Years in the works, Menlo Park's first recycled water system is up and running, carrying wastewater from local households to the Sharon Heights Golf & Country Club, where a new treatment facility cleans the water for irrigation use, keeping the golf course a lush emerald green.
At a ribbon-cutting ceremony held Tuesday, Oct. 27, officials from the West Bay Sanitary District and its private partner in completing the new wastewater treatment facility, the golf and country club, spoke about what the achievement spells for the future of recycled water in Menlo Park.
Attendees wore purple masks – to match the purple pipes that carry recycled water – and sat 6 feet apart as stakeholders described the efforts that went into the project.
The project, which cost a total of $22.5 million, was funded with a $5.3 million Proposition 1 grant, a voter-authorized state program aimed at funding projects to help meet long-term water needs, and $17.3 million from the golf and country club, said Phil Scott, retired district manager at the West Bay Sanitary District. The club is repaying the construction loan and paying for operations and management costs, and the sanitary district is managing the facility at cost, said current district manager, Sergio Ramirez.
Since the facility started delivering water at the end of July, it has already recycled more than 15 million gallons and has the capacity to process about a half million gallons of water per day, Scott said.
The golf and country club is one of the Menlo Park Municipal Water System's largest users, according to Ramirez. Cutting the club's reliance on municipal water, which comes from the Hetch Hetchy reservoir in the Sierras, reduces demand on the municipal water system by 14% during the summer months, he said.
The system, with the facility nestled behind the golf course toward Interstate 280, actually starts 2 miles away on Sand Hill Road, where it intersects with Oak Avenue. There sits a bright green pump station, where wastewater is collected from the nearby homes and pumped uphill, through pipes under the sidewalks, up to the treatment facility, said Matthew Mirenda, senior project manager for Anderson Pacific, the contractor that constructed the facility.
The district also improved some segments of the walking path along Sand Hill Road in areas where it had to dig it up for the project, Ramirez said.
The wastewater is pumped up, where it goes through a series of fiberglass tanks where the smell is scrubbed using bacteria that break down the substances causing the odors.
From there, the wastewater goes through a membrane bioreactor process, working through multiple tanks containing bacteria and no oxygen, then lots of oxygen, to trigger reactions that break down solids in the wastewater. Once the effluent reaches a certain level of cleanliness, it is passed through a membrane cassette, between one and two microns wide, to get rid of particles, and then treated with UV light to kill any remaining bacteria. Once it is considered sufficiently clean, the water is sent down the hill toward a reservoir in the middle of the golf course where it is used for irrigation purposes.
Quinten Green, chief plant operator, was busy checking the treatment tanks to sample the oxygen and pH at different steps of the process during the tour. He said he was excited about the system as a new way to treat waste and believed that type of system would grow in popularity in the future.
The board at the golf course determined years ago to try to work toward water independence to ensure it could keep its course green for the foreseeable future. As far back as 2008, a club committee determined that operators should view the use of potable water as a short-term solution and work toward finding a cost-effective water supply that would not be vulnerable to drought restrictions, said Andy Duncan of the golf and country club.
Mirenda said that while some elements of the initiative were complex – determining the correct scale for the project and working through the details of a public-private partnership – the overarching goal was simple: The club needed water, and the sanitary district had plenty of water, albeit used household water. He added that he feels the project paves the way for other country clubs and public agencies, creating a model for how to recover water.
In the future, the district plans to build a similar facility in Menlo Park's Bayfront area, in the area rezoned in the city's ConnectMenlo process, but the initiative is still in the early discussion phase, Scott said. The sanitary district is also working to install purple pipes throughout the district in preparation for more recycled water systems throughout the area, Ramirez said.
Already, the system has provided some interesting insights to operators about its human waste contributors. For instance, when the system began collecting water in the spring, the time of day with the greatest level of daily water use – generally when people are going through their morning shower and restroom routines – was around 7:30 a.m. As the pandemic has worn on, that high point now peaks as late as 10 a.m., according to Mirenda.
Another pandemic behavior that the district dealt with was an uptick in the number of "flushable" wipes ending up in the system. While such wipes may disappear down the toilet, they don't break down easily, and were causing clogs. Instead of mailers, Ramirez said, the district used online tools like Facebook and YouTube to discourage users from flushing these wipes. Since then, the problem has seemed to improve.