Closing the tap
Lush green lawns and waving sprinklers are a common summertime sight in Woodbury. But as state and city officials become more sensitive about water security, the city is taking a look at ways homeowners can conserve water during the warmer months.
The city recently partnered with the University of Minnesota’s Minnesota Technical Assistance Program (MnTAP) to launch a pilot program that put 50 free Rachio IRO 8-zone smart controllers into the homes of residents with the goal of measuring their effectiveness for conserving water.
Unlike clock-based timers that arbitrarily turn on and off sprinklers, smart controllers are able to gather information like weather updates to tell sprinkler systems to shut off when it rains or if it rained before scheduled watering times. The wifi-enabled controllers also calculate how much water to use based on sunlight exposure, soil moisture and sunlight exposure. A mobile app can also control the setup.
The city paid $7,500 for the controllers and $4,000 to MnTAP for its services, which includes a full-time intern from the university to work with the city.
In exchange for the university's resources, the city also provides valuable experience for a student-intern who works with the city and makes recommendations during the course of three months. And the city takes those recommendations seriously.
While working last year on a partnership project between MnTAP and the city on ways to conserve water for Woodbury businesses, geology student and MnTAP intern Ben Heinle recommended the city should explore smart controllers as an option for residents.
“I think that there’s more benefits going to residents’ homes than businesses,” Heinle said, adding that many of the businesses he observed already had modern irrigation systems in place to cut down on their water bills.
But for average homeowners, Heinle suspected many don’t know about smart controllers and the added value they may provide.
“I don’t think people think about their irrigation system much,” he said.
Now a graduate student at the University of Wisconsin-Madison, Heinle said he hopes to continue working on solving some of the more pressing region-wide water issues.
State officials have raised concerns about water security and water levels in underground aquifers following years of plummeting water levels at White Bear Lake. In light of their concerns, Woodbury set forth an ambitious plan to keep water below its 2014 water usage while wrestling with ways to meet that mark as the city’s population continues growing.
Woodbury utilities superintendent Jim Westerman predicted a 20 to 40 percent water reduction for residents participating in the program, enough to possibly convince others to see the value of smart controllers and water bill savings.
Lawn irrigation accounts for about a one-third of the city’s 3-billion-gallons-a-year water usage. The city also has to contend with increased demand in the warmer months by opening all 18 of its wells during that time.
Communities relying on water from the Prairie du Chien-Jordan aquifer-- which spans across much of Washington, Ramsey and Anoka counties -- may need to find another source in about 20 years if water usage continues at its current pace, according to the Minnesota Department of Natural Resources (DNR).
“It’s not just the city of Woodbury issue, it’s a regional issue,” Westerman said. “It’s not a crisis right now, but we want to be ahead of the game and take the right steps today.”
Though DNR data suggests aquifer levels beneath Woodbury have been relatively stable, Westerman said the city might need to find costly solutions such as building a new well or using river water if the aquifer no longer were an option.
For now, though, the city has focused its attention on cheaper solutions.
Westerman said the city tested a number of other smart controllers and found the Rachio model met the project's needs because they’re easy to install, cost $150 to $250, and do not carry a subscription fee.
“If things work out, I think that’s the direction we would like to see property owners go,” Westerman said. “The city’s role is yet to be be determined.”
The implementation pilot program is expected to wrap up by September. Westerman said the city will continue tracking the impact of new irrigation technology for several years.