Under an on-call contract with Contra Costa County, MGE received a task order to complete the structural evaluation, provide recommendations for repair, and prepare PS&E for two bridges funded under the Bridge Preventive Maintenance Program (BPMP)
The Jersey Island Bridge over Dutch Slough in Oakley, CA was designed and constructed in 1949, and consists of a 32-span, timber girder bridge with a reinforced concrete deck slab and supported on concrete abutments and driven timber pile bents. The overall structure length is 629’-10”. The structure provides two 11-foot traffic lanes between concrete curbs. Bridge modifications in 1967 included removal of bent 9 to allow for a 38-foot span for vessel passage. MGE inspected bridge members to verify needed repair or replacement as noted in the Caltrans Bridge Inspection Report. A thorough visual inspection of the bridge with the use of a kayak confirmed the conditions and identified bridge members in need of repair or replacement.
The Clifton Court Road Bridge over Italian Slough was constructed in 1950, and consists of a 5-span, timber girder bridge with a reinforced concrete deck slab and supported on concrete abutments and driven timber pile bents. The overall structure length is 93’-10”. There is also a timber retaining wall located 4-feet in front of abutment 1 that is not reflected in the “as-built” plans. MGE inspected the bridge to verify and document the current condition of needing repair or replacement. The field inspection consisted of a visual inspection of the bridge. Measurements of the existing timber retaining wall, photographs, and notes were taken to record, document, and verify current conditions and deficiencies.
MGE has completed the design and plans, specifications, and estimates (PS&E) for the recommended repairs to these two-bridges under the BPMP, construction of the repairs is underway.