New Brighton is stepping up water restrictions this summer, concerned that the aquifer the city is drawing from may be unable to meet peak summer water demand starting next month.

Earlier this month, the City Council unanimously approved a water conservation plan that limits lawn watering citywide.

While many metro area cities implement similar water restrictions, New Brighton was forced to make the change this ­summer after years of having an abundance of water for the town's roughly 21,000 ­residents.

"We've had so much water, we'd give it away," said City Council Member Gina Bauman about such neighboring cities as Fridley tapping into the New Brighton's aquifer. "We've had ample water and too much water. … It was a luxury."

But in April, the north metro suburb shut down its aquifer after trace levels of a contaminant were discovered. Chemicals used at the former Twin Cities Army Ammunition Plant in Arden Hills are the probable source of the contaminant, though the amount of the chemical — 1,4-dioxane — found in the city's wells is so minute that the city said residents would need to drink 2 liters a day for 70 years to have a heightened health risk.

Still, the city took precautions, closing the aquifer and starting to draw water from deeper wells in a separate dioxane-free city aquifer. That second aquifer, however, holds less, about 4.5 million gallons of water. City leaders fear it may not be able to handle possible peak demand — up to 6 million gallons of water a day — during July and August. Typically, the city uses about 2 million gallons a day, city staff said.

"We have to be cognizant and be proactive in case something does happen," Bauman said. "I don't see a danger of it, but we just have to be careful."

As a result, the city started clamping down on water use this month. The restrictions allow homeowners with odd-numbered addresses to water their lawns on odd-numbered days while even-numbered addresses can water on even-numbered days. If further restrictions are needed, the city could prohibit sprinkling lawns between 6 a.m. and 9 p.m. and forbid residents from filling pools or washing cars. The city is issuing warnings to residents and businesses, but Bauman said so far no one is reportedly violating the rules.

The city is sharing the burden by not watering city ­property, with a few exceptions, such as softball fields.

The restrictions could be a new way of life for New Brighton residents and businesses. That's because the city and the Army are working toward a permanent solution for ­filtering the system, but Bauman said a fix could take five years.

For more of the city's tips on how to help conserve water, go to ci.new-brighton.mn.us.

Kelly Smith • 612-673-4141