Case studies

Each case study names the plant, the measures installed, the figures with their units and periods, and who measured or verified them.

Pomona Water Reclamation Plant, Los Angeles County Sanitation Districts

In a demonstration funded by a competitive U.S. Department of Energy grant, an upgrade of the aeration system reduced the energy used for aeration from 1,300 to 550 kWh per million gallons. New blowers reduced blower energy by 34%; lowering dissolved oxygen with DO/Nmaster and SRTmaster then reduced it by a further 30%. More than 40% of the whole saving (308 kWh per million gallons) was attributed to the control systems (U.S. Department of Energy final report, 2025). The project received the 2025 CASA Excellence in Innovation and Resiliency Award.

City of Chico, California

A 2018 control project built around DO/Nmaster, with the existing blowers and diffusers, reduced aeration energy per pound of oxygen demand by 47.6%: 1,198,692 kWh a year, verified under PG&E's California Wastewater Process Optimization Program. SRTmaster has been in service at Chico since 2014. The project received the 2020 Water & Wastes Digest Top Project of the Year award for Automatic Ammonia Control.

Metro Water Recovery, Denver, Colorado

Ekster & Associates has been under contract to Metro Water Recovery, a utility treating more than 200 million gallons a day, for DO/Nmaster since September 2026. Commissioning is planned to begin at the end of 2026. The case study will be published when results have been measured.

Published record

The published papers, and the FAQs and white papers for each controller, are listed on the Publications page.

Operators can override Ekster & Associates' control systems at any time, and faulty instrument readings are not acted on.