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Drought, Deluge, and Debby
Drought, Deluge, and Debby
By John E. Ross
Bone dry, August opened with local gardens wilting. On a few trees, leaves were already yellowing and beginning to fall. Three weeks earlier, Middleburg, nearby towns, and surrounding counties had ordered mandatory restrictions on outdoor water use. Among suggested indoor water conservation measures was turning off the tap when brushing your teeth.
Everyone in drought’s talons felt a breath of hope when Hurricane Debby, with its heavy downpours, turned inland on August 8 and began to follow the Appalachians northeast. Surely, Debby’s deluges would bring drought relief.
As Debby was delivering its much anticipated rain on the night of the 8th, cell phones, TVs, and radios buzzed like angry rattlesnakes on steroids. Emergency broadcasts warned of probable tornados. Sure enough, shortly after 9 p.m. a tiny tornado touched down at Willisville and tracked northwest for about five miles, clipping tree tops and cresting the Blue Ridge just south of Mount Weather.
The heavy downpour continued throughout the night. Before Debby, Goose Creek below Crenshaw Road bridge had been flowing gin clear and barely ankle deep. Now the creek was flowing bank full and colored like heavily creamed coffee. Surely, two to four inches of rain in twice as many hours depending on location, would loosen drought’s claws.
Alas, not so. Deluges do little more than green our grasses and water our gardens and crops. Most drinking water in ZEST’s circulation area comes from ground water trapped deeply in fissures in bedrock barely affected by deluges and run-off. As Danny Davis, Middleburg’s Town Manager put it, “Five inches of rain in an hour may add a little to our water supply, but one inch over five hours or an inch a day for several days can help a lot.”
We depend on wells for potable water. About 20,000 private wells provide water to residents of Loudoun County with thousands more in Fauquier County. Most area residents rely on commercial wells feeding public water supplies. Virtually all wells tap groundwater held in fractured granite and gneiss bedrock.
Gone are old historic wells dug by hand, and few wells today tap groundwater held in soils overlying bedrock. Underlying geology and fractures in that rock determine well yield. Productive wells are those providing more than five gallons per minute.
Yield depends on where one drills. In Waterford, for example, one well 200 to 300 feet deep produces an ample flow. Nearby, another landowner had to drill 1,110 feet to generate similar yield.
Precipitation falling on the flanks of the Bull Run Mountains to the east and Blue Ridge to the west very slowly recharges water-holding fractures tapped by most wells in the valleys between Aldie and Paris.
However, rain and snow melt do percolate very slowly down through soils and eventually into the water table. Soil is an extremely effective water filter, said Jason Purdy, an environmental scientist with Loudoun County’s Health Department. Not only does soil prevent solid particles from entering the water table, but oxygen and microbes held between grains of soil have the capacity to cleanse surface water of disease pathogens.
Until recently, drain fields attached to septic systems were thought of merely as a way of getting rid of household effluent. Now, a drain field is considered to be “an elegant form of water recycling,” according to Purdy. For household use, he said, we’re merely “borrowing” the water. It’s hard to think of a drain field as elegant.
With the onset of Middleburg’s outdoor water restrictions, we installed a 50-gallon rain barrel at our Middleburg home. Why allow rain to run off into the street when it could be used to water plants and shrubbery? The rain barrel cost about $200, with installation around $300.
While rain barrel water is fine for watering plants, it’s generally not safe to drink. Rainwater contains a variety of pollutants like fine particulate ash from wildfires and related substances known as “forever chemicals.”
The good news: despite drought over the last several years, water supplies appear ample for at least the next decade. Danny Davis said public wells can produce about 400,000 gallons per day. While drought has depressed the water table somewhat, current use is running about 120,000 gallons per day. Still, with climate change producing more intense periods of drought and deluge in the Mid-Atlantic states, water conservation is becoming more and more critical. What to do? In addition to installing rain barrels, one can also establish rain gardens to capture stormwater runoff from driveways and patios and use pervious materials when paving or repaving.
YES, THERE WAS A TORNADO
Cyclones