OAKLAND, Calif. (AP) – Officials say residents of California’s East Bay area may notice a change in their drinking water.

The Bay Area News Group reports (http://bit.ly/2eDk6My ) that the East Bay Municipal Utility District customers west of the Oakland/Berkeley hills from Crockett to San Leandro will be receiving water from East Bay reservoirs instead of directly from the Sierra foothills.

District spokeswoman Andrea Pook says people might notice a change in their water but it will be safe to drink. The temporary change begins Friday and will affect about 800,000 residents.

The six-month change in water supply will allow the district to modernize its largest water treatment plant in Orinda. The plant is closing for the $22 million project, which will make it more durable, efficient and resistant to earthquakes.