Heat Wave, Sprinklers Sap Town Water Supplies

Sweltering temperatures parched throats and lawns this week, but it's the latter Water-Sewer Superintendent Joe Duggan is worried about.

Wellesley's been using up water steadily since Monday, so much so that the DPW has had to send letters and reverse 911 calls to residents asking them to stop outdoor water use. At least, that is, until the next rain.

Duggan said the town has a five-tier system for assessing Wellesley's water supply. One is normal. Five is emergency. At the moment, he said, the town is at three, a water-watch. That calls for a voluntary halt to use of water outside the home, though hand-watering of plants is OK. At Tier Four, the town issues a warning for outside watering on the first offense, then $50 for a second offense and $100 a day after that.

"We've never had to go to that," said Duggan.

The National Weather Service forecasts some rain today, showers and possibly a thunderstorm after 3 p.m.

As for what caused the shortage, Duggan said he suspects lawn watering. "It hit us in a hurry," on Monday, he said, when water use started draining supplies around the clock. That was also the third day of a heat wave begun over the weekend that caused electricity use to spike. 

The time of day when the most water is being used, he said, is at 4 a.m., the prime time of the day for lawn watering. "It's about the horticultural best-fit," Duggan said, the perfect time for gardeners to water plants and lawns, when most automatic sprinkler systems are set to begin.

The town's water supply is pretty flexible, Duggan said, with some of the supply coming from the Massachusetts Water Resources Authority (MWRA) and the rest from seven town wells feeding three water treatment plants. But heavy use can exhaust it.