Drainage Area 48B - Line A Improvement Project

Drainage Area 48B - Line A Improvement Project

The Flood Control District proposes to replace and upgrade approximately 660 feet of existing pipe and excavation up to approximately 500 feet to 1,000 feet segment of earth ditch in Line A of Drainage Area 48B in the Bay Point Area of East Contra Costa County. The existing 66-inch corrugated metal pipe (CMP) pipe, in the vicinity of Skipper Lane and Port Chicago Highway, runs west to east from an earth channel behind a local shopping center, to the Port Chicago Highway right-of-way where it turns north and across the road where it discharges into an existing earth channel. An internal field review of the pipe showed extensive corrosion in the invert of the pipe throughout, with the upper portion being the worst area. The replacement pipe will be up to an 84-inch reinforced concrete pipe (RCP) or spiral ribbed pipe. The pipe will be constructed deeper than the existing 66-inch line to avoid utility conflicts and will terminate at the existing natural channel at a lower flow line. This will necessitate excavating the channel to a point up to approximately 500 to 1,000 feet downstream. The channel may be widened to the south of the existing channel elevation and be up to 45 inches deeper than the existing channel where the new pipe outfalls into the channel. The new reach of the channel will be hydroseeded and revegetated with native trees and wetland vegetation as part of the project. The existing segment of the drainage ditch will be back-filled. If feasible, a portion of the earth channel may be realigned to run parallel with the property line. The project may be done in phases, over a two-year period.

Contra Costa

California Department of Fish and Wildlife, Bay Delta Region 3 (CDFW), California Department of Health Care Services (DHCS), California Department of Parks and Recreation, California Native American Heritage Commission (NAHC), California State Lands Commission (SLC), Central Valley Flood Protection Board, Delta Protection Commission, Department of Water Resources, Resources Agency, State Water Resources Control Board, Division of Water Quality, State Water Resources Control Board, Divison of Financial Assistance, California Department of Transportation, District 4 (DOT), California Regional Water Quality Control Board, Central Valley Sacramento Region 5 (RWQCB)

California Department of Transportation, District 4 (DOT), California Regional Water Quality Control Board, Central Valley Sacramento Region 5 (RWQCB)

Other (Drainage Improvement)

Drainage Improvement