Dennis O'Hara / Lake Superior Magazine illustration
Our Working Water
Beneath Duluth’s new Sister Cities Park along the Lakewalk is an 8.2-million-gallon holding tank to catch untreated sanitary sewer overflow.
Gathering to enjoy one of Duluth’s newest parks, visitors can get a great view of Lake Superior and Canal Park and can take advantage of the benches, viewing scopes, green space and an homage to Duluth’s Sister Cities. One would hardly believe that beneath their feet is an 8.2-million-gallon holding tank helping to make sure untreated sanitary sewer water doesn’t gush into the Big Lake.
After 14 years and $155 million, the city of Duluth and Western Lake Superior Sanitary District, which serves 17 communities, met federal and state decrees to end sanitary sewer overflows at 18 locations that in a decade had dumped some 47 million gallons of untreated sewage water into the Lake during heavy rains.
“It was an embarrassment,” Mayor Don Ness said in announcing the end of the decrees in June 2015. “Today we celebrate our success. We have not had a single overflow in over three years and the regulatory consent decree has been cancelled. It was not easy. We have all paid more in our sewer rates, homeowners had to make expensive repairs to their private lines, utility workers have prioritized their efforts for many years, and we have prioritized sewer infrastructure ahead of other projects.”
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Dennis O'Hara
Our Working Water
The new holding tank in Duluth sits behind public restrooms and is camouflaged with greenscape and wall sculpting.
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Courtesy City of Duluth
Our Working Water
Water treatment means two systems for cities – drinking water and wastewater. This graphic gives a snapshot of Duluth’s drinking water supply system.
Duluth, with its population of 86,211, is far from the only municipality investing heavily in treatment of the waters coming out of and returning into Lake Superior, but its experience does show the costs felt by all. Big or small, all towns must tackle treatment of drinking water into their homes and businesses and then treat the wastewater leaving them.
Ten years ago, Bayfield, Wisconsin (population 487), and Pike’s Bay Sanitary District covering about 20 percent of Bayfield Township sought state and federal grants to build a $6 million “demonstration facility,” handling an average of 100,000 gallons of wastewater each day. About $4 million was added to the price tag to install a force main pipe to the facility and remove a treatment lagoon site.
A $2 million project in Rossport, Ontario (population 65), created a top-notch drinking water treatment facility that went online in 2008 and serves 46 homes and five hospitality businesses. Whether large or small cities, the investments always seem big, but not investing can be costlier.
“When you’re sitting on the largest source of fresh water in the U.S. and Canada, you really have to take care of it,” says Rita Gowen, in charge of Rossport’s drinking water treatment plant.
In this story, you’ll find a few snapshots of various sized water works using the Lake to show the big picture of the challenges of bringing water from Lake Superior to our faucets and back again.
Quenching the Thirst
Courtesy WLSSD
Our Working Water
An aerial view shows the other end of the Duluth system, the wastewater treatment plant of the Western Lake Superior Sanitary District.
When the town of Rossport hired Rita to operate its state-of-the-art drinking water treatment plant, it got a “two-for.” Rita’s husband, Peter, a retired paper mill and railroad engineer, does the “heavy lifting,” she says. Rita, Texas-raised, met Peter, a local, in an online chat room. After more than a year of long-distance courting, she moved north, married Peter and became involved in the community.
Asked why Rossport’s plant is “state-of-the-art,” Rita says matter-of-factly (and tongue-in-cheekly): “It’s new.”
The system, though, is worthy of the credit. After drawing water from a pipe nearly 1,000 feet out and 15 feet deep into Lake Superior (“Cleanest source in the world,” Rita affirms), the system adds chlorine, a basic in all drinking-water processes, to eliminate bacteria, and uses a slow sand-filtration process to remove the solids. It has three potable water reservoirs holding 9,000 gallons each. After traveling through five ultraviolet filtration units and then getting re-chlorinated, the water is ready for consumption. “No fluoride,” points out Rita, an addition never used there.
