Mountain View Seeks to Triple Recycled Water Use Over Next Decade Amid Statewide Droughts | News
The City of Mountain View plans to rapidly expand its use of recycled water in the coming years, with ambitious plans to build an extensive network of pipes that can deliver water to areas slated for major new development.
Recycled water currently represents only a small fraction of the city’s daily water use, at approximately 460,000 gallons per day, or 4% of Mountain View’s total water use. But with ongoing statewide droughts and constraints on imported water, city officials are turning to treated wastewater as a sustainable alternative.
City staff say the best option is to expand recycled water infrastructure in North Bayshore, part of a plan that would increase demand for recycled water to more than 1.4 million gallons per day. Other options are to go further and expand the system to East Whisman — a long-term plan that would take decades and cost more than $40 million.
The Mountain View City Council is due to weigh the options at its meeting on Tuesday, March 22.
Mountain View sends its wastewater to the Palo Alto Regional Water Quality Control Plant and is entitled to 3 million gallons of treated water per day, under an agreement that was recently extended. until 2060. This treated water then returns through a network of purple pipes. which runs through parts of the North Bayshore, but does not cross US Highway 101 in the rest of the city.
The city only uses a fraction of its allocation, in part because of the quality of the water itself. The high levels of salinity in the treated water mean that it cannot be used to irrigate certain landscaping and plants – notably redwoods – and can lead to erosion of buildings. A plan to upgrade the Palo Alto treatment facility is underway, allowing the facility to produce “highly treated” water that has many more uses.
Under “Alternative 1,” which city officials are recommending to council, Mountain View would extend pipelines through North Bayshore along streets such as Shoreline Boulevard, Amphitheater Parkway, Shorebird Way and Space Park Way. The plan would increase the range of reclaimed water to include more commercial customers in the area, including Google, and prepare for future water demand caused by major residential and commercial growth expected for the area.
The other alternatives look at different ways the city can take on the costly and difficult task of getting water south of the 101 freeway, particularly in East Whisman — another area slated for major development. The pipelines could cross NASA’s Ames property or run south on Shoreline Boulevard and east along Middlefield Road or Central Expressway. Costs for each of the three options range from $41.4 million to $52.2 million.
The city also faces tough challenges related to improvements to the regional water quality monitoring facility in Palo Alto. Cost estimates have skyrocketed from $22.3 million to $51.4 million since 2019, and city officials fear the Santa Clara Valley Water District is looking to pay for the upgrades using the money earmarked for other water improvements in North County.
Mountain View residents, like those in other North County towns, pay taxes into the State Water Project which helps fund a massive system of reservoirs, aqueducts and pumping stations that circulate water throughout the state. But only about 10% of Mountain View’s water use comes from this system, leaving most residents with the full cost but none of the benefits. In 2017, Valley Water’s board of directors agreed to return the funds — approximately $8.5 million between 2018 and 2024 — through a grant program.
Last August, Valley Water voted to allow these funds to be redirected to pay for upgrades to the reclaimed water facilities, and that $6 million of the $8.5 million should be allocated to these upgrades. Mountain View officials are protesting the decision, saying it was never intended to pay for the improvements using its own separate grant program that could be used for the mountain’s water conservation and recycling efforts. town.
The reclaimed water system expansion in North Bayshore is expected to cost $27.4 million and take nine years to complete, and the city has already laid the groundwork for businesses to take advantage of the purple pipes. Mountain View has passed an ordinance requiring all new commercial buildings over 25,000 square feet to have double plumbing to allow the use of recycled water when it becomes available, especially for uses such as flush toilets. of water.