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4.2.2 Cumulative Effects 4.2.2.1 Effects on the Physical Environment Like other screening projects, the RD 108 Proposed Project would have permanent effects associated with a larger diversion facility along the banks of the Sacramento River. It is reasonable to assume that, in the long term, most if not all of the large agricultural diversions along the river and in the Delta would be upgraded in a similar manner, and that this upgrade would mean that a concrete structure would replace the riprapped and earthen, predominantly unvegetated levee slopes below mean high water. The cumulative effect of this replacement on physical habitat would be small. The construction of the new Combined Pumping Plant and associated new canals would eliminate 4.4 acres of non-native grass and shrub habitat along the eastern (river side) edge of the Sacramento River Levee and about 28 additional acres of agricultural area along the base of the existing levee. The project would only temporarily remove about 6 acres of land from a wheat field along Highway 45 and the alignment from Highway 45 to the Combined Pumping Plant/Fish Screen. These losses of disturbed habitats would run somewhat counter to the trend towards conversion of agricultural and flood bypass areas to wildlife habitat. The removal of three existing diversions/pumping plants from the Sacramento River and their consolidation at a single site would contribute to the general trend towards such consolidations, and would contribute to the cumulative reduction in such sites. 4.2.2.2 Effects of Operating Screens, Diversions, and Canals The operation of the fish screen would not change diversions or flows or the timing of diversions or flows in the irrigation channels and would not directly affect the habitat of any terrestrial special-status species within the USGS Kirkwood Quadrangle. Routine maintenance would not adversely affect important wildlife habitat or adversely affect special-status terrestrial or avian species. Assuming (worst case) that about 25 similar screening facilities approximately 500 feet (150 meters) in length would be installed within the 400 miles of riverbank from Red Bluff to the Delta, and that the associated construction would impact areas not already riprapped, habitat losses would be about 0.5%. Given that many screening locations would already be riprapped or lacking in substantial submerged aquatic or emergent aquatic vegetation, a lower level of actual cumulative habitat loss would be anticipated. Additionally, this potential cumulative loss of less than 0.5% of the existing riverbank habitat would be further reduced as a result of implementing CALFED ERP and CVPIA efforts to restore significant functional riverine habitat in the Sacramento River system. Construction of fish screen projects may, however, limit CALFED ERP options in developing feasible set back levees on selected reaches of the Sacramento River. This could occur due to the large capital costs of fish screen projects, thereby creating fixed points on the river that will not be moved in the near future. The effects of existing and future fish screen projects on setback levees and associated benefits from setback levee enhanced riverine habitat is unknown and cannot be quantified at this time. In addition, the construction-related effects of the project would not have significant effects on the physical environment because (a) these effects are temporary and (b) the overall program for rehabilitating screens and habitat in the Sacramento River would occur over a period of many years, and it is unlikely that more than one or two similar project would occur in any given year. These projects, taken collectively, would therefore have effects on only a small reach of the river system in any given year. The boat ramp and weir bridge construction project would occur in an area that currently consists of a bridge and riprapped levee slope. In addition, the closure and removal of the existing boat ramp 12 miles upstream will, from a cumulative effects perspective, offset any impacts associated with this boat ramp (which is not a part of the Proposed Project). No net habitat for fish or wildlife would therefore be lost. If CALFED continues its program to restore connectivity between the river and its floodplain, which is generally accomplished via set-back levees, the construction of a number of similar facilities would have a negligible effect on flooding in the Sacramento Basin. This conclusion assumes that cooperative efforts to screen water diversions will result in siting of such diversions in a manner that would not significantly constrain the CALFED Ecosystem Restoration program. The consolidation of three existing facilities into a single facility would reduce the number of in-channel facilities which must be protected during CALFED Ecosystem Restoration planning. Setback levees across the river from Boyers Bend, Howells Landing, and Tyndall Mound, which might not have been feasible without the Proposed Project, may now be feasible. To this extent, the Proposed Project contributes to the trend towards use of setback levees to enhance the connection between the river and its floodplain. The volumes of water diverted at the Combined Pumping Plant/Fish Screen after construction would be comparable to the existing baseline conditions and therefore no affects on Sacramento River flows are anticipated that would affect quality and availability of habitat for protected fish species. 