Feasibility of Fish Passage at Alameda Creek Diversion Dam

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Feasibility of Fish Passage at Alameda Creek Diversion Damdifficulty of debris and sediment maintenance via sluicing. Engineering solutions to potentialsediment issues, however, are feasible.While this configuration would likely be the more expensive to construct, the probability of successwith respect to fish protection and water diversion may be higher than with screening inside thesediment channel. Therefore, this screen configuration is retained for further analysis in thismemorandum.If the existing trash rack and diversion structure were completely demolished, it may be possible toinstall a V-type screen. A side-channel V screen is commonly used for water diversions in Californiaand can comply with regulatory requirements. The bottom point of the V typically points downstream, and fish are collected for bypass from the downstream center of the V. This type ofarrangement would require major modifications of the sediment channel. For example, the channelcould be re-constructed in a manner that would accommodate the V screen within the channel. Onebenefit of this type of arrangement is the potential to fit more screen area into less space, which mayhelp maintain the existing diversion capacity of the ACDT. Another advantage is that the trash rackcan typically be set at the point of diversion, with the screens farther back in the channel, so that thehydraulic influence of the trash rack on the approach velocities at the screens is eliminated. Typicallya standard brush cleaning system is used with V screens, in compliance with NMFS and CDFGregulations. A fish screen bypass would be required, as described above. This type of screenconfiguration at ACDD may require more extensive review from NMFS and CDFG, because it isconsidered off-channel screening and is typically used in canals. It may be appropriate and justifiableat ACDD, however, due to site constraints. If the side channel is considered a canal, a 0.4-foot-persecond (fps) approach velocity may be applicable (CDFG, 2009), thus shortening the required screenlength. Discussion with relevant resource agencies could be conducted to determine suitability atACDD. If approved, the suitability of V screens could be further evaluated during any future screenplanning and design. However, given that such a use is somewhat speculative, V screens are notevaluated further in this memorandum.ACDD Passage June 2009 Page 4-28
5.0 Capital and Operating and Maintenance Costs5 CAPITAL AND OPERATING AND MAINTENANCE COSTSIn the previous section, design components were identified and evaluated based on their ability tomeet the biological requirements of adult steelhead immigration, and screened for suitability atACDD. The design components evaluated in this section were retained for further considerationbecause they are more likely to meet the biological requirements of passage and are considered to begenerally suitable for this location. In cases where multiple variations of a design component couldpotentially be suitable at ACDD, an effort was made to select the design component that appearedmost favorable, based on potential cost, biological suitability, and engineering feasibility, and onlycarry forward that design component. The following design components were retained through thepreliminary analysis, and are evaluated in this section based on cost:■■■Fish ladderTrap and haulFish screensThe estimated cost of fish passage, including screening, is presented in the following sections based oncapital costs of construction (Section 5.1), estimated cost of lost water diversion opportunitiesassociated with fish ladders and screening (Section 5.2), and the total annualized cost of each designcomponent alone and in combinations that together provide complete fish passage options (Section 5.3).5.1 CAPITAL COSTSThe cost of passage and screening design components at the ACDD includes both the capital cost ofconstructing the facilities and annual operations and maintenance costs. This section describes theestimated capital costs associated with the design components retained through the initial analysis.Capital cost estimates are provided based upon facilities at other sites where similar projects have beenimplemented, as well as typical industry costs and engineering judgment. Each design component wasevaluated on a conceptual level, taking into consideration basic factors such as site conditions andconceptual designs. When sufficient information was available, capital costs for the design componentswere estimated by developing unit costs and multiplying these by estimated quantities. Unit costs werecompared with historical database unit prices; vendor quotes were used, when available. Where thelevel of design detail was insufficient to support an estimate, lump sum allowances based on historicalexperience for similar projects were used. Raw capital costs were then generated for each designcomponent. Estimated raw costs and additional assumptions are detailed in Appendix A.As described in Section 4, the Long Fishway and the screen configuration outside of the sedimentchannel have been carried forward in this memorandum. Comprehensive design work has not beendone for any of the design components. For purposes of analysis, relative cost estimates weredeveloped. Raw capital costs presented in Table 5-1 are based on the limited descriptions of thedesign components provided in Section 4 and assumptions regarding the types of materials presentedin Appendix A.The SFPUC Water System Improvement Program (WSIP) program delivery cost methodology(SFPUC, 2006) was used to determine the factor to add to the raw construction cost to develop a totalestimated capital cost for each design component (Table 5-1). The total factor of 100 percent consistsof an estimate contingency (25 percent), construction escalation to time of construction (24 percent),construction contingency (10 percent), and soft costs (e.g., planning, design, review, management, etc.)(41 percent).ACDD Passage June 2009 Page 5-1
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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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Page 8 and 9:
Page 11 and 12: 1.0 Introduction1 INTRODUCTION1.1 B
Page 13: 24Alamo680DanvilleAlameda CreekWate
Page 16 and 17: Feasibility of Fish Passage at Alam
Page 18 and 19: 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 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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