20A - AA FIRST ST BRIDGE REPLACEMENT PROJECT

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LSA ASSOCIATES, INC. INITIAL. STUDY/MITIGATED NEGATIVE DECLARATION JULY 2010 FIRST STREET BRIDGE REPLACEMENT PROJECT CITY OF SANTA ANA The bridge was originally constructed in 1937 and widened in 1959. A seismic retrofit of the bridge was completed in 2005. The existing bridge consists of two structures, a northern structure (westbound lanes) and a southern structure (eastbound lanes). A sidewalk is on the north side, but does not connect with any existing sidewalk on either approach to the bridge. The bridge deck is approximately 420 feet (ft) in length with a width of approximately 60 ft. The bridge accommodates two traffic lanes in each direction. Approaches to the bridge on the east and west sides are six lanes that transition to four lanes within approximately 300 ft of the bridge on both the east and west approaches. First Street intersects the Santa Ana River Bicycle Trail (Bicycle Trail), which is a Class 1 (off-road, paved) regional Bicycle Trail shown on the Bicycleways Master Plan (Orange County Transportation Authority [OCTA]). The Bicycle Trail is grade separated (below First Street) to allow uninterrupted movement of both facilities and to reduce bicycle/vehicle safety hazards. Access ramps to the Bicycle Trail are located on the east side of the bridge. The Bicycle Trail access ramps are located on both the north and south sides of the eastern bridge abutment. The Bicycle Trail is primarily used for recreation, is owned by the Orange County Flood Control District (OCFD), and is operated and maintained by the Orange County Resources and Development Management Department, Harbors, Beaches and Parks Division. 2.3 DEVELOPMENT PROPOSAL The project consists of replacing an existing four-lane bridge to accommodate six lanes and sidewalks. The existing four-lane bridge is the only constraint in the project area for First Street to be built out to its master-planned width of six lanes. Approximately 300 ft east and west of the existing bridge, First Street is a six-lane Major Arterial, as shown on the Orange County Master MPAH and the City's General Plan Circulation Element. The proposed bridge would have the same vertical profile as the existing, but would move the horizontal profile of the roadway centerline by approximately ten feet. The proposed project will be constructed in two phases. Demolition and construction will occur first on the northern bridge structure, followed by demolition and construction of southern bridge structure. This will allow the roadway to remain operational during construction by providing one through-lane in each direction. The new bridge will meet the City's seismic design criteria and will add one lane in each direction and a sidewalk on the north and south sides of the bridge. The proposed project would restripe areas 300 feet east and west of the bridge structure to accommodate an additional travel lane in this area. Refer to Figures 8a, 8b and 9 for the Bridge Plans, Bridge Sections and Restriping Plan. Right-Of-Way Requirements and Access The City has already obtained necessary rights-of-way for the bridge replacement and roadway widening. One easement over the Santa Ana River will need to be obtained by the City. A temporary construction easement will be required. Access to the project will be accomplished through existing access via First Street, the OCFCD maintenance road on the west side of the Santa Ana River, and the Santa Ana River Bicycle Trail on the east side of the Santa Ana River. PADMJ0701\MND\2.0 Project Description.doc (07/25/10) 2-9 20A-20