4.2.2.3 Effects on Winter-run Chinook and Winter-run Chinook Critical Habitat; Spring-run Chinook Salmon; Steelhead; Fall-run/Late Fall-run Chinook salmon, Proposed Spring-run Chinook Salmon and Steelhead Critical Habitat, and Essential Fish Habitat for Pacific Salmon During construction, the increased loss of juvenile fish by entrainment will contribute to the overall mortality experienced by rearing and emigrating juvenile fish throughout the Sacramento River system. This is an adverse cumulative effect of the project. Given that up to 100,000,000 juvenile salmon may emigrate within the Sacramento-San Joaquin River system in any given year, the incremental contribution of this construction effect to overall mortality is unlikely to be great. There may, however, be increased incidental take of individuals of the threatened and endangered runs of salmonids. While this take is not possible to quantify, it should be considered a potential cumulative effect of the project. It should be noted that the project is scheduled to be constructed during a period when ocean conditions have been favorable for salmonids and the number of returning adults has increased significantly when compared to returns for the period 1970-1990. Construction of the project (and associated adverse effects) is thus optimally timed for minimizing the population level cumulative effects. The Proposed Project will also have long-term and beneficial cumulative effects on this same suite of salmonids. In the context of other fish screening projects, as well as CALFED efforts to enhance riverine habitat conditions (such as with revegetation and set-back of levees) the Proposed Project would contribute to an incremental cumulative biological benefit of these restoration and recovery efforts. The consolidated fish screen would substantially reduce or avoid entrainment mortality for protected fish species resulting from operation of the currently unscreened diversions. The reduction in entrainment mortality would complement and enhance cumulative efforts within the watershed to improve habitat conditions and reduce mortality for protected fish and other biological resources within the Sacramento River. Construction and operation of the Combined Pumping Plant/Fish Screen would not be expected to contribute directly or indirectly to long-term adverse effects on fishery habitat within the river but would provide substantial benefits through a reduction in the vulnerability of salmonids and other fish species to entrainment mortality at the existing unscreened facilities. Construction-related activity such as short-term localized increases in suspended sediment concentrations with the Sacramento River during cofferdam installation and site preparation, the temporary increase in vulnerability of juvenile salmonids to stranding during fish screen construction would be so minor that they would not contribute to cumulative impacts on salmonids. Based on results of these analyses it was concluded that the proposed fish screen project would not likely result in adverse cumulative affects on winter-run or spring-run Chinook salmon, winter-run Chinook salmon critical habitat, Central Valley steelhead, or EFH for Pacific salmon. The Proposed Project would contribute to the cumulative biological benefits of ongoing habitat enhancement projects, and efforts to reduce fish mortality, and contribute to the recovery of protected fish species inhabiting the Sacramento River. The Proposed Project would not contribute to an increase in incremental or cumulative affects of diversion operations on instream flow or the associated habitat quality or availability for protected fish, critical habitat for winter-run Chinook salmon, and EFH for Pacific salmon within the Sacramento River. Construction of the fish screen would result in short-term temporary and localized changes in suspended sediment concentrations and turbidity within the river, however these small scale changes are not expected to contribute to incremental or cumulative water quality effects since construction activity would be conducted in compliance with water quality criteria and approvals issued by the Central Valley RWQCB and other resource and regulatory agencies. Analysis indicates that project effects on water quality will be substantially below maximum allowable levels established by the RWQCB and would not approach levels that have been documented to have adverse effects on salmonids. 4.2.2.4 Non-Salmonid Fish Species The cumulative effects of construction of the Proposed Project, combined with other Proposed Projects in the area, are related to minor increases in turbidity in the vicinity of the project, over the long term. The fish screen is designed and will be operated and maintained in a manner that will avoid other types of impacts to fish species, such as discharges of fuels and oils. In this context, the upstream boat ramp north of the Tisdale Bypass will involve unloading and loading of boats, which will often cause resuspension of sediments in the immediate vicinity of the ramp. This resuspension will be localized, but may result in deposition of re-suspended sand and silt for up to a few hundred feet downstream. Given the potential for variable flows in the river to scour and re-suspend sediments in this reach of a leveed river, this cumulative effect represents a small fraction of the total potential for sediment transport and resuspension in this reach. In addition, turbidity related to boat use in a riverine environment is primarily a function of wake effects on unprotected shorelines; entry and removal of boats contributes little to the overall sedimentation/turbidity regime. The net turbidity impact on the river from boat ramp operation will be unchanged, because the existing boat ramp will be permanently abandoned. No increase in boat traffic is anticipated. No increase in boat ramp use in this reach of the river is projected. Localized turbidity impacts are therefore being transferred from one disturbed site to another. 