They may offer just the basics for that most basic bodily function: a bowl, a seat, a tank, a handle and the inner workings designed for no-fuss, no-muss dispatch. Newer, luxury models, on the other hand, utterly redefine “going in style” with their integrated air-deodorizer options, the heated seats, foot warmers, built-in night lights, two-user memory, and music. The quiet-closing lids of top toilets will even rise in welcome as the user approaches the throne.
When business has been taken care of, it’s flush (whether by human hand or by the action of an intelligent toilet) and forget. It goes down the toilet. It goes away. Out of sight and out of mind. But not to people like Bob Donaldson, who spent a career in an industry with the sanitized name of “wastewater treatment.” Thirty years ago, says the Walnut Creek native, it made his De La Salle High School reunions “interesting” when he told former classmates about his role in the process of moving waste from sewers to a destination people may also not like to think about: San Francisco Bay.
“It’s not a very glamorous subject,” he says. “… People have a tendency to avoid anything their body defecates, whether it’s sweat or odor or mucous or ear wax. And, if you think about it, the things that our bodies naturally release have been the source of multibillion-dollar industries. And we are no exception to that. We fall under the category of the ‘eewww’ category.”
Unsuitable conversation in a polite magazine? Not at all. For communities across the nation with aging sewage treatment plants, public sanitation looms the capital improvement elephant in the room. Southern San Mateo County is among them, confronting significantly higher sewer rates to pay for the first major wastewater conveyance and treatment upgrades in nearly 50 years. The first time around, the federal Clean Water Act of 1972 picked up the tab. “Now here we are,” says Donaldson, “the treatment plants that we built in the 70s, early 80s, have worn out. The federal government says, ‘We paid for the first one. The second one’s on you.’”
Finding ways to dispose of waste is as old as civilization, with evidence of the first lavatory-like plumbing systems as far back as 3200 BC in Scotland’s Orkney Islands. The Babylonians molded clay pipe for drainage. The Romans are often credited as sanitation pioneers for the citywide infrastructure they’d installed by 100 AD, including communal public latrines.
Redwood City got its start as a logging port, and, as the town grew, outhouses soon were no longer up to the job. A city ordinance passed in 1893 established rules for constructing, maintaining and connecting to sewers and provided for the appointment of a sanitary inspector. A $23,718 contract was awarded that year to build the initial system. Early sewer pipes were made out of hollowed out redwood logs.
Life on the Peninsula today would quickly grind to a halt without the underground grid that carries waste from homes and businesses, sewage tributaries that course under city streets and connect with larger pipelines and finally to pump stations east of U.S. 101. They, in turn, propel the effluent miles onward, some of it under Bair Island and under San Carlos Airport, and all of it under Redwood Shores and on to the Silicon Valley Clean Water treatment plant where “out of sight, out of mind” does not apply.
On an average day, about 13.5 million gallons of wastewater flow into the plant located on Radio Road, next to the bay. In prolonged, heavy rain, flows can push up against the plant’s current capacity of about 72 million gallons. (Storm water may infiltrate through old sewer pipes or in ones that have cracked or separated, adding runoff to the wastewater.) Improvements that are coming through SVCW’s $495 million Regional Environmental Sewer Conveyance Upgrade program will increase capacity to about 100 million gallons, according to Director of Operations Bob Huffstutler. The RESCU program is being undertaken due to the cost of reliably maintaining an aging system in an increasingly stringent regulatory environment.
The treatment plant offers a peculiar window into the daily lives of its 220,000 customers, in cities from Belmont to Menlo Park and beyond. On weekdays, says Huffstutler, flows start to increase about 7:30 or 8 a.m., after people get up, take showers and use the toilet. “And they stay pretty high until about 3 or 4 in the afternoon,” he says. “People go home. Flows drop off a little bit, and in the evening, they start picking up again. People start cooking, going to the bathroom, those kinds of things. It’s called diurnal flow pattern.” There’s a five-hour window during the wee hours of the morning when repairs can be done. On weekends, it’s the same pattern but an hour or two later. During the holidays, flows drop off about 20 percent from normal.
