LOS ANGELES (AP) – Los Angeles Mayor Eric Garcetti has signed off on an agreement to clean polluted storm runoff water and redirect it to the city’s groundwater basin.

Garcetti signed off Thursday on the $40 million project.

He says it is expected to clean up to 100 million gallons of water every year that would otherwise end up in Santa Monica Bay.

The water, runoff from Los Angeles International Airport, currently runs to the Pacific Ocean through an open ditch. Plans call for it to be treated at a newly constructed reclamation plant instead.

Garcetti says three-quarters of the project’s $40 million price tag will come from funds raised by a bond measure LA voters approved in 2004.

Officials didn’t give a timetable for the project’s completion.

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