Usually the system handles 300 to 400 gallons an hour during peak seasons – which are summer and dead of winter – and about 220 gallons in the shoulder seasons. The peaks come in summer because of extra visitors and lawn watering and then again when the temperatures dip below freezing “when people are trickling water in their homes to keep the pipes open,” Rita says.
The drinking water treatment plant is just down the road from the Gowen house and although they go to the plant every day, monitoring equipment via computer allows them to keep an eye on it from a distance, Rita says. “We’re able to call up the plant and make process changes from home.”
Rita got hired to run the water system a couple years before the new plant came online. A five-member Local Services Board sets the fees and oversees Rita.
Courtesy WLSSD
Our Working Water
WLSSD lab staff collect and test samples from sewer users.
Since 2006 when she started, major upgrades include discovering and plugging two major pipe leaks that were filtering through the sand and back to Lake Superior, draining 1,500 gallons an hour and approaching the full capacity of their drinking water treatment plant. Recently the town applied for, and received, a provincial grant to create loops out of two pipeline dead ends “so that the water is flowing constantly through the system,” Rita says. “There’s a new pump under the community hall to help circulate the water in the wintertime, to keep the water from freezing.”
Rita feels good about the investment Rossport has made for its citizens and for its Lake. Perhaps coming from Texas, she knows the value of lots of fresh water. “One of these days, our Lake is going to be the big prize.”
It’s worth noting that not all shore-side towns use Lake Superior for water. In Michigan’s Keweenaw Peninsula, for example, many towns depend on deep wells ranging from 50 to 200 feet deep. Adams Township, south of Houghton, provides water to a number of communities, including Hancock, thanks to three 200-feet deep wells and a 250,000-gallon storage facility. The city of Houghton gets its water from three 50-foot wells. That city uses about 1.1 million gallons a day. With well water, like Lake water, chlorine is the main and sometimes only additive to prepare it for consumption.
The water of Lake Superior, though, is a major resource for our largest cities.
For more than 130 years, the city of Marquette has gotten drinking water from Lake Superior. It operates a filtration plant on Lakeshore Boulevard, producing an average of 3 million gallons of potable water daily but has a daily capacity of more than 7 million gallons. The plant’s laboratory, which daily tests its own water system, also tests the water in all public swimming pools and hot tubs, including those in hotels and schools, and at public beaches.
Courtesy WLSSD
Our Working Water
District workers adjust a treatment plant pump.
Duluth also has a long history of water delivery. The desire to eliminate waterborne illnesses for its residents, and an interest in picking up natural gas as a utility, pushed the city to purchase the Duluth Gas and Water Company in 1898 for a whopping $1.2 million. Today the system covers three nearby towns in addition to Duluth. Interestingly, water is not the major expense when pumping almost 6 billion gallons each year. The city pays the Minnesota DNR about $45,000 a year or so for “borrowing” the water, one might say, since much ends up back in the Lake. Electricity is the most expensive ongoing cost for Duluth’s $3 million-a-year operation, but the city also is replacing its 100-year-old pipes whenever road projects allow. “We have about 430 miles of water main,” says Mark Proulx, Duluth’s water plant supervisor, “and it costs about $1 million a mile to replace.”
While Duluth’s drinking water treatment is similar to Rossport’s, Minnesota requires the addition of fluoride, reported to prevent up to 25 percent of cavities in children. The folks at the Duluth plant advise those with older plumbing to run water several minutes before filling a glass to reduce exposure to things like lead from old pipes. And a water container in the fridge means less waste when you want a cold glass of the good stuff.
Flushing the System
Getting water to your faucet is one direction for the Lake’s working water. Returning it back from your home or business, though, is no easy task.
Susan Darley-Hill gives tours of the Western Lake Superior Sanitary District’s wastewater treatment operation. We asked what questions come up most often.
“People don’t even know what questions to ask,” she says, “because they don’t even think about it.”
“It’s an essential part about living in a community; every community has to deal with its water,” adds Sarah Lerohl, environmental program coordinator for WLSSD, but she agrees that “if everything is going right, they don’t think about it at all.”
Rita Gowen
Our Working Water
The tanks that Peter Gowen stands beside are used for drinking water treatment in Rossport, Ontario.