4.2.2.5 Swainson’s Hawk The project itself has the potential for temporary adverse effects on Swainson's hawks, but incorporating the conservations measures into project activities should minimize these effects. In the context of the CALFED ERP goal of restoring and enhancing substantial areas of riparian habitat along the Sacramento River and its tributaries, no cumulative effects are anticipated as a result of this project. Construction effects on Swainson's hawks could combine with the effects of the proposed boat ramp relocation to result in a higher level of noise disturbance for nesting hawks over an extended period of time. The relocation of the boat ramp will also, however, mean that boaters who currently drive past nest sites at the junction of the Sacramento River and the Tisdale Bypass will be diverted away from this site to the new (southerly) site. A reduction in driving impacts associated with boaters driving from Sacramento area locations to the existing boat ramp 12 miles north of the proposed new boat ramp would be expected. All of this traffic will occur on the eastern side of the Sacramento River, and there is virtually no local traffic connectivity between the East and West areas. Boating within the mainstem Sacramento River would not be expected to increase as a result of the project. The cumulative effects of the boat ramp and construction may therefore be considered to be a transfer of noise and visual disturbance from one site to another. 4.2.2.6 Giant Garter Snake The project itself has very limited potential for adverse effects on the giant garter snake, and the potential for direct effects is limited to a possible effect on the individuals during use of Borrow Site 2. Over the long-term, the project does not affect available habitat or the access of the giant garter snake to this habitat. Because the project has no additive effects on habitat or populations of the giant garter snake, the project thus does not contribute to a cumulative trend toward either loss or restoration of habitat for the giant garter snake. In the long-term, the traffic associated with the project in an area of very low traffic volumes and few traffic linkages across the river or the Colusa Basin Drainage Canal, is unlikely to contribute to any trend in traffic in the region that would adversely affect garter snake movement. 4.2.2.7 Valley Elderberry Longhorn Beetle The Proposed Project will not contribute to cumulative effects on valley elderberry longhorn beetle, either positive or negative, because it will not adversely affect habitat nor create habitat for this species. 4.2.2.8 Northwestern Pond Turtle The project itself has very limited potential for adverse effects on the northwestern pond turtle, and the potential for direct effects is limited to a possible effect during use of Borrow Site 2. Over the long-term, the project does not affect available habitat or the access of the northwestern pond turtle to this highly disturbed habitat. The project thus does not contribute to a cumulative trend toward loss or restoration of habitat for the species. In the long-term, the traffic associated with the project in an area of very low traffic volumes and few traffic linkages across the river or the Colusa Basin Drainage Canal, is unlikely to contribute to any trend in traffic in the region that would affect pond turtle movement. 4.2.2.9 Construction and Operation Effects on Air Quality, Water Quality, Aesthetics, Cultural Resources, Land Use, Traffic, Noise, Recreation, Public Services, Hazards and Hazardous Materials, Navigation, Public Safety, and Utilities. The Proposed Project has less-than-significant effects on these aspects of the human environment and they are transient in nature. For example, the Proposed Project will replace three existing diversions with a single diversion, thus reducing activity, noise and disturbance in areas with (sparse) human development. The Proposed Project's minor effects in these categories do not contribute to any long-term trends in the region. 4.3 No Action Alternative The No-Action Alternative would contribute to the long-term trend of loss of fish and wildlife resource values in the Sacramento River Basin. 5.0 CoNSULTATION AND COORDINATION As a consequence of both State and Federal participation in the project, environmental documentation will need to comply with the National Environmental Policy Act (NEPA), the California Environmental Quality Act (CEQA) and both the State and Federal Endangered Species Acts. RD108 is serving as lead agency for CEQA compliance and is a Central Valley Project (CVP) water contractor. The Proposed Project will need to receive the following permits and approvals:
In support of the required permits and consultations, available data has been compiled and analyzed from fishery studies performed at the RD 108 Wilkins Slough diversion facility (Demko et al. 1994; Hanson 1996; Hanson and Bemis 1997) and by CDFG at a downstream sampling location at Knights Landing (Snider and Titus 1998, 2001). Results of these fishery studies provide representative information regarding the seasonal occurrence of various fish species in the Sacramento River in the area of the Proposed Project. Site-specific biological surveys were also conducted in and adjacent to the Action Area by Miriam Green Associates to assess potential impacts of intake construction on plant and wildlife species in the area. Using data from these biological surveys, an ASIP has been prepared for the proposed fish screening project (Hanson and Green 2004) which will be provided to the USFWS, NOAA Fisheries, and CDFG in support of consultation with respect to potential impacts to species protected under the California and Federal ESAs or identified as species of special concern. The ASIP also considers the potential effects of the proposed project on EFH for Pacific salmon. Results and findings of the ASIP have been integrated into this Environmental Assessment/Initial Study. 