SJW workers installing a new residential waterline

Investing in Our Water System Today

Building for the Next Century

Making sure that our customers have safe, clean and reliable water service means that our water system must be maintained and upgraded as time goes by. In our approximately 140 square mile service area, there are 2,400 miles of water mains, 106 tank and reservoirs, 20,143 hydrants, and 35,143 valves - that’s a lot of infrastructure to maintain!

In 2020, SJW continues its commitment to maintaining and upgrading our water system, investing almost $120 million to ensure we can safely and efficiently serve customers now and for the next 100 years.

Here’s an overview of our key projects.


Water Mains

Most people never stop to think about water mains because they’re located underground. For us, it’s at the top of our to-do list. Making sure that the pipes that carry water to your home or business are replaced before they reach the end of their useful life and cause a large water leak is our priority.

Our biggest yearly infrastructure expenditure continues to be main replacements. Our industry-leading 1% replacement rule means that we will replace 24 miles of our total 2,400 miles system throughout our service area in San Jose, Campbell, Cupertino, Los Gatos, Monte Sereno, and Saratoga at a cost of almost $50 million. The newly installed pipes are made of cement-lined ductile iron and should provide safe and reliable service for the next 100 years.

Reservoirs and Tanks

More than $30 million is dedicated to upgrading and replacing our reservoirs and tanks. This makes certain water is available to our customers and firefighters 24/7, every day of the year.

A large reservoir replacement project at our Columbine Station in San Jose is scheduled to begin construction in January 2020 and be completed in 2023. Built in 1963, the existing 20-million gallon earthen embankment reservoir will be replaced with two identical 5-million gallon concrete tanks.


Artist’s rendering of the new tanks planned for 2020 at Columbine Station


Original construction photo of the Columbine Station tanks from 1963

Acoustic Leak Detection



Finding leaks before they reach the surface is a sure-fire way to save water. One of San Jose Water’s goals is to minimize water loss in our distribution system to lower costs and protect the environment. Investing in a world-class Acoustic Leak Detection is a key component. This program utilizes sensors placed on fire hydrant caps to monitor sounds within our water system to identify leaks.



  • Purchasing or treating greater amounts of water than customers utilize
  • Expending additional energy and corresponding greenhouse gas emissions to supply water not used by customers
  • Experiencing fewer water main breaks which cause considerable damage and disruption

Thus far, 88 leaks have been identified, saving millions of gallons of water while also minimizing damage to property and inconvenience to customers. San Jose Water is very proud of our annual water loss rate of approximately 7%, which is far below the national average of 16%.