City of Chino to build $20 million water treatment facility

The pipeline, owned by the Metropolitan Water District, will undergo renovation in the next eight to nine years, requiring shutdown for three to six months a year over two to three years.

Chino currently purchases about 35 percent of its annual water supply, Ms. Coker said. 

With continued periods of drought anticipated in the future, water treatment is more sustainable and less expensive than imported water, she said. 

The Chino City Council last month approved a $1.7 million contract with the firm Hazen & Sawyer for engineering and design services for a future State Street Treatment Plant to be built on Benson Avenue, north of Mission Boulevard, in the city of Ontario. 

Ms. Coker said the goal at buildout is to supply 50 percent of demand with city produced groundwater.

“The city is adding and expanding existing water treatment plants to meet state and federal drinking water standards to maximize use of local groundwater,” she said.

Restoring wells

Ms. Coker said the city’s five-year plan includes restoring existing wells, with no additional wells planned.

Well 14, located near the future State Street Treatment plant, has been out of service since 2008.

It will be treated at the new facility for nitrates and perchlorate above the maximum contaminant level.

Well 12, out of service since 2018, will be treated there for the chemical 1,2,3- TCP above the maximum contaminant level.

The U.S. Environmental Protection Agency has set the maximum TCP level at five parts per trillion.

Water treatment consists of two types of processes: granular activated carbon (GAC) to remove 1,2,3-TCP and ion exchange to remove nitrates and perchlorate.

The treatment plant will use cartridge filters, granulated activated carbon vessels, ion exchange and chlorination equipment for a total treatment capacity of 4,000 gallons per minute.

Ms. Coker said the design process will take about a year, and construction is expected to last at least a year and a half after contractor bids are approved.

Existing facilities 

GAC treatment was completed in 2017 at the city’s Eastside water treatment facility and in 2018 at its Benson treatment facility.

These facilities treat Wells 5, 9, 10, 13, 16, 18 and 19. 

Ms. Coker said the highest TCP concentration was in Well 19 with a concentration of 102 parts per trillion.

She provided the following information on the city’s other wells: 

Wells 11 and 12 were taken out of service because they exceeded the maximum TCP contaminant level. 

Wells 4, 6, and 14 were already out of service due to other water quality issues.

Well 3 is inoperable and not equipped with a pump.

A nitrate treatment for Well 16 became obsolete and cannot be repaired.

Ms. Coker said the Eastside GAC will be expanded to double capacity treating Wells 11, 16 and other city wells, and GAC treatment at the Benson facility will also be expanded.