Greenfield expansion means the city will need a bigger, newer wastewater treatment plant.

The city of Greenfield has grown exponentially in recent years, and several projects are still on the way, including a hotel on Walnut Avenue, an apartment complex on 12th Street, a new community center and a proposed annexation to the southeast of the city, along Highway 101.

More people means more waste, and the city’s wastewater plant needs to accommodate it. Currently, the plant processes 1.5 million gallons per day, but officials say that won’t be enough for upcoming growth.

On Oct. 11, Greenfield City Council approved $4.4 million toward the design of a new wastewater plant. The new plant will be a five-year project and can process 2 million gallons of wastewater per day; its estimated cost is $59 million.

In 2018, the existing plant spilled 3 million gallons next to the Salinas River. Greenfield settled and paid a $172,115 fine to the Central Coast Regional Water Quality Control Board. The spill added urgency to a series of studies on the current facility that were already in the works. Last year, Greenfield adopted plans that included replacing the plant and the installation of a membrane bioreactor treatment system – a newer technology to process wastewater.

The future plant could be expanded to produce recycled water fit for irrigation and industrial use. “We’re going to put more water into the ground or groundwater basin,” Public Works Director Jamie Tugel says.

The city applied to the Clean Water State Revolving Fund for nearly $629,000 in August. Currently, the city is borrowing money from its enterprise funds for the early project stages, and possibly from its American Rescue Act funds.