At the plant, the sewage goes through a complex physical and biological process that starts with primary sedimentation tanks, where settling and skimming removes solids, floating grease and scum. Bacteria is used in the multi-step process whose goal is to remove more than 97 percent of all solids and organic material and 100 percent of pathogens from the wastewater. For a complete description of how it works, go to wwww.svcw.org/facilities/wastewater treatment
Altogether, from that first morning flush, through the treatment process, it’s about an eight- to 10-hour trip from the toilet or the bathroom sink to 50 feet deep in the bay, via an outfall pipeline. Although plants with a deepwater discharge normally are required to do only secondary-level treatment, SVCW must treat to the same tertiary-level as plants further south in the Bay where water is shallower and less dilution happens.
By the time the laundered wastewater gets to the bay, it may not be deemed drinkable, but fish get along in it swimmingly. That’s actually one of the ways (by regulation) that SVCW checks its own process. For the last two years, 95 to 100 percent of the 15-to-30-day-old rainbow trout fry dumped into a laboratory fish tank for regular testing have survived, according to Laboratory Director Bob Wandro. But they have to be destroyed afterward (also by regulation).
“They’re indicative of what life is out in the bay,” says SVCW’s Manager Teresa Herrera, an avid animal rights person who is dismayed that “they survive the test and we have to kill them. It’s a regulation. I honestly don’t know why.”
The wastewater treatment industry is indeed highly regulated, at ever-increasing cost, but it’s also thanks to regulation that facilities are safer places to work and the bay was cleaned up. San Mateo County Public Works Director Jim Porter grew up near the Marina Court area of San Mateo when the sewer plants and garbage dumps were all along the bay.
“(The mud) was black underneath from all the oil and crap that was in the bay mud,” he recalls. “I don’t know what it’s like now but it was awful then.” He guesses that sewer rates have doubled in the 12 years since he’s been in his position. “But the quality of the water in the bay is improving and that’s a direct result of these requirements that these regulatory agencies are placing on people. So although nobody likes to pay higher sewer bills, if you look at the impacts on the environment of all of these regulations over time, as a Bay Area resident, I think it’s a pretty good idea.”
Each city in the joint powers authority sets its own sewer rates, but they’ve been going up, in large part, to pay for the SVCW upgrades. The basic rate in Redwood City has gone from $35.66 a month in 2007-08 to $78.24 this fiscal year. In San Carlos last year, the annual fee (on the property tax bill) was $1,175, and in the West Bay Sanitary District, in Menlo Park, the base fee was $1,126.
Growing up in Walnut Creek, Donaldson vividly recalls riding in the back seat of his dad’s 1960 Pontiac going to visit his grandmother in San Francisco. “We’re holding our nose because the bay stunk,” he says. “It stunk like a sewer.” Treatment plants across the nation were rudimentary, but the 1969 Porter-Cologne Water Quality Control Act in California expanded enforcement authority through nine Regional Water Quality Control Boards. The federal Clean Water Act required plants to go to higher treatment levels and provided funding. With Bay Area population growth since then, “had these laws not been passed, San Francisco Bay would have been dead long ago, and when I mean dead, I mean filled with waste that consumed all the oxygen. And with no oxygen, no life. It would be just a giant cesspool.”
Donaldson got into wastewater treatment in 1979 in the East Bay but came to work in 1985, first as a supervisor, at the South Bayside System Authority, SVCW’s former name. The joint powers authority includes Belmont, San Carlos, Redwood City and the West Bay Sanitary District in Menlo Park, which also takes in Atherton, Portola Valley, parts of Woodside and East Palo Alto, and some unincorporated areas. Donaldson ultimately advanced to operations manager of the plant, which has been in operation since 1982.
In the early 1980s, the wastewater treatment operator’s job was one of the most hazardous in America, he says. Across the country, treatment plants were popping up overnight but the knowledge about how to operate in confined spaces with the toxic gases that are created from decaying waste sometimes lagged behind. Workers could find themselves trapped in toxic pockets. Gas detectors weren’t being used, says Donaldson, and “somebody would see somebody through a porthole that had passed out, and before we understood what was happening, somebody would rush in to save them and would be overcome by the same gas.”
Donaldson barely made it out alive with his own close call once while down in a tank with a three-inch firehose to clean it. Trying to ensure that the tank was thoroughly disinfected, one of the foremen, thinking he was doing the right thing, turned up the chlorine concentration in the water too high. “So when the water came out, the chlorine instantly atomized and I was instantly stuck,” Donaldson recalls. “I couldn’t see. I couldn’t breathe.” He managed to climb a 40-foot ladder and, once out of the tank, began projectile vomiting.
“I just laid there and slowly started catching my breath and I remember just feeling so happy that I got out of there,” he says. “And then took a shower and finished my shift. … And then it just turned into a good story. You didn’t go home for stuff like that. … There were lots of things that we would never do that they just saw as the regular way of doing things back then. Thank goodness for regulation, safety training and people getting smarter.”
At SVCW, safety messages are all about, as is hand sanitizer. Visitors touring the plant are admonished not to touch their faces or their mouths. Signs on the aeration tanks warn not to drink the water. There’s a life ring (never used) on the side of the tank.
Since becoming general manager a year ago, Herrera has put a lot of energy into safety. Industrial sites, she says, are safer than they used to be, but the treatment plant has a lot of contaminants. “Just imagine what you flush down the toilet is what these guys have to be around day in and day out,” Herrera says. “So it’s extremely dangerous.” People aren’t allowed to work around the aeration tanks without proper personnel around them and protective gear such as harnesses and life ropes, and there are various levels of confined space classification. That said, Herrera is an enthusiastic proponent of careers in wastewater treatment – there are jobs for those with high-school to advanced degrees.
Like a handoff in a relay, before SVCW receives the wastewater flow at the pump stations, cities and San Mateo County are responsible for conveying the slurry via a vast, invisible network of sewer pipes of varying age and condition, to which private property owners connect by lateral pipes. In Redwood City, that’s 200 miles of sewer pipe, about 210 in the West Bay district and more than 105 in San Carlos.
The county also administers 10 sanitary sewer districts from the Burlingame Hills to the Fair Oaks Sewer Maintenance District, some with relatively few (400 or 1,500) connections. Fair Oaks, at 11,000, is the largest, according to the county’s Porter. Years ago areas like Emerald Lake Hills – initially developed with “summer homes” — were on septic tanks, but as these began to fail, sewers were installed, financed through assessment districts. As former county areas incorporated into cities, they took over those districts. That’s how the county is left with the remnants.
Each one operates with its own, separate enterprise funds, which can only be used for operations and maintenance of that particular district. Over the years, Porter says, the county has tried to get adjacent cities to take them over “because we think it’s good government.” Residents lose out on economies of scale. In addition, service calls are dispatched out of Redwood City, which increases response time. Agencies must report spills to the Regional Water Quality Control Board, with substantial fines and enforcement action a potential risk.
“It’s the economic benefits of being part of a larger group,” Porter says. “And that applies to all of our districts. So we’ve got these small districts that are flowing into Redwood City who now have a very large obligation to pay off their share of that plant. So we constantly will work with the cities to try to combine the districts. However, it’s a bit of an uphill challenge because of all the liability issues and the regulatory issues and the cost issues. And that’s why it’s a problem.”
Redwood City hasn’t been subject to fines or enforcement action, and Public Works Director Terence Kyaw says his staff tries to stay on top of things so sanitary sewer overflows – aka “SSOs” – are rare. Each must be reported in detail in the California Integrated Water Quality System – from location (by latitude and longitude) to how many gallons were recovered. Kyaw says Redwood City averages 10 to 15 SSOs per year.
Throughout the year, both city and county crews examine pipes for problems like root intrusions, using closed circuit TV for inspections. Fats, oils and grease (aka FOG) are prime offenders, and outreach is made to restaurants and multi-family dwellings not to pour FOG down the drain. “Those are like a liquid ball,” says Kyaw, “but as soon as you hit that sewer main, this is about 10 or 15 degrees cooler underneath. It kinds of gels up, just like cholesterol in our system.” Sometimes a rotary saw is needed to cut a solid greaseball out of the pipe. “It’s almost like beeswax,” he adds. “It’s incredible.”
The city has six “smart” manholes, which monitor flows and sound an alarm when they’re on the rise. Crews can go out and take a look before the situation becomes an SSO, and Kyaw can read updates on his desktop or phone. Sometimes residents with flooding problems illegally hook up downspouts to the sewer line. If caught, they get a talking to about not super-charging the sewer system.
Redwood City’s sewage flows downhill by gravity, mingling with contributions from other outside the city, through tributary pipelines that feed into a large trunk at Walnut Street and Veterans Boulevard. The effluent then goes through the Maple Street Pump Station, and from there, the river of sewage is pumped north. It converges in Redwood Shores with Belmont and San Carlos’s, headed to the treatment plant. The Redwood Shores area is flat, and there are 31 neighborhood sewer pump stations, each with a wet well, according to Kyaw. The pumps keep sending the sewage on to the next well and finally to the SVCW plant — 24/7, 365 days a year.
SVCW’s RESCU program has already replaced a pipeline that conveys sewage from the Redwood City and West Bay pump stations toward the treatment plant. The fifty-year-old, 48-inch force main had been experiencing about two leaks a year – definitely problematic in a national wildlife refuge. Another $100 million project will replace or upgrade the pump stations. (Belmont and San Carlos each have one as well.)
New facilities in front of the Radio Road plant will allow for better filtration of debris from arriving wastewater. A receiving lift station will bring it from a new gravity pipeline that will be built in a tunnel from the Holly Street/Skyway Road area underneath Redwood Shores Parkway to the plant. Last month, a massive tunnel-boring machine arrived from Germany and will be at work for two years boring out a 16-foot-wide excavation about 20 to 60 feet below ground level. The TBM will install precast concrete segments for the gravity pipeline as the machine advances.
Previously, SVCW had been considering conventional open-cut work, which would have both disrupted life at Redwood Shores but also entailed costly work-window and other limitations.
Mike Jaeger is a principal/founder of the engineering consulting firm Tanner Pacific Inc., which is overseeing RESCU’s design-builder. What changed everything, he says, was the San Francisco Public Utilities Commission’s Bay Tunnel Hetch Hetchy water system project, which involved tunneling through notoriously difficult bay mud. So-called “young bay mud” is like Jell-O pudding, Jaeger explains, and “you have to go below that to a denser clay, which tends to squeeze. It can grab onto your machine. It’s not easy material to break down into smaller pieces.” But the SFPUC project proved that tunneling through the more dense material could be done over a long distance.
Jaeger has utmost confidence in the design of the German-engineered machine, as well as the track record for TBMs: “There’s been probably millions of miles of tunnel built around the world, and we expect a successful completion of our project.” Called “Salus,” the TBM will be passing under Redwood Shores Parkway and “we don’t expect that anybody will notice a thing,” says Herrera.
She maintains that the project will be done as efficiently and as inexpensively as possible. Only the third manager in SVCW’s history, Herrera says not keeping up with preventative maintenance is part of the reason for the large rate increases over a short time. “This period of time for SVCW is an anomaly but everybody throughout the nation is facing this. And the more you stick your head in the sand, the more expensive it’s going to be.” Close to home, a similar project is planned in San Mateo and Foster City.
That said, all the waste that flows through the plant is definitely not going to waste. Energy is a high-cost item, but the treatment process itself generates gas (primarily methane). Not only does SVCW cover about 75 percent of its own electrical use, at a net savings of about $1.2 million a year, the agency plans a joint venture with South Bay Waste Management to feed organic, black bin garbage into SVCW digesters. Potentially, SVCW could produce “well over 100 percent” of its own energy needs from the recycled waste, Herrera says. “We’ll have excess gas.”
For years, Redwood City has been using recycled water that has received additional filtration for irrigation of city-owned land but expanded the service in 2007 to make it available to businesses and residents for non-potable uses. The city distributed 232 million gallons in 2018.
From the treatment process, SVCW also recovers biosolids that has uses such as for landfill cover and composting. A small portion goes on for further drying at a small enterprise called Bioforcetech Corp. It was started about six years ago by some young Italians who had just finished university training and came to SVCW with their idea for how to dry biosolids an extremely low energy use. They received the first permit in the United States to transform biosolids into energy and a product called biochar, which they are also selling.
No one has been around the Redwood Shores plant longer than consultant Joe Covello, 77, who arrived in 1978 when excavation had just started and the project was in trouble. Engineers worked night and day on a redesign, he says, but got the plant built and running. It came in at over $50 million. Covello still calls the place “SBSA.”
“I was here on the ground floor. They built the San Carlos pump station while I was here,” he says. “It didn’t exist.” For a construction person, Covello adds, there’s nothing more rewarding than being a part of building something important and working with others to solve interesting problems.
“When I started working here, I never thought I was going to spend the next years probably doing 50 to 70 percent, if not more, of my work in wastewater,” he says. “… A lot of people turn their noses up at it because they think it’s invisible. You know, like it just happens.”
Out of sight. Out of mind.
This story was originally published in the August print edition of Climate Magazine.
