Herriman wastewater upgrade reaches 60% design milestone as state financing lines up

At the Aug. 19 meeting of the Orange County Sewer District No. 1 advisory committee, project engineers and county staff said design work on the Herriman Wastewater Treatment Plant upgrade is on schedule for a 60% design submission in September and that several state financing options have advanced.

The update matters because the full project is large — the presentation used a working project maximum of $185 million — and new low-cost financing and grants could substantially lower the debt burden for district ratepayers.

Mary Beth Miller, who joined the committee virtually, said the project team remains on target for 60% design and that the sludge-handling approach has moved into conceptual design for a sludge-hopper option. "So we remain on target for 60% design, due at the September," Miller said. She described equipment reviews (mechanical and manual screens, wire-wedge screens for scum discharge) and said geotechnical work focused on the new sequencing-batch-reactor tanks has been moved from August into September.

Miller reported progress on access and permitting: the project team received no preliminary comments from the state Department of Transportation on a proposed secondary access off Route 17 and is advancing final design and an application to purchase surplus DOT property for a truck entrance that would reduce construction and operational truck traffic on local roads. She also said the team completed required lead and asbestos surveys for structures that will be demolished during construction.

On regulatory reviews,…