SCH Number 2002031088

Project Info

Title

Viejas Boulevard Bridge Replacement Project (1C8397)

Description

The California Department of Fish and Game is executing a Lake and Streambed Alteration Agreement number 1600-2003-0141-R5 pursuant to Section 1602 of the Fish and Game Code to the project applicant, County of San Diego, Department of Public Works. The applicant proposes to alter the stream to replace the existing bridge where Viejas Boulevard crosses the Sweetwater River. The planned bridge will span 120 feet and be supported by two abutments spaced 125 feet apart. The north abutment will be 14 feet north of the existing abutment and the south abutment will be 26 feet south of the existing abutment. The south side of the Sweetwater River Channel will be widened at the proposed bridge site to accommodate the new position of the abutment and allow for Q100 flood passage. Excavation for lengthening the bridge and channel grading of the streambed upstream and downstream of the bridge to accommodate the 100-year flood will be 4,800 cubic yards. There will be 412 cubic yards of structural backfill and 901 cubic yards of structural concrete for the bridge footing. The deck will be concrete and 45.5 feet wide with two travel lanes, shoulder lanes, and a pedestrian walkway separated by an inboard railing. The planned bridge will be located in the same location and alignment as the existing bridge, with no increase in vehicle capacity. To maintain access across the Sweetwater River during construction, traffic will be rerouted onto a temporary detour road to be constructed east (downstream) of the existing bridge using temporary fill. Three temporary culverts will be installed underneath the detour road to direct stream-flow and to allow for the movement of wildlife through the construction area. The culverts will be 8 feet in diameter with a 3-foot soft bottom sand base. Silt fencing and directional snow fencing will be installed to guide wildlife away from the roadway and through the crossings. The detour road will be removed upon completion of the bridge and the entire construction area will be restored and revegetated to pre-construction conditions. Native riparian habitats found on site include: southern willow scrub, southern coast live oak riparian forest, open water, and floodway.

4 documents in project