In the past, the County of Maui has had difficulty in finding users for the reclaimed water, primarily because of the high cost of conveying the effluent to individual users. With the assistance of Fukunaga & Associates, Inc. (FAINC) and the cooperative efforts of surrounding landowners, potential users and the County, a functional system was constructed that meets the needs of the users, best utilizes existing facilities at the Kihei WWRF, and provides sufficient storage and transmission capabilities.
The bids received on the project were very favorable, and with minimal change orders required during construction, a surplus of funds was available at the Core Project’s completion. A second project, the Kihei Effluent Reuse Distribution System, Phase I, was added and provided a major distribution arm for the system, serving the area north of the Kihei WWRF.
The construction cost for the Kihei Effluent Distribution System, Phase I, was $682,000. Total construction time was 8 months, with substantial construction completed in December 1998. The contractor for the project was Goodfellow Brothers, Inc.
The subconsultants, MK Engineers, Ltd. and Shigemura, Lau, Sakanashi and Higuchi, Inc. (SLSH), provided electrical and structural engineering services, respectively. MK Engineers, Inc. worked with the County staff and vendors of Supervisory Control And Data Acquisition (SCADA), radio and solar power systems, to develop a solar powered reservoir level control system linked by a radio telemetry system to the County’s SCADA system and effluent pumping station at the Kihei WWRF. The SCADA system is programmed to start and stop the effluent pumps and to control valves that permit irrigation of the Elleair Golf Course and the Monsanto Corporation’s seed corn operations. SLSH worked with the County to optimize the storage reservoir design, utilizing an aluminum geodesic dome cover, in lieu of a conventional concrete roof slab, resulting in cost savings for the County.
The Kihei WWRF currently reclaims between 40 and 50 percent of the wastewater it treats, typically between 1.6 and 2.0 million gallons per day. The rest of the treated effluent is discharged through injection wells located on the WWRF site. It is envisioned that the Kihei WWRF will eventually reclaim 100 percent of its flow as public acceptance and demand for the high quality effluent increases in the future.