Napa River Outfall Project (Notification of Lake or Streambed Alteration, No. EPIMS-NAP-39279-R3)

Napa River Outfall Project (Notification of Lake or Streambed Alteration, No. EPIMS-NAP-39279-R3)

The California Department of Fish and Wildlife has executed Lake and Streambed Alteration Agreement EPIMS Notification No. EPIMS-NAP-39279-R3, pursuant to Section 1602 of the Fish and Game Code to Napa Sanitation District. The project is limited to the removal of two existing outfall structures (Outfall 1 and Outfall 3) along the Napa River, which are no longer in service and have been abandoned. Outfall 1 consists of three separate diffuser pipes, which sit on the bottom of the Napa River and will be removed by cutting the pipes as close to the shore as possible and lifting them out of the river with a crane to avoid the need for excavation. Outfall 3 is located above the waterline and will be removed without the need for in-water work. The project also includes the replacement of tide gates on an existing stormwater outfall to remain in place, which will not result in impacts to habitat. The project will result in a temporary impact to saltmarsh habitat of approximately 256 square feet from the removal of existing Outfall 3 structures and associated riprap and temporary impact to open water habitat of approximately 938 square feet during removal of existing Outfall 1. The removal of these structures and riprap will provide a net reduction in permanent impacts of approximately 344 square feet. Silt curtains will be installed prior to removal of Outlet 1 to prevent water quality impacts outside of the work site. Two riparian trees may need to be removed as part of this project. Access and staging will occur along paved roads adjacent to the work areas and in paved areas set back from the Napa River.

Napa

San Francisco Bay Area

Napa