Comments Period: September 18, 2019 – October 18, 2019
SUBJECT: The U.S. Army Corps of Engineers, Sacramento District, (Corps) is evaluating a permit application to construct the B.F. Sisk Dam Safety of Dams Modification project, which would result in impacts to approximately 9.65 acres of waters of the United States, including wetlands, adjacent to the San Luis Reservoir and O’Neill Forebay. This notice is to inform interested parties of the proposed activity and to solicit comments.
AUTHORITY: This application is being evaluated under Section 404 of the Clean Water Act for the discharge of dredged or fill material in waters of the United States.
APPLICANT: United States Bureau of Reclamation (USBR)
Attn: Mr. Mark Morberg
2800 Cottage Way
Sacramento, California 95825-1846
LOCATION: The approximately 3,905-acre project site is located along the eastern shore of the San Luis Reservoir and the southern shore of O’Neill Forebay, approximately 4 miles northwest of the town of Santa Nella in Merced County, California, Latitude 37.047735°, Longitude -121.060860°, and can be seen on the San Luis Dam USGS Topographic Quadrangle.
PROJECT DESCRIPTION: The applicant is proposing to increase the height of the existing dam embankment to reduce the likelihood of overtopping if slumping were to occur during a seismic event. The applicant believes there is a need to reduce safety concerns of the downstream public and to maintain water supply deliveries. Based on the available information, the overall project purpose is to reduce the risk of a seismic event interrupting water deliveries or flooding downstream properties. As proposed, the USBR would raise the dam crest by twelve feet at the central valley sections of the dam embankment. The raise would taper to the existing crest elevations at the abutments. The project would include adding embankment material, constructing stability berms, and installing downstream crack filters. Additionally, a foundation shear key may be included, depending on the results of pending analyses. The attached drawings provide additional project details.
Environmental Setting. There are approximately 1,136.5 acres of wetlands and other waters of the United States within the project area. These waters include the San Luis Reservoir and adjacent wetlands and streams. The site is located on the west side of the Central Valley in the eastern slopes of the Diablo Range. Average annual precipitation in the area is 10.36 inches.
Alternatives. The applicant has not provided information concerning project alternatives. Additional information concerning project alternatives may be available from the applicant or their agent. Other alternatives will develop during the review process for this permit application. All reasonable project alternatives, in particular those which may be less damaging to the aquatic environment, will be considered.
Mitigation. The Corps requires that applicants consider and use all reasonable and practical measures to avoid and minimize impacts to aquatic resources. If the applicant is unable to avoid or minimize all impacts, the Corps may require compensatory mitigation. The applicant has proposed to mitigate permanent impacts to fresh emergent wetlands, seasonal wetlands, and ephemeral drainages at a 2:1 ratio. The applicant proposes to either purchase credits from a Corps-approved compensatory mitigation bank or establish aquatic resource habitats on-site.
OTHER GOVERNMENTAL AUTHORIZATIONS: Water quality certification or a waiver, as required under Section 401 of the Clean Water Act from the Central Valley Regional Water Quality Control Board is required for this project. The applicant has not indicated they have applied for certification.
HISTORIC PROPERTIES: Based on the available information, potentially eligible cultural resources may be affected by the proposed project. The USBR is the lead federal agency and will, in coordination with the Corps, initiate consultation with the State Historic Preservation Officer under Section 106 of the National Historic Preservation Act, as appropriate.
ENDANGERED SPECIES: The proposed activity may affect Federally-listed endangered or threatened species or their critical habitat. The USBR, as the lead federal agency, will coordinate with the Corps and initiate consultation with the U.S. Fish and Wildlife Service, pursuant to Section 7 of the Endangered Species Act, as appropriate.
ESSENTIAL FISH HABITAT: The proposed project would not adversely affect Essential Fish Habitat (EFH) as defined in the Magnuson-Stevens Fishery Conservation and Management Act.
The above determinations are based on information provided by the applicant and our preliminary review.
EVALUATION FACTORS: The decision whether to issue a permit will be based on an evaluation of the probable impacts, including cumulative impacts, of the described activity on the public interest. That decision will reflect the national concern for both protection and utilization of important resources. The benefit, which reasonably may be expected to accrue from the described activity, must be balanced against its reasonably foreseeable detriments. All factors which may be relevant to the described activity will be considered, including the cumulative effects thereof; among those are conservation, economics, aesthetics, general environmental concerns, wetlands, historic properties, fish and wildlife values, flood hazards, floodplain values, land use, navigation, shoreline erosion and accretion, recreation, water supply and conservation, water quality, energy needs, safety, food and fiber production, mineral needs, consideration of property ownership and, in general, the needs and welfare of the people. The activity's impact on the public interest will include application of the Section 404(b)(1) guidelines promulgated by the Administrator, Environmental Protection Agency (40 CFR Part 230).
The Corps is soliciting comments from the public, Federal, State, and local agencies and officials, Indian tribes, and other interested parties in order to consider and evaluate the impacts of this proposed activity. Any comments received will be considered by the Corps to determine whether to issue, modify, condition, or deny a permit for this proposal. To make this decision, comments are used to assess impacts on endangered species, historic properties, water quality, general environmental effects, and other public interest factors listed above. Comments are used in the preparation of an Environmental Assessment and/or an Environmental Impact Statement pursuant to the National Environmental Policy Act. Comments are also used to determine the need for a public hearing and to determine the overall public interest of the proposed activity.
SUBMITTING COMMENTS: Written comments, referencing Public Notice SPK-2010-00683 must be submitted to the office listed below on or before October 18, 2019.
William Ness, Senior Project Manager
US Army Corps of Engineers, Sacramento District
1325 J Street, Room 1350
Sacramento, California 95814-2922
The Corps is particularly interested in receiving comments related to the proposal's probable impacts on the affected aquatic environment and the secondary and cumulative effects. Anyone may request, in writing, that a public hearing be held to consider this application. Requests shall specifically state, with particularity, the reason(s) for holding a public hearing. If the Corps determines that the information received in response to this notice is inadequate for thorough evaluation, a public hearing may be warranted. If a public hearing is warranted, interested parties will be notified of the time, date, and location. Please note that all comment letters received are subject to release to the public through the Freedom of Information Act. If you have questions or need additional information please contact the applicant or the Corps' project manager, William Ness, at (916) 557-5268, or William.W.Ness@usace.army.mil.
Attachments: 16 drawings