Feasibility of Fish Passage at Alameda Creek Diversion Dam

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Feasibility of Fish Passage at Alameda Creek Diversion Damlikely suggest that less water is diverted annually through the ACDT than estimated in thisanalysis (Table 5-2, third column). A preliminary analysis suggests that during the wettestmonths of a wet year the use of daily average data may overestimate diversion rates byapproximately 6 percent, compared to estimates based on 15-minute interval data. During mostflow conditions (dry, low, normal) there would be no difference in the diversion rate estimatedusing daily average data or 15-minute interval data, so the actual margin of error due to the use ofdaily average data is expected to be less than 6 percent.■■■■■Potential diversion volumes calculated for both unimpaired diversions and diversion withscreening represent the maximum amount of water that could have been diverted under idealconditions. In application, actual flows to ACDT could be intermittently influenced by debrisjam and other features present in real time conditions.Calaveras Reservoir, prior to the Division of Safety of Dams (DSOD) restriction, periodicallyfilled to capacity and spilled. During years when the reservoir spills, there is a lack of capacity inCalaveras Reservoir to store water that could be potentially diverted from ACDD. Since theconceptual level feasibility analysis in this memorandum does not include development of asystems model to integrate historic spill scenarios, water year types, and the lost water diversionestimates in Section 5.2, the net effect of spills is not assessed in this analysis of lost waterdiversion costs.The water cost analysis is based on the assumption that the SFPUC-proposed normal water yearinstream flows, including WSIP Final PEIR mitigation flows, would be bypassed at the ACDDwhen available. The SFPUC-proposed instream flows, however, include three different flowschedules to be alternately implemented depending on the annual hydrological conditions (dry,normal, and wet) (Section 2.3.2.2). A preliminary review indicated that lost water costs atACDD, while implementing screens, a fishway, and the normal water year flow schedule,produced results generally comparable to those that included the other flow schedules (dry andwet). Therefore use of the normal water year flow schedule was assumed to be appropriate forthe level of analysis in this conceptual feasibility study.Because it is based on the flows predicted by the model described in Appendix B, the water costestimate is limited by the accuracy of the model. Any inaccuracies inherent in the modeled flowsare propagated to this water cost estimate.For the purposes of this analysis, and consistent with SFPUC’s commitment to maximizingaquatic habitat under future CDRP operations (SFPUC, 2008a), it is assumed that the SFPUCproposedflows (SFPUC, 2009b) are preferentially provided as bypass flows at ACDD whenevernatural flows are present.5.3 ANNUALIZED CAPITAL AND OPERATIONS ANDMAINTENANCE COSTSIn this section, capital costs developed in Section 5.1 are annualized and combined with annual watercosts developed in Section 5.2 and operations and maintenance costs (developed in this section) toestimate the total annualized cost of fish passage design components at ACDD. The designcomponents are also combined to show the total estimated annualized cost of complete fish passageoptions at ACDD. The purpose of the preliminary cost assessment is to characterize annualized costsfor design components related to fish passage that have been retained up to this point for furtherACDD Passage June 2009 Page 5-10
5.0 Capital and Operating and Maintenance Costsconsideration in this technical memorandum. The cost estimates are not as detailed as those thatwould be used for fiscal planning or bid solicitation, but can be used to compare the relative costamong fish passage design components.Table 5-3 presents the estimated total annualized cost of each design component, includingannualized capital costs, operations and maintenance, and associated water costs. In order toaccurately compare the design component costs on an annual level, a Capital Recovery Factor (CRF)was used to convert each total capital cost into a series of equal annual costs (Cal/EPA, 1996). It isassumed that the capital costs are paid over a 30-year period at an interest rate of 5.5 percent,resulting in a CRF of 0.0688 (Table 5-3).Order-of-magnitude operations and maintenance cost estimates were developed as part of this initialassessment of passage and screening design components (Annual O&M Allowance, Table 5-3).These estimates, detailed in Appendix A, include 0.5 percent of the total capital cost for generalmaintenance, as well as labor and other costs that would likely be required to operate the designcomponents.Annual water costs due to reduced diversion capacity with fish screens, fish screen bypass flows, andfish ladder operation flows are included as an operating cost that will be incurred each year that thefacility is in operation. Hence, water costs were added to the annualized cost for design componentsthat would incur such costs (Table 5-3). The total annualized screen and fishway costs include theannual lost water diversion opportunity costs that were developed in Section 5.2.Table 5-3ACDD Fish Passage Design Components Annualized CostsDesign ComponentTotalCapital CostAnnualizedCapital Cost 1Annual O&MAllowance 2Annual WaterCosts 3Total AnnualizedCostLong Fishway $10,502,000 $723,000 $114,000 $195,000 $1,032,000Confluence Fish Facility $1,606,000 $111,000 $74,000 N/A $185,000Camp Ohlone Haul Route $6,540,000 $450,000 $33,000 N/A $483,000Fish Screens $13,220,000 $910,000 $135,000 $2,265,000 $3,310,000Notes:1The annualized capital cost assumes a Capital Recovery Factor (Cal/EPA, 1996) of 0.0688, assuming 5.5% interest over30 years.2Cost estimate presented in Appendix A, Table A-2.3Water costs include lost water diversion opportunity costs developed in Sections 5.1 and 5.2.N/A = not applicableIn Table 5-4, design components are grouped together to identify options that provide both passageand screening (in other words, “options” are combinations of components that create complete fishpassage). For example, the Ohlone Trap and Haul option would include trapping immigrating adultsat the Confluence Fish Facility, hauling them upstream via the Camp Ohlone Haul Route, andreleasing them above ACDD, as well as screening at ACDT.ACDD Passage June 2009 Page 5-11
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T E C H N I C A L M E M O R A N D U
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Feasibility of Fish Passage at Alam
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1.0 Introduction1 INTRODUCTION1.1 B
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24Alamo680DanvilleAlameda CreekWate
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oleyriesSanCalaveras Creekalaveras
Page 20 and 21: (a)(b)Alameda Creek Diversion Dam (
Page 23 and 24: 2.0 Setting2.3.2.1 ALAMEDA CREEK DI
Page 25 and 26: 2.0 Settingalmost never submerged;
Page 27 and 28: 2.0 SettingRainbow trout are the sa
Page 29: 2.0 SettingA number of future proje
Page 32 and 33: Feasibility of Fish Passage at Alam
Page 42 and 43: (a) A view of the navigation lock a
Page 44 and 45: (a) A pickup truck adapted for haul
Page 57: Approximately 1.8 miles toCalaveras
Page 77 and 78: 6.0 Additional Considerations and A
Page 79: 6.0 Additional Considerations and A
Page 89 and 90: 9.0 Report Preparation9 REPORT PREP
Page 91 and 92: 10.0 References10 REFERENCESAACE (A
Page 93 and 94: 10.0 ReferencesHayes, Darrel, 2001.
Page 95 and 96: 10.0 ReferencesSak, B., San Francis
Page 97: 10.0 ReferencesWDFW (Washington Dep
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Feasibility of Fish Passage at Alameda Creek Diversion Dam

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