Canal would be conveyedinto a future TRR. The TRR would provide regulatory storage to balance out normal and emergencyflow variations in the 40 miles of GCID Main Canal between the headworks pump station atHamilton City and the TRR. The reservoir would be formed by a combination of excavation belowgrade and construction of low-perimeter dikes. Operating water levels in the TRR would becompatible with water levels in the GCID Main Canal to facilitate operation. A valve-controlledbottom outlet pipeline will be provided for the TRR to Funks Creek to facilitate reservoir drainage,and an emergency overflow spillway to Funks Creek will also be provided. A new pump stationwould be constructed as part of the TRR to convey the water from the reservoir to Funks Reservoirvia a new TRR pipeline for ultimate delivery to Sites Reservoir. The pipeline would span 3.5 milesand consist of two 12-foot-diameter concrete pipes. Water also could be released back to the TRRfrom Funks Reservoir via the TRR pipeline to meet irrigation needs supplied by the GCID Main Canal. Delevan Pipeline – The approximately 13.5-mile-long Delevan Pipeline would convey water fromFunks Reservoir to the Sacramento River for releases. The pipeline would consist of two 12-footdiameter reinforced-concrete pipes, buried with 6 feet of cover (4 feet less cover than Alternative C,but sufficient to ensure effective operation), with a capacity of 1,500 cfs for release. Sacramento River Discharge Facilities – The Delevan Pipeline would terminate at an energydissipating valve house and spillway chute at the Sacramento River. The valve house would belocated just above the current design Sacramento River flood level at the site for the adjacentlevees. From the valve structure, release up to 1,500 cfs of water would flow down a short channelsection before reaching a baffle block spillway leading down to the river. The downstream side ofthe spillway exposed to the river would be fitted with fish barrier racks to prevent migrating adultfish from entering the spillway chute. The release structure is located in a reach of the SacramentoRiver that is protected by a federal project levee system administered by USACE and CVFPB. North Road Alignment – Alternative E includes a north road alignment instead of the south bridgeincluded in Alternatives A, B, and C. The north road alignment has had more evaluation to date, buta south road alignment would also be possible. Either of the alternative road alignments wouldrequire additional evaluation prior to finalizing the EIR. Recreation Areas – Alternative E includes Stone Corral, Antelope Island, and Lurline Headwatersrecreation areas.6

Sites Reservoir Alternatives EvaluationFigure 2. Alternative E Key Features3.0COST ESTIMATIONThis section discusses the cost estimation methodology; provides updated costs for Alternatives A, B,and C; and provides cost estimates for Alternatives D and E.3.1Cost Estimation MethodologyAllowances and Contingencies: While preparing the previous cost estimate for Reclamation, URS haddiscussions with Reclamation regarding the various allowances and contingencies to be used to preparethe feasibility-level cost estimate. Subsequent review by Reclamation’s Design, Estimating, andConstruction team suggested that these allowances might be too conservative and should be furtherverified. Table 2 presents the values that URS applied in the initial estimates developed for Reclamationalong with revised allowances, developed by URS, used for the JPA estimates.7

Sites Reservoir Alternatives EvaluationTable 2. Allowances and Contingencies for JPA zation5%5%Unlisted Items10%5%Construction Contingency20%20%Facilitation (Contracting, Outreach, etc.)3%3%Geotechnical on Management10%6%Total62%50%Estimate Base and Escalation: The estimate base is December 2013. This base allows for directcomparison with the cost estimates previously developed by Reclamation and DWR. The estimate doesnot include escalation of construction costs to a Notice to Proceed date.Construction Schedule: A construction schedule was prepared for the JPA with the intent ofstreamlining the time required for design and construction. The more aggressive schedule reduces thecombined time for engineering and construction from 12 years to 10.5 years. Attachment 2 includes theconstruction schedule.3.2Cost EstimatesTable 3 presents updated cost estimates for Alternatives A, B, and C, including the revised JPAallowances/contingencies and the cost estimates for Alternatives D and E.Table 3. Construction Cost Summary (with JPA Contingencies)Alt AAlt BAlt CAlt DAlt EFeatures1.3 MAFNew Intake1BridgePump Storage1.8 MAFNo Intake1BridgePump Storage1.8 MAFNew Intake1BridgePump Storage1.3 MAFNo Intake1North Roadw/o Pump Storage1.8 MAFNo Intake1North Roadw/o Pump StorageConstructionCost Estimates 3.2B 3.6B 4.1B 3B 3.5B1. Refers to new intake structure on the Sacramento River.Alt AlternativeB billionMAF million acre-feetw/o withoutAttachment 3 provides a more detailed breakdown of the cost estimates for specific facilities forAlternatives D and E.8

