Lower electricity costs at your treatment plant, with the equipment you already own

Blowers, which supply air to the tanks where bacteria clean the water, are the largest single users of electricity at most wastewater treatment plants. Ekster & Associates' machine-learning based control systems supply only the air the process needs, minute by minute, instead of the large safety margin most plants supply today.

What it has saved

Pomona Water Reclamation Plant, Los Angeles County Sanitation Districts. In a demonstration funded by a competitive U.S. Department of Energy grant, the plant first replaced its old blowers, which reduced blower energy by 34%. Lowering the oxygen level with DO/Nmaster and SRTmaster then saved a further 30%, while nitrogen removal was maintained. Over the whole project, aeration energy fell from 1,300 to 550 kWh per million gallons treated. The project received the 2025 CASA Excellence in Innovation and Resiliency Award (awarded to the Los Angeles County Sanitation Districts and Carollo Engineers).

City of Chico, California. A 2018 control project built around DO/Nmaster, with automated valves, airflow and ammonia meters, and improved blower sequencing, reduced aeration energy per pound of oxygen demand by 47.6%, using the plant's existing blowers. Under a Pacific Gas and Electric (PG&E) energy efficiency program, an independent engineering firm verified savings of 1,198,692 kWh of electricity a year, worth $168,051 a year at 2018 rates. PG&E paid the City an incentive of $121,208.

Who uses it

• Los Angeles County Sanitation Districts, which serve 5.5 million people (Pomona Water Reclamation Plant): DO/Nmaster and SRTmaster; BLANKETmaster under contract since October 2026
• City of Chico, California: SRTmaster since 2014; DO/Nmaster since 2018
• Under contract: Metro Water Recovery, Denver (200+ million gallons per day)

The Chico project received the 2020 Water & Wastes Digest Top Project of the Year award for Automatic Ammonia Control.

What it involves

• No new blowers. The control system works with the plant's existing blowers and its existing plant control system.
• No capital project is required for the control system.
• No equipment sales. Ekster & Associates sells no hardware. Where additional instruments are needed, the plant buys them from any supplier, to recommended performance specifications that Ekster & Associates provides.
• Operators keep authority. Plant operators can override the control system at any time, and faulty instrument readings are not acted on.

Why it is a low-risk decision

• Independently verified. The Chico savings were verified under a PG&E program, and the Pomona results are published in a U.S. Department of Energy final report.
• Proven over time. The control systems have been in service at Chico since 2014.
• Named references. Plant staff at Chico and Pomona are available to speak with other utilities.
• A fixed price. The assessment states the price before any commitment.

The cost of the present safety margin

Most plants hold more oxygen in their tanks than the process needs, as a safety margin. That margin is paid for continuously in electricity.

Next step: a free plant assessment

Send one year of operating data and energy bills. You will receive a written estimate of savings in kWh and dollars, the assumptions behind it, any changes required before installation, and a fixed price. If your plant is already operating efficiently, the estimate will say so.