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Energy + Get AlertsA clean environment means everything to the city of Bayfield, located on a peninsula in Lake Superior at the northern tip of Wisconsin.
About 500 residents call Bayfield home, but tens of thousands of tourists visit in summer and fall to enjoy the lake scenery, tour the Apostle Islands National Lakeshore, visit orchards atop the surrounding hills, and patronize shops and restaurants near the lakefront downtown.
To help maintain its attractiveness to residents and visitors alike, the city in 2012 adopted a comprehensive Sustainability Plan that covers housing; transportation; agricultural, cultural and natural resources; economic development; intergovernmental cooperation with other nearby communities; land use; and utilities and community facilities.
In addition, in 2006, the City Council passed a resolution adopting the Natural Step Framework and joined communities that have designated themselves as eco-municipalities.
Sustainable utilities
Mayor Gordon Ringberg observes, “Sustainability is about doing the right thing, but it also makes sense for where we are and what our livelihoods are based on. We want to protect the lake, the woods, and everything around us for ourselves as residents, for our visitors, and — more important — for future generations. This is a special place, and we want to keep it that way.”
Tom Kovachevich, Public Works director, and Josh Pearson, wastewater treatment plant operator, are integral to the utilities portion of the Sustainability Plan. They’ve worked on energy-saving and other sustainability projects affecting drinking water pumping, treatment and distribution, and wastewater collection and treatment.
The city is by far the smallest of five participants in the Water Utility Energy Challenge, a competition funded by the Great Lakes Protection Fund and managed by the American Water Works Association. The communities are competing to see how well they can change their operations to reduce the air pollution — especially mercury releases — created by electricity production.
Efficient treatment
The Bayfield water and wastewater utilities have taken various steps to drive down energy consumption and improve efficiency in general. The city pumps its water from two wells on the hills just a few blocks inland from Lake Superior. From two reservoirs, the water flows by gravity through the distribution system. The source water is of such high quality that it requires only low-level chlorination to achieve a chlorine residual of 0.08 mg/L.
The water pumping operation has been the focus under the Water Utility Energy Challenge, according to Pearson. Normal daily pumpage is about 60,000 gallons, although it can reach as high as 250,000 gallons during the peak tourist season.
For the contest, brought to leaders’ attention by Sarah Mather, office assistant, Pearson first established a baseline of pump operation patterns. “I installed radio reads at our pump houses to detect when the pumps call for water and turn on,” he says. “We let that run for a while to determine at what times of day the pumps were running.”
The resulting data showed that some pumping times were falling in periods of high mercury emissions from coal-fired utility power plants. “It’s our goal under the competition to avoid pumping during those times,” Pearson says. “We decided the best way to do that was to manually start the pumps and fill the reservoirs first thing in the morning, when mercury emissions are lowest.
So we run our pumps at that time until the reservoirs are full and then turn them back to auto so that they will start in case of a fire or other emergency.
“At some points, especially during high-usage periods on weekends when no one is in the office, we still run at the high mercury-emissions times because of water demand. But during the week, we’ve done pretty well at controlling our pump times.”
More efficiencies
Efficiency initiatives extend to the wastewater treatment plant, the first advanced treatment facility in Bayfield County, commissioned in 2006. The pumps that lift wastewater to the hilltop treatment facility are fitted with variable-frequency drives, and so is the VFD that drives the aerator for the two oxidation ditches. Aeration is controlled on a feedback loop to sustain the optimum dissolved oxygen level and avoid excessive power consumption.
Biosolids management includes a unique system in which material from the anaerobic digester at about 1.5 percent solids is pumped into a pair of reed beds in concrete enclosures. Pumping at about 17,000 gpd occurs about four days per month during summer.
Meanwhile, substantial work is being done to reduce inflow and infiltration to the sewers and the loss of potable water to leakage. About 70 percent of the water piping has been replaced in recent years. “We have removed a lot of clay tile pipe and put in PVC,” Pearson says. “We’ve replaced almost all 4-inch water mains with mostly 8-inch lines and larger.” Periodically, the city has hired a contractor to listen for leaks with acoustic equipment; that has helped locate problem areas for repair. Losses have declined from about 25 to 20 percent.
When doing street repairs, the city also replaces the underlying sewers and water mains; drain tile is installed in some cases to divert high groundwater away from the sewer lines and limit I&I. Where possible, crews use directional drilling to install piping, thus avoiding major disruptions that would inconvenience tourists.
Other initiatives
Steadily pursuing sustainable options, Bayfield has worked with Wisconsin Focus on Energy to complete a citywide energy audit and install efficient lighting. LED lamps, purchased from Great Lakes Electrical Equipment with financial assistance from Focus on Energy, have been installed inside and outside the water and wastewater treatment plants, the administration building, and the Public Works shop. Street lamps have been replaced by LEDs, and traffic lightbulbs are to be replaced as well.
The energy audit recommendations include installing VFDs on the two well pumps and working with the local electric utility, Xcel Energy to procure lower interruptible rates for facilities equipped with backup generators. Those include the wastewater treatment plant and the larger of the two wells.
For the future, the Sustainability Plan calls for exploration of renewable energy. “We’ve looked at the possibility of putting in solar panels to reduce the amount of electricity we pull off the grid,” says Ringberg, who often rides an electric bicycle between his home on a hill and city hall on the lakefront.
“When we buy equipment, we want it to be at the upper end in terms of being environmentally friendly. We do what we can to avoid overtaxing the resources. It takes about 100 years for a drop of water that enters Lake Superior to work its way out. So whatever we put into the lake will be there for a while. It affects the lake trout, the fishing, and the health of everything in the lake. We keep sustainability in mind and do as much as we can, knowing there is always more we can do to keep working toward our ultimate goals. It’s important for us — we take it very seriously.”