This story was first published at KUNC News.

AURORA | Tim York sees Aurora residents watering their lawns on those extra days when they aren’t supposed to, even when their illegal watering happens at 4 a.m.

York doesn’t actually see the violations with his own eyes. But the leader of Aurora’s water conservation program knows they’re doing it with the help of a new computer program.

“We look at about 2.2 million data points for each individual day, so we’re looking at hourly water use data, and we built some scripts that run against that data on a weekly basis to say “was somebody irrigating when they’re not supposed to be?”” York said earlier this month at his desk at Aurora’s water operations facility.

With a few clicks of his mouse, York zeroed in on one of the thousands of watering violations recently committed in Aurora. A graph on one of his large LCD screens revealed a repeating pattern four days a week very early in the morning. He said it could only be a sprinkler on a timer.

This surveillance is powered by smart water meters installed last year on homes in Aurora. They transmit data every 15 minutes via cell signal. York’s team automatically gets a spreadsheet each week of thousands of likely outdoor watering violations. Humans verify the data before sending warnings or fines.

“If they say “there’s no way I irrigated,” it’s like, well, this is what (the data) shows, and then they usually agree,” he said. “We’re not picking on people just to pick on them. We’re addressing violations, and the reason we’re doing it is a good reason. Water supply is very, very poor.”

Aurora’s supply is currently only about half full, and dropping. It’s usually still filling with snowmelt this time of year. So the outdoor watering restrictions limiting outdoor watering to two days a week are mandatory. And with help from the new computer system, York said outdoor water usage is down 20%.

Warnings for overwatering have more than doubled over last year. Fines have skyrocketed too.

Millions of Coloradans remain under strict water restrictions because of historic drought. Failing to conserve could mean empty reservoirs, and even harsher restrictions.

Mehdi Nemati, a professor of environmental economic policy at the University of California Riverside, said mandatory restrictions like the ones being used in Aurora can be “highly effective” at reducing outdoor water use for a short period of time.

He says studies he’s analyzed through 2022 show restrictions around the West have reduced overall water usage about 12% around the West. But some cities are better than others.

“If it’s voluntary versus mandatory, mandatory ones are effective mostly,” he said. “Voluntary ones we don’t find really (have) much effect.

He says cities turn to the restrictions to prevent Day Zero, when water doesn’t come out of the tap.

“You don’t want to get to a situation that you start to ration water, including indoor water use,” he said. “We have seen this in places like Spain or Cape Town, where they get too close to Day Zero.”

Meanwhile in Denver, customers are also facing mandatory outdoor water restrictions for the first time in more than a decade. But Denver’s enforcement relies much more on people than computers.

“Drought tends to be this slow-moving emergency, and we have to ask our customers to stick with us for months and months, literally,” Greg Fisher, Denver Water’s manager of demand planning, said. “And I think our job is to help them not grow weary of saving water.”

If customers don’t comply, a new tipline is letting neighbors snitch on each other for wasting water. More than 2,200 complaints have been filed since it launched this spring.

“All of us have that one house, probably in our neighborhood, where you’re like, “oh my gosh, they’re watering every day,”” Fisher said. “That’s what this is for, is just to either hold them accountable or at least educate and say, “you know, it’s different this year.””

But does it really matter if a resident waters one or two more days than they’re allowed to? Back at Aurora Water’s HQ, Tim York gives an unequivocal “yes.” And he has data to prove it.

“We did this little run of data, and this was through June 2, and what it showed was that those who were watering three or four days per week use 41% more outdoor water than those watering two days per week or less,” he said.

But for all the help computers are giving Aurora, its water future is still in the hands of Mother Nature. York says monsoonal moisture could help boost the water supply. But more drought could force the city to move to stage 2 restrictions, limiting outdoor watering to one day a week.

This story was made available via the Colorado News Collaborative. Learn more at https://www.google.com/url?q=https://colabnews.co&source=gmail-imap&ust=1784923168000000&usg=AOvVaw2_051gEq0JX0YGaQvuLV0k

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