5.1 Federal Agencies Consulted The following agencies and individuals were contacted as part of the development of the proposed positive barrier fish screen project and/or provided information used in this EA/IS: 5.1.1 U.S. Fish and Wildlife Service (USFWS) The USFWS has been an active participant in the CVPIA Anadromous Fish Screen Program Technical Team, and have provided review and comment on the Proposed Project feasibility analyses and intake structure engineering design. An ASIP has been prepared for the proposed project for review and evaluation by USFWS. USFWS reviewed and provided informal comments and suggestions on an early draft of the ASIP under the authority of the Fish and Wildlife Coordination Act. USFWS will be asked by USBR to concur with findings of the ASIP regarding the potential of the fish screen project to adversely affect protected fish and wildlife. 5.1.2 National Marine Fisheries Service (NOAA Fisheries) NOAA Fisheries has been an active participant in the CVPIA Anadromous Fish Screen Technical Committee, and has provided review and comment on the Proposed Project feasibility analyses and intake structure engineering design. An ASIP has been prepared for the proposed project for review and evaluation by NOAA Fisheries. NOAA Fisheries reviewed and provided informal comments on an early draft of the ASIP. NOAA Fisheries will be asked by USBR to concur with findings of the ASIP regarding the potential of the fish screen project to adversely affect protected fish. 5.1.3 U.S. Army Corps of Engineers An application for a U.S. Department of the Army permit pursuant to Section 10 of the Rivers and Harbors Act, and Section 404 of the Clean Water Act, has been submitted to the Corps Sacramento Office. All terms and conditions of the Corps permit would be implemented. 5.2 State Agencies Consulted 5.2.1 California Department of Fish and Game (CDFG) CDFG has been an active participant in the CVPIA Anadromous Fish Screen Technical Committee, and has provided review and comment on the Proposed Project feasibility analyses and intake structure engineering design. An application for a CDFG Streambed Alteration Agreement, pursuant to Section 1601 of the Fish and Game Code of California, was submitted and has been approved for the proposed project. A copy of the draft Initial Study was provided in support of the Section 1601 permit application. All terms and conditions contained in this agreement would be implemented. The fish screen design and construction would comply with the currently accepted CDFG and NOAA Fisheries Fish Screen Design Criteria. 5.2.2 State Reclamation Board An application has been submitted to the State Reclamation Board for an encroachment permit for the proposed fish screen project. A copy of the draft EA/IS was provided in support of the Reclamation Board permit application. 5.2.3 Regional Water Quality Control Board - Central Valley Region The contractor selected to construct the proposed fish screen would be required to prepare and Erosion Control Plan in order to comply with the water quality objectives established for sediment loading and turbidity. A Clean Water Act Section 401 water quality certification, or waiver thereof, would be obtained for the Corps permit compliance, or other permits or authorizations. An application for a Regional Water Quality Control Board (RWQCB) 404 certification or waiver has been submitted. A copy of the draft EA/IS, application for a CDFG Streambed Alteration Agreement, and Corps permit application were submitted to the in support of the water quality certification. 5.2.4 State Lands Commission An application to the State Lands Commission for the proposed project has been submitted. A copy of the draft Initial Study was submitted in support of the State Lands Commission application. 5.3 Local Agencies Consulted 5.3.1 Yolo and Colusa County air pollution control districts As a preliminary measure, the regulations of the Yolo and Colusa county air pollution control districts were reviewed. Based on this review, appropriate air pollution control measures were included in the Proposed Project description. Prior to construction, these measures will be updated to reflect on-going discussions with these agencies. 5.4 Fish and Wildlife Coordination Act Whenever the waters of any stream or other body of water are proposed or authorized to be impounded, diverted, or otherwise controlled for any purpose whatever, by any Federal department or agency, or by any public or private agency under Federal permit or license, such department or agency would consult with the USFWS to view the conservation of wildlife resources by preventing loss of, or damage to, such resources. The proposed project has complied with the Fish and Wildlife Coordination Act through the Central Valley Project Improvement Act (CVPIA) Anadromous Fish Screen Program (AFSP). This is demonstrated in the role of the USFWS, NOAA Fisheries, USBR, and CDFG in participating in the technical review and comment on the feasibility assessment and fish screen engineering design, review and comment on preliminary engineering designs and design criteria for the proposed project, and participation in review of the draft ASIP and draft EA under the authority of the Fish And Wildlife Coordination Act. USBR is serving as the lead Federal agency for NEPA compliance, and the role of other agencies in the review of this NEPA document has insured equal consideration of fish and wildlife resources. The interdisciplinary involvement within the USBR, NOAA Fisheries, USFWS, CDFG, and the Corps has fulfilled the consultation requirements under the Fish and Wildlife Coordination Act. |