La Sierra Pipeline Project

La Sierra 201609 0053a
La Sierra Pipeline Project Fact Sheet 
La Sierra Pipeline - FAQ

About the Project

Western Municipal Water District is undertaking an ambitious capital improvement project to provide safe and reliable water for all its customers. The La Sierra Pipeline Project is a nearly $36 million project to provide locally sourced, drought-proof drinking water to our region.

The project will begin on June 26, 2017 and will take approximately 18-months to complete.

To sign up for email updates on the La Sierra Pipeline project, click here.

La Sierra Pipeline Public Meeting

Public Meeting Presentation (PowerPoint presented on Mar. 23, 2017)

Check back here for future public meetings.
Contact Info: Lynne Butler, 951.571.7261 or

How It Will Work

An expansion of the Chino Desalter will increase new water production by 3,500 acre-feet per year. Production capacity at the Arlington Desalter will also be expanded thanks to a new 5,400 horse power pump station.

Then, five miles of 30-inch pipe will be placed underground along La Sierra Avenue to connect the two desalter facilities to the La Sierra Tank. This connection will facilitate the delivery of the new water supply to more than 80,000 customers in Western’s Riverside retail service area.

Traffic Impacts

There will be some traffic interruptions on La Sierra Avenue during the construction period, and all motorists should use an alternate route if possible.

If that isn’t feasible, motorists should obey all traffic control measures in the construction zone between El Sobrante Road to just north of Arizona Avenue.

Work planned in front of Arizona Middle School is scheduled to take place in the summer when school is out of session.

Upcoming Construction and Lane Closures

Thank you for your patience during the ongoing installation of the La Sierra Pipeline.

Tentative construction dates: Jan. 8 to Feb. 16. from 7 a.m. to 4 p.m.
(See map for general affected areas) La Sierra will have one north-bound lane open and one south-bound lane open. 

Affected areas
  • Northbound - La Sierra Avenue at Lake Crest, Lake Knoll
  • Southbound - Lake Knoll Pkwy and Lake Crest Drive 

Construction Hours

Western is limiting construction hours to avoid noise during early morning and late-night hours. Generally speaking, construction will take place between 7 a.m. and 4 p.m., with some exceptions. Detail construction hours are:

Area Near Arizona Middle School (north of Dufferin Avenue):
7 a.m. to 3 p.m.

Area South of the School Zone (south of Dufferin Avenue):
7 a.m. to 3 p.m. if northbound lanes are not impacted; 8:30 a.m. to 4 p.m. if northbound lanes are restricted to one lane

Indiana Ave:
7 a.m. to 3 p.m. on Saturday and Sundays only

Sterling Ave:
7 a.m. to 5 p.m. on weekdays. There may be some weekend work in this area.

La Sierra Pipeline in the News

Efforts to increase local water supply should be embraced 

Project Funding

The La Sierra Pipeline project is not expected to increase the rates charged to customers. The Project will provide high quality source of water that is locally developed rather than imported from Northern California, thereby increasing the District’s water supply reliably to our customers. The project is funded by a Federal Bureau of Reclamation Grant and by Western’s Water Reliability Fund, which is earmarked in Western’s existing rate schedule. Financing is provided by the State of CA’s Revolving Fund Loan program.
Lynne Butler
More Information

Lynne Butler, Community Affairs Representative II