Replacement of the Fallon Creek Bridge

Replacement of the Fallon Creek Bridge

The project involves the annual construction and removal of a seasonal, low-water crossing of the San Benito River at Nash Road. The project has been undertaken yearly since the loss of a permanent roadway structure in 1993, and the County seeks to continue the practice until a permanent crossing can be constructed. At the end of the seasonal heavy rainfall period (normally around April 15), County work forces construct an earthen roadbed, with base rock surface and metal culvert, within the San Benito River channel. Later, before the start of heavy winter rains (around December 15th), the roadbed and culvert are removed, and the river channel is restored to its previous condition. Equipment is used to move the earthen material into and out of the stream channel during construction and removal activities. No concrete is involved in the roadbed construction and no roadway material is taken from areas covered by flowing or standing water. No trees or aquatic vegetation are removed. The seasonal roadbed measures approximately 350 feet long and seven (7) feet high. The width of the temporary roadway structure varies from 30 feet at the top to approximately 60 feet at the bottom, with a side slope ratio of 2 to 1. Approximately 1500 cubic yards of material are used to construct the roadway. The five-foot diameter steel culvert, approximately 60 feet in length, is installed to allow low-flow water levels to pass under the roadbed. The culvert is positioned below grade four to six inches. During the rainy season, the earthen material and associated culvert is pushed up out of the channel and piled for storage on an upper terrace, above floddstage. Silt fences are installed to prevent fines from washing into the river.

Tres Pinos

San Benito

California Department of Conservation (DOC), California Department of Parks and Recreation, California Department of Transportation, District 5 (DOT), California Highway Patrol, California Native American Heritage Commission (NAHC), California Regional Water Quality Control Board, Central Coast Region 3 (RWQCB), California State Lands Commission (SLC), Department of Water Resources, Office of Historic Preservation, Resources Agency, State Water Resources Control Board, Division of Water Rights, California Department of Fish and Wildlife, Bay Delta Region 3 (CDFW)

California Department of Fish and Wildlife, Bay Delta Region 3 (CDFW)

Transportation:Other (seasonal stream crossing)

Public Works

Air Quality, Drainage/Absorption, Flood Plain/Flooding, Transportation