SCW given contract for North River Road sewer repairs

SCW Contracting Corporation was awarded the Rainbow Municipal Water District contract for the first phase of the North River Road Land Outfall pipeline repairs.

The July 28 Rainbow board meeting included a 5-0 vote to award the work to SCW, which is based in the town of Rainbow. The contract will be for $474,000.

“It’s the same contractor who did the previous work for us,” Tom Kennedy, general manager of RMWD, said “They’re very qualified.”

The North River Road Land Outfall conveys wastewater to Oceanside’s San Luis Rey Water Reclamation Facility. The pipeline is nearly 3 miles in length, from just west of state Route 76 to the intersection of Stallion Drive, and 58 maintenance holes provide access to various parts of the infrastructure. The vitrified clay pipe is 15 inches in diameter, and the sewer relies on gravity for its flow.

The rainfall during weather year 2018-2019 caused wastewater flows at the Stallion and North River Road flow metering stations to exceed capacities. The increased flow is believed to be due to significant infiltration and intrusion of rainwater into the wastewater collection system.

In June 2019, Rainbow staff began an evaluation of the vitrified clay pipe which involved clearing the line and conducting a video and photographic inspection of nearly 1 mile of pipeline and 15 maintenance holes. The video inspection revealed multiple repair needs. Another section was inspected in October 2019.

Rainbow staff began developing the logistics of repair efforts. The plans and specifications would be addressing broken or badly cracked sections of pipe, infiltration and intrusion, raising maintenance holes to finish grade, lining existing maintenance holes and providing cast in place pipe at the worst sections.

The March 2020 rains caused another overflow of the pipeline. Rainbow staff conducted video and photographic inspections and observed two sections which are in imminent danger of collapsing.

Kennedy declared an emergency April 17, so that repair work could commence before the next Rainbow board meeting. The April 28 board vote ratified Kennedy’s action and appropriated additional funding for the repair work. Kennedy issued a contract to SCW, and following preparations, SCW began the repair work, April 19.

Rainbow had planned to repair the North River Road Land Outfall over a multiyear period, but the immediate risk led to the decision to repair the entire 3-mile pipeline as soon as possible. During the emergency Hoch Consulting was retained to assist Rainbow staff in finalizing the plans and specifications.

As the inspections and research were being conducted, Rainbow staff decided that Hoch was best suited to expand and expedite the plans and specifications needed for the repair work to be advertised for bid.

Rainbow staff and Hoch worked together to prepare a phased construction approach which will allow the sections with the worst conditions to be addressed first and remaining phases to follow.

A 5-0 Rainbow board vote, June 23, approved a $151,180 contract with Hoch Consulting for the preparation of the bidding documents and for engineering support to the district.

The first phase will excavate and make repairs to the pipeline, replacing the vitrified clay pipe with polyvinyl chloride pipe.

“We bid that out to our pre-qualified contractors,” Kennedy said.

Kennedy said he expected the current phase to be complete by mid-September.

“We want to get that project in before we get the rains,” he said.

The second phase will line high-priority sections with cast in place pipe. Approximately 9,000 feet of pipe will be included in that rehabilitation.

Rainbow staff advertised that phase for bid July 17 and set an Aug. 11 bid opening date, so a contract is expected to be awarded at Rainbow’s Aug. 25 board meeting. The third phase will rehabilitate maintenance holes; Rainbow staff and Hoch Consulting are working on the preparation of the bid documents.

Joe Naiman can be reached by email at [email protected].