Better plumbing, less lawn care have fed multi-year decline, observers say.
Different measures are available for the two cities, but they both show the same strong trend over the past 15 to 30 years:
In Minneapolis, consumption dropped 17.2 percent from 1998 through 2007, a time when the population was virtually unchanged. In August 2011, a dry month, the city used 31 percent less water than it did in August 2006, a wet month. And in 2011, Minneapolis residents and businesses used 378 million fewer gallons than they did the year before.
In St. Paul, daily average water use dropped nearly 21 percent from 1980 through 2011. Peak use during that period was in the drought year of 1988.
Observers point to several contributing factors:
Conservation and technology. Contemporary plumbing fixtures -- low-flow shower heads, dual- and minimal-flush toilets, faucet aerators --have combined with changing attitudes (think: shorter showers) to reduce water use. Moisture-sensitive automatic sprinklers are preventing instances of sprinkling during rainstorms and wet periods. And Minneapolis parks workers are able to target their sprinkling on golf courses using remote, web-based technology, said Parks and Recreation spokeswoman Dawn Sommers. Further innovations mean water use is likely to keep declining, added Rachel Maloney, owner and founder of Natural Built Home in Minneapolis.
Landscaping. One-third of all residential water is used on the lawn. But that also might be declining as less thirsty native plantings become more popular, and both young and elderly homeowners -- not to mention corporations and public agencies -- show growing disdain for big-time lawn maintenance, said Roy Robinson, owner and manager of Landscape Alternatives in Shafer, Minn.
Jim Graupmann, production division manager of St. Paul Regional Water Services, who has worked for the city for 30-plus years, said the trend toward less water use has become obvious during dry periods. "In some parts of the city you can bike a long way before you see a green lawn," he said.
More rain. Normal annual precipitation in the Twin Cities is 1.2 inches greater than it was for the period 1971-2000. The gain for June through September alone was .55 inch.
In suburban Andover, as the population almost doubled from 1991 through 2007, water use grew sevenfold. But since 2007, while the population has remained flat, water use has declined 22 percent.
In that Anoka County city, big lots mean that lawns drive water use. Andover uses five times as much water in mid-summer as in January -- one of the widest disparities between those two seasons in the metro area, said Brian Kraabel, the city's utilities manager. But that's coming down, he said, because of watering restrictions, education and an increasingly wet climate. "We want to think people are being educated and are starting to get to know we need to protect the water system, and just use water wisely," he said.
A bottom-line difference: In 2011, homeowners and businesses in Minneapolis paid about $2.2 million less for water than they did in 2010. That also means they paid less in sewer charges to get rid of water they've used, noted Bernie Bullert, director of water treatment and distribution services for the city. "It adds up," he said.
Bill McAuliffe 612-673-7646