High Temperatures, Low Rainfall Raise Drought Fears

July 16, 2010 — Below-normal rainfall and above-normal temperatures led the Virginia Department of Environmental Quality to put the entire state under a drought watch earlier this week.

"Since March, the precipitation levels have dropped significantly for most of Virginia," University of Virginia climatologist Phillip J. "Jerry" Stenger said. "In April, most areas received less than about 50 percent of normal and May rainfall was quite variable between locations. A persistent ridge of high pressure has suppressed rainfall from June through the present."

At the same time, temperatures have also been running above normal statewide. For many days, high temperatures were 10 to 20 degrees above normal and a number of records were set.

"The shortage of rain contributes to this, because less of the solar energy is used to evaporate surface moisture and more is available to raise air temperatures," Stenger said. "In turn, the higher temperatures increase the loss of moisture."
 
Reservoir and groundwater levels are not dangerously low, according to Stenger, who noted precipitation throughout the commonwealth was significantly above normal last November through March, critical months for recharging groundwater.

Tropical storms, a traditional source of summertime precipitation, have yet to affect the state.

"This hurricane season is forecast to be an active one," Stenger said. "But, so far, only one named storm has formed and there is no significant activity in the tropics."

Drought conditions are stressing the University's plants, landscaping superintendent Richard M. Hopkins said. He said the heat and lack of water have joined the snowstorm and microburst damage in devastating the University's plantings.

"We're losing plants because of the lack of the rain and the heat," Hopkins said. "These things are hard on the landscape."

Most landscape watering is conducted between 5 and 9 a.m., with the exception of a few places where landscapers are trying to get new sod established, such as the McIntire Amphitheater and outside Bavaro Hall. Deep-root watering, required by some plants, is usually done at the end of the day when it is cooler. Some trees and shrubs requiring water have drip bags from which water slowly seeps into the soil.

Landscapers use non-potable water from holding ponds for irrigation. Recent renovations at the McIntire Amphitheater added a 7,200-gallon cistern to collect rainwater for central-Grounds landscaping use.

While the University has been slowly shifting toward planting more drought-resistant species and varieties, this year's weather extremes have been too much for some of the plantings.

"We're losing some plants that have been here five, 10, 30 years," he said. "There are places where we are letting the grass go."

Apart from landscaping, the University has been working on conserving water in many other applications around Grounds.

"We're not doing anything out of the ordinary now, because we are trying to conserve water all the time, not just when there is a drought," said Paul Crumpler, an energy engineer with Facilities Management's utilities department.

The University is expanding its chiller processing facilities in the Chemistry Building and Wilsdorf Hall to handle more equipment.

"We are recovering condensation from air handlers in Chemistry, about a million gallons of water a year, which is re-circulated into the system," Crumpler said.

There are also old-fashioned approaches.

"We are always looking for leaks," Crumpler said. "We are looking for water that is out of place. We look at water bills to see if use has gone up. A lot of times, leaks are hidden."
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-- by Matt Kelly