Sites Reservoir Alternatives EvaluationURS also has prepared a cost estimating menu to make the cost of individual facilities more transparentand facilitate the evaluation of alternative costs. Attachment 4 provides the cost estimating menu.4.0BENEFITS EVALUATION4.1MethodologySection 79754 of the California Water Bond (Assembly Bill 1471, 2013-2014 [AB 1471]) (State ofCalifornia *California , 2014) requires the Water Commission to develop and adopt “methods forquantification and management of public benefits” by December 15, 2016. It is likely that furtheranalysis of benefits will be required at that time to refine the results presented in this technicalmemorandum with the final methodology to be published by the Water Commission. Nevertheless, themethods utilized in the analysis to date are consistent with the methods utilized for the Shasta LakeWater Resources Investigation Feasibility Report (Reclamation, 2011) and the Upper San Joaquin RiverBasin Storage Investigation Feasibility Report (Reclamation, 2014). The analysis of benefits for North-ofthe-Delta Offstream Storage Investigation 2013 Progress Report (Reclamation, 2013) has beenpreviously reviewed by both DWR and Reclamation economists. The more recent analysis for the JPAdocumented in this memorandum builds on these results and analysis. It is unlikely that the WaterCommission will require a methodology that substantially differs from the approach presented here,although some refinement of the values is expected.All five categories of public benefits included in the Water Bond were evaluated in the analysisperformed by the JPA. Water supply benefits are not recognized as a public benefit under the WaterBond, but were also included as a part of the JPA analysis. One category previously included in theanalysis by Reclamation, hydropower generation benefits, was not included in the recent evaluation ofAlternatives D and E. Without pumped storage, these benefits would not be a significant fraction of thetotal benefits and they are not identified as a category for public benefits in the Water Bond. The sixcategories of benefits include: Water Supply – One of the most important decisions by the Water Commission in establishing amethodology for determining the value of public benefits will be the approach for valuing watersupply benefits. Reclamation typically assigns significantly higher values for water supply use andM&I water supply (consistent with current market value) than for agricultural water supply.However, it can be argued that assigning a higher value to water supply than to water providingpublic benefits underrepresents the public benefits for any project. For this reason, the Sites JPAbenefit analysis uses a blended water supply benefit estimate combining agricultural and M&Ibenefits based on projected future supplied water quantities (i.e., a weighted average). Based oncurrent water quantity allocations, the estimated blended water supply benefit values for bothAlternatives D and E are approximately 917/acre-foot (AF), while Alternative C has a lower blendedwater supply value of approximately 823/AF. Use of these blended supply water values result in amore conservative and balanced valuation of the project’s total water supply benefits compared toits public use benefits.9