That’s the way the wastewater treatment operations all around the Lake like it. For workers at those facilities, though, thinking about treatment is a 24/7, 365-days-a-year preoccupation. In fact, in the command room at WLSSD, where video and electronic monitoring covers the vast 530-square-mile district, you’ll find a treadmill tucked in one corner. The room must be attended nearly all the time and being able to get some activity while still watching the monitors is helpful.
Protection of Lake Superior and its watershed from the use we make of its water is a major reason why even small communities invest big money in the best facilities.
The Greater Bayfield Wastewater Treatment Plant covers the city of Bayfield and 20 percent of the township. The 10-year-old, $6-million facility is a point of pride for the communities and for Joel Weber, the local man who found his niche in water treatment.
Joel, born and raised in Bayfield, joined the military at age 18 and then enrolled using the GI Bill at Vermilion Community College in Ely, Minnesota. Like so many local youth, he wanted a career in forestry – or something that would get him out into the woods. His advisers pointed out how few jobs were available in that profession at the time. They suggested water resources. “There are a lot of jobs and a hiring rate in the 90th percentile,” Joel was told. The added incentive – even very small towns need to handle wastewater, and this career could be a path back home. Starting south of Rochester, Minnesota, and moving into Wisconsin and finally back to Bayfield, that path worked.
When he arrived in 2001, the Bayfield city wastewater treatment plant, situated on prime land beside the marina, was undersized, landlocked and at the end of its lifespan.
“It was 15 years ago when we started putting pen to paper,” Joel says. The time was right to tap grants from the Clean Water Fund of the Wisconsin DNR, plus grants from the U.S. Army Corps of Engineers and the Great Lakes Protection Fund. Thus 10 years ago, Bayfield and surrounding rural communities were able to build a state-of-the-art facility set on 11 acres of outside town, as well as pipe upgrades to the tune of $10 million. In fact, the plant is considered a demonstration model for zero discharge into Lake Superior.
The basics of this wastewater system echo those found everywhere. The process is not chemical, it’s biological. “Pretty much all treatment plants are biological treatment, even a simple lagoon system,” Joel says. It all depends on the same kinds of little critters, mostly bacteria, that munch on waste everywhere. Called “mixed liquor” in the biz, Joel describes it as “basically the nuts and bolts of the treatment process.”
Our Working Water
It seems so simple on paper, but keeping the proper mix and flow is critical in handling waste water, which means constant monitoring for WLSSD, which serves 17 communities and four major industries along the St. Louis River.
Luckily, most of the to-be-removed stuff in wastewater is biologically digestible or can be easily filtered out before it reaches the bacteria. The process (shown in the graphic) starts with what arrives in the sanitary sewer pipes – those directly connected to homes and businesses, and not to be confused with the storm sewer system that directs rain water and melted snow directly into lakes and rivers. (This is why we do not pour chemicals or old car oil down the storm drain.)
To stay happy, the tiny waste-eating critters need to be fed (no problem there; it comes with the water) and to get adequate oxygen for the task required. The Greater Bayfield plant, with its expansive space, uses a mechanical turbine to create the oxygen. At WLSSD, where the plant has a small footprint relative to its large capacity, workers supercharge the bacteria ponds with pure oxygen. Using a natural process to handle the 40-million-gallons-a-day, 10-hour turnaround that WLSSD averages, would require 18 miles of the St. Louis River, Susan explains.
There are problems, of course, that can arise even with this simple system. Some garbage tossed into the system cannot be caught by filter screens and must be manually removed. Those “flushable” wipes can be flushed, but must be culled manually in the final process. Toilet paper is fine to flush; facial tissue, cotton swabs, prescription medicines, tampons and rubber duckies are not. Also, plastic microbeads – the kind often found in exfoliating soaps and scrubs – may not be caught by the system and end up in the Lake; their use was recently banned in a bipartisan-passed law just signed by President Obama.
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Pike's Bay Sanitary District
Our Working Water
Joel Weber returned to his hometown of Bayfield, Wisconsin, to operate the $6 million Greater Bayfield plant situated on 11 acres of land outside of the city, handling 20 percent of Bayfield Township.
