Kerrie Romanow is the former chief sustainability officer and environmental services director for the city of San José. She can be reached at kromanow@me.com.

Cities across the nation are looking for ways to keep their water supplies reliable even during droughts. This is especially true in California, where almost every city will need to conserve more as the state continually experiences drought conditions. For cities or water districts with big, bold infrastructure goals, look no further than San José.

The city has focused on adaptation and water resiliency for over a decade. San José’s wastewater treatment and municipal water system infrastructure are stronger than ever and can serve as a model for other cities.

Water supply innovation boosts sustainability

The Santa Clara-San José Regional Wastewater Facility (RWF) works every hour of every day to clean the region’s wastewater to high standards. The facility uses a treatment process that mimics how nature cleans water. It serves 1.4 million customers — including over 17,000 businesses across eight cities — and has been doing so reliably for decades. But doing so is much harder now than it was decades ago.

To mitigate the impact of blackouts and grid instability, the facility now has its first-ever emergency power system and an updated computer room that lets operators make adjustments instantly. Emergency generators can boot up within 18 seconds to power critical systems. There’s also more space for emergency operations and emergency response teams to gather and plan, further bolstering the facility’s resiliency.

The city also invested in a cogeneration system. Completed in 2020, this high-efficiency system generates electricity from digester gases — which would otherwise cause air pollution — and heat from the combustion process used for the water treatment process. Everything produced at the facility gets reused.

San José has also made strides to reduce its dependence on imported water. Increased water use and climate change-fueled droughts have strained the city’s imported water supply in recent years. The city-run South Bay Water Recycling system is helping offset that demand by delivering recycled, non-potable water to over 1,000 commercial customers a day.

These sorts of investments are practically a must in many communities: The more cities focus on local, non-potable water supply options, the less they need to use water that would otherwise be treated to irrigate public parks, cooling towers, golf courses, campuses, and other community amenities. This reinforces an important piece of the city’s Climate Smart San Jose initiative — to take climate action by saving water.

Fathead minnow creates a bulky first-line defense    

It’s not just people and plants that San José watches out for: It’s fisheries too. The RWF’s laboratory monitors and tests water samples every day to ensure successful water purification and high-quality wastewater discharge. The lab tests over 55,000 species annually and tracks Bay conditions, toxicity levels, chemical parameters, and other potential pollutants.

After many nationwide, independent scientific studies, the California Water Boards selected the fathead minnow, a species of freshwater fish, as the city’s new test species. This minnow is a benchmark for other species. If they can survive in the waterways, other species likely can too. Since April 2020, the city hasn’t failed a chronic toxicity test.

The RWF must not only respond and adapt to rising sea levels but also changing water conditions and increasing population. The continued presence of the fathead minnow gives city officials confidence that the RWF can detect any changes at the facility that could harm the Bay conditions and habitats that draw people to the area.

Technological improvements boost water delivery efficiency

The San José Municipal Water System is also undergoing several changes to ensure its more than 100,000 customers have an even safer and more reliable water supply. Using remote meter readings and automation, staff can simply drive by each water meter to pick up the data. The city can also now better pinpoint water leaks, allowing for further conservation.

The new Remote Computer System mirrors Muni Water’s computer room, communicating with water pump stations throughout its service area. Using automated water tank level readings, the remote system monitors the flow of clean drinking water for about 12% of San José residents.

The mobile command system was put to the test — and succeeded — in February 2024 after intense storms caused massive power outages for several days. This could have caused catastrophic loss of drinking water to over 100,000 customers in San José. Instead, the system’s remote capabilities allowed drinking water to flow during widespread electrical power loss.

All these improvements increase San José’s readiness for whatever climate change throws its way. Through practical experience handling the impact of worsening weather events, improved technology, and innovative approaches to updating decades-old water infrastructure elements, the city is making sure its environmental footprint is ecological and adaptable for the future.