Rossi Bridge Repair RDS25-25

The proposed fix involves removing the impoundment and concrete box culvert and clear spanning Conn Creek. Permits have been applied for with CDFW, RWQCB and the Army Corp however they may not be processed in time to remove the impoundment this coming winter. The County hopes to acquire permits this year so the impoundment can be removed before it fails and pollutes the creek but at a minimum plan to drill 3-36" holes beyond each top of bank and construct the concrete abutments this year while staying outside of top of bank and if needed complete remaining work in the channel once permits are received. Working in the channel will require dewatering and it is anticipated that material will be removed from the roadway by an excavator as it retreats. The channel will be blended to match the geometry just beyond the up and downstream faces of the impoundment. This area will be replanted and monitored after project completion. The final stage of the project will involve launching a prefabricated steel truss bridge across the roadway and paving new approaches to the bridge. The project area encompasses approximately 1.72 acres which includes the Rossi Road Bridge over Conn Creek as well as adjacent private lands, which are primarily agricultural and vineyard properties. The project site and surrounding area is primarily riparian vegetation as well as some vineyards. Best Management Practices and erosion control measures will be implemented, as well as environmental commitments noted in the Biological Report to protect environmental resources, including any potential special-status species or cultural resources that may occur in the proposed area of work. The County is actively working with the United State Army Corp of Engineers to obtain the necessary 404 permit, as well as with the California Department of Fish and Wildlife on the necessary 1602 permit, and the California State Water Resources Control Board for the necessary 401 permit.