Rainbow approves water main improvement for Live Oak Park Bridge project

Joe Naiman

Village News Reporter

The County of San Diego will be replacing the Live Oak Park Road bridge, which will impact two Rainbow Municipal Water District water mains. Hazard Construction was given the county contract for the bridge replacement and, on April 26, the Rainbow board approved an agreement with Hazard to add the water main construction to the Lakeside company’s work.

The board’s 5-0 vote approves a construction agreement with Hazard Construction for $507,700, approves additional appropriations of $550,000 for the water main improvement project, and determined that the county’s environmental Mitigated Negative Declaration and that document’s mitigation measures satisfy California Environmental Quality Act requirements for the water main work.

Live Oak Park Bridge is on Live Oak Park Road and crosses the San Luis Rey tributary 160 feet south of Gum Tree Lane. The bridge was constructed in the 1950s by placing three corrugated metal arched culverts side by side in the streambed and connecting them together with Portland cement concrete headwall and endwall composition.

Past inspections of Live Oak Park Bridge revealed a vertical deflection of 1 1/2 feet. Water leaking from one culvert to another was also observed. The deficiencies found included distorted and corroded pipes, bent and crushed pipe sections, pipe deflection, and pipe section loss. Bridge flooding concerns were also noted, as reviews of the bridge determined that the existing metal culverts would not be able to accommodate a 100-year flood event, and the driver sight distance was deemed to be inadequate.

The existing 25 foot long triple arch culvert bridge will be replaced by a concrete slab bridge approximately 58 feet in length with the ability to handle large storms. The project will also improve the alignment and sight distance for that portion of Live Oak Park Road. The road elevation will be raised between three and four feet and the existing corrugated metal pipe culverts underneath the roadway will be removed.

The work will create utility conflicts with San Diego Gas & Electric power lines, AT&T telephone lines, and Rainbow Municipal Water District water pipes. The elevations and alignments of Rainbow’s 8-inch and 16-inch water mains need to be modified. The county has prior rights along Live Oak Park Road, which means that Rainbow is responsible for the water main relocation. The county’s Department of Public Works agreed to construct pipe supports along the sides of the new bridge so that Rainbow can attach the water mains.

In December 2021, the county awarded the Live Oak Park Road Bridge replacement contract to Hazard Construction. Rainbow requested a change order for Hazard to perform the water main relocation in conjunction with the project and the district reimbursing the county for the work, but the county declined that request due to change order limits in the state Public Contract Code. The county did, however, express willingness for Rainbow to have Hazard perform the water main relocation under a district-initiated contract.

The county issued Hazard a Notice to Proceed in March 2022. That month, Rainbow met with Hazard Construction to discuss plans and specifications and requested a bid for the water main relocations. Rainbow’s legal staff determined that competitively bidding the water main portion would not provide any advantage and could create conflicts between contractors if the work was not closely coordinated.

Rainbow staff cut and capped the existing 8-inch and 16-inch mains although district crews would not be able to provide further assistance due to prior commitments on other Rainbow tasks. Rainbow had budgeted $480,000 for the project, although $430,000 of that was earmarked for fiscal year 2022-23. That left $50,000 of 2021-22 budget for Rainbow staff labor, permitting, finalizing project plans, and advertising the project for bid.

The original plan was to budget another $120,000 for fiscal year 2022-23 to bring the total amount to $600,000. That will include $50,770 for contingency and $41,530 for district staff time.