Sites Reservoir Alternatives Evaluation Ecosystem and Water Quality Benefits – Section 79753(a2) of the AB 1471 (California, 2014)restricts water quality benefits to benefits within the Delta or other river systems that providesignificant public trust resources. Water quality benefits may also be derived by improvinggroundwater quality. This definition differs from the approach used by Reclamation for both SitesReservoir and the Upper San Joaquin Storage Evaluation, which focused on water qualityimprovements in exported water for its benefits evaluation. The estimation of ecosystem and waterquality benefits, therefore, was revised from the approach used in the Progress Report(Reclamation, 2013). The revised approach identified future ecosystem enhancements in the form offlow releases that will improve downstream habitat, enhance river water quality, and ensureseasonal river flows that benefit fish populations. The value of these future reservoir releasesrepresents the opportunity cost between utilizing releases for water supply versus ecosystemenhancement and water quality improvement. The blended water supply value was used to developa conservative estimate of the benefits of the ecosystem and water quality flows. Coldwater Pool – In addition to the ecosystem enhancement and water quality improvementsdiscussed above, Sites Reservoir would also create cold water benefits by enabling increased waterstorage in Shasta, Folsom, Trinity and Oroville. The value of the cold water benefits was based onthe stored water’s potential agricultural supply use value and is consistent with the previousbenefits analysis for DWR and Reclamation. Emergency Water – Benefits were determined based on the emergency water benefit values fromthe Upper San Joaquin Storage Investigation (USJSI) and Sites’ Reservoir comparative expectedwater availability as a future emergency water supply source. The USJSI’s methodology fordetermining future emergency water benefits was based on the probability of a water supplydisruption occurring, the expected duration and timing of the disruption, and the resultingmagnitude of the water supply shortage experienced by urban water agencies. The value of thewater emergency supply benefits to the urban water agencies was then determined for thereservoir’s projected supplied water volumes and water values based on the agencies’ estimatedwillingness to pay. The probability of service disruptions from future seismic events to levees andthe expected supply shortages’ magnitudes and durations were derived from the Delta RiskManagement Strategy (DRMS) (DWR, 2009). The emergency water supply availability was based onits averaged annual potential yield (i.e., overall hydrologic year types). The value of suppliedemergency water was based on willingness to pay estimates for water user’s avoidance of waterservice interruptions. The USJI acknowledged that the benefits may be overstated; however, this isthe only approach identified for estimating emergency water benefits associated with storageprojects that has been published to date. Recreation – Recreation benefits were estimated based on unit user day values and visitationprojections. This approach is consistent with the approach used for the Shasta and Upper SanJoaquin investigations. Flood Damage Reduction – Flood damage reduction benefits are based on the decreased incidenceof floods resulting from the construction of the Sites and Golden Gate dams. The value of avoided10

Sites Reservoir Alternatives Evaluationflood damage is based on average crop values, average local structure values, and damage estimatesdeveloped by USACE (USACE, 1999).4.2Operations Modeling ResultsAdditional CALSIM II modeling was performed to evaluate the performance of Alternatives C, D, and E.The model results provide both the average expected yield and the yield during dry/critical periods. Themodeling results (see Table 4) were used to evaluate both the water supply and public benefits for thethree alternatives. The results presented in Table 4 for Alternative C are based on more recent modelingresults than those provided in Attachment 1.11

Sites Reservoir Alternatives EvaluationTable 4. Sites Reservoir Alternatives Performance EvaluationAlternative C (FR, EIR/S)Operationswithout BDCPItemUnitsAverageYearDry orCriticalYearAlternative DIntegratedOperations withBDCP ALT 4 HOSAverageYearDry orCriticalYearOperationswithout BDCPAverageYearDry orCriticalYearAlternative EIntegratedOperations withBDCP ALT 4 HOSAverageYearDry orCriticalYearOperationswithout BDCPAverageYearDry orCriticalYearIntegratedOperations withBDCP ALT 4 HOSAverageYearDry orCriticalYearCapacitiesMaximum Reservoir StorageMAFNumber of IntakesNew Delevan Pipelinecfs1.81.31.83 (TCC, GCC and New Delevan)2 (TCC and GCC)2 (TCC and GCC)2,200 Diversion/1,500 Release1,125 Release1,500 ReleaseFills/System Storage/ReleasesAnnual Diversion from River ncrease in System End-ofSeptember Carryover Storage(Sites, Trinity, Shasta, Oroville,and Folsom 9TAF/yr514624478583400437375397461536407484Annual Water Supply Increase forM&I and Agricultural UseTAF/yr248386232- 344283- 510174280182- 265192- 345210307197- 297234- 415Delta Export Salt Cost (estimatedbased on Delta Export; 18%without, 7% with BDCP)TAF/yr385614- 2117- 31283911- 1713- 22344812- 1915- 27Annual Release from SitesVolume for Water Supply12

Sites Reservoir Alternatives EvaluationAlternative C (FR, EIR/S)Operationswithout BDCPItemUnitsAverageYearAlternative DIntegratedOperations withBDCP ALT 4 HOSDry orCriticalYearAverageYearDry orCriticalYearO

the development of two new alternatives. Table 1 provides a summary of the components of Alternatives A through E. Previous reports by Reclamation (Reclamation, 2013) and DWR (DWR, 2014) provide evaluation results for Alternatives A and B. These alternatives were not further evaluated by the JPA, but are included in Table 1 for completeness.