Dexter Wilson Engineering to design Rainbow's Rice Canyon Transmission Line

Dexter Wilson Engineering, Inc., will be providing design services for a transmission pipeline from the Rainbow Municipal Water District's Rice Canyon Water Tank.

A 3-0 Rainbow board vote April 28, with Michael Mack and Helene Brazier not able to participate in the meeting, authorized Rainbow general manager Tom Kennedy to execute a design services contract with the Carlsbad company for up to $190,880 and found that the design itself is categorically exempt from California Environmental Quality Act review although environmental review will be required for the construction.

Rainbow's Rice Canyon Water Tank obtains potable water from Connection 10 on the Metropolitan Water District of Southern California's First Aqueduct, which conveys treated water through Pipelines 1 and 2.

A transmission line from the Rice Canyon Water Tank will provide multiple benefits. The tank and Connection 10 are currently underutilized, which causes buildup in the tank and creates water quality issues, so the transmission line will allow water in the tank to circulate quicker and improve water quality.

A transmission line utilizing Connection 10 would increase the likelihood of service during an aqueduct shutdown. The tank is less than a mile away from the Horse Creek Ridge development so a transmission pipeline could serve Horse Creek Ridge along with the Meadowood, Campus Park, Campus Park West and Palomar College developments as well as additional projects which have been proposed but not yet approved.

The pipeline could also provide service to the southern Morro zone. "There's no pipeline coming down from there into the main Bonsall area," Kennedy said.

The design services phase of the project will prepare plans, specifications, and estimates suitable for issuing an advertisement for bids to construct the pipeline. The original alignment plans utilized existing Rainbow easements to bring the pipeline to the boundary of Horse Creek Ridge. Rainbow staff issued a request for proposals for the design services in August 2019 and six bids were received by the Oct. 8 deadline.

"We had gotten design prices for this project that were very, very high," Kennedy said.

Rainbow staff reviewed the six proposals and determined that Harris & Associates was the most qualified firm for the design project. A recommendation to award the design work to Harris & Associates for $244,677 was presented to Rainbow's Engineering and Operations Committee, which recommended that the full board authorize the contract.

Pardee Homes is the developer of Meadowood, which is east and south of Horse Creek Ridge. Pardee will be financially responsible for constructing infrastructure within the Meadowood boundaries. The Rice Canyon Transmission Line was initially envisioned to end at the Meadowood development, but Pardee approached Rainbow staff to propose coordination with the design activities.

Pardee is using Dexter Wilson for the design of the transmission line extension through Meadowood. Although Dexter Wilson did not bid on the Rice Canyon Transmission Line design, Rainbow staff asked Dexter Wilson for a proposal.

Due to economies of scale the cost for Dexter Wilson to design Rainbow's portion of the Rice Canyon Transmission Line was $190,880. Rainbow staff considers Dexter Wilson highly qualified to perform the work.

"It made sense to save some money for the ratepayers," Kennedy said.

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