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Pike's Bay Sanitary District
Our Working Water
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Pike's Bay Sanitary District
Our Working Water
A major problem for any wastewater treatment operation is if those invisible little workers get wiped out. Back in 2008, that’s exactly what happened at the Greater Bayfield plant when roots and such in the pipes were chemically scoured. Under a misunderstanding that the system handled 1 million gallons of water a day, the contractor applied the root-control agent accordingly. The system actually averages 120,000 gallons daily, with a summer peak of 180,000 and a winter low of 60,000. This was not a peak time.
“It was like watching a train wreck,” Joel describes the removal product arriving through the pipes. “My bioactivity just started dying. Thank God the product didn’t linger.” (The control agent, by the way, breaks down quickly and safely, but still killed the working bacteria.) Joel had to bring in a few thousand gallons of “mixed liquor” from the Ashland plant and repopulated his wastewater treatment tanks.
While bacteria shoulder the bulk of the cleaning process, there are lots of extras that can help: ultraviolet lighting, added chlorine and fine-particle filtration systems among them.
The largest expense for any treatment plant – taking water out or sending it back – is never water; it’s electricity. To reduce costs, the Greater Bayfield plant uses computer controls and sensors when firing up the oxygen generator and other processes needing electricity. “You’re trying to hit the right mark,” Joel says. Similar energy-saving measures are in place at all the other plants.
Cleaning wastewater to return to the St. Louis River (and ultimately Lake Superior) is the workaday job for WLSSD, but the facility has harnessed some end products to make the system earn a little payback. The leftover sludge from the cleaning process is put into digesters and broken down by a another set of bacteria at high temperatures, killing any pathogens. In doing their work, the bacteria produce a methane-rich biogas that can be harnessed to generate electricity and help to run the process. In the end, the sludge becomes biosolids, a fertilizer rich in nutrients and organic matter used by farmers and in mine reclamation projects.
Just as with the treatment of wastewater, this process hurries what would be a natural process. “The better we can follow what nature has done,” Susan says, the better the system works. In the wastewater business as in nature, it’s better if nothing goes to waste.
Courtesy WLSSD
Our Working Water
At the WLSSD process control center, monitors cover all 17 communities within the system.
Droplets
The Lake region’s wealth of minerals, good for a healthy economy, can be dangerous for healthy water. In 1999 in Wawa, Ontario, for example, heavy rains contaminated local water supplies to many-times the maximum allowable level of arsenic in the drinking water, forcing residents to buy bottled water or use water brought by tank trucks. Meanwhile, on Minnesota’s North Shore, centuries-old deposits of water in ancient rock can create well water too salty to drink. Later this year, we’ll take a look at water systems on rural properties.
Minnesota’s North Shore is one of five testing points for a new state initiative: “One Watershed, One Plan.” The idea behind the initiative is to encourage a more global, watershed approach to water management, coordinating the three counties – St. Louis, Cook and Lake – into a single plan to be released this year.
A few numbers from Big City Waters: Thunder Bay has about 40,000 service connections; 3,402 fire hydrants and 719 kilometres (447 miles) of water mains. Marquette has about 5,800 service lines and meters, 800 fire hydrants and nearly 90 miles of water mains. Duluth has 28,131 service lines and meters, 2,659 fire hydrants and more than 430 miles of water mains. Superior has about 9,500 service connections, 1,125 fire hydrants and about 144 miles of water mains.
Municipalities in the United States and Canada must annually report on their local water quality. Many post the reports or make them available in city offices.
Don’t rush to flush, advises WLSSD. Find tips to help households protect our waters by properly disposing of items that don’t belong down the drain, plus videos on the wastewater treatment process at wlssd.com.
According to a recent report, Michigan, Minnesota, Wisconsin and Ontario collectively withdrew 996 million gallons daily from Lake Superior in 2014, a 0.8 percent decrease from the 2013 total withdrawal amount of 1,004 mgd. The major water users were thermoelectric power production (603 mgd) and industrial plants (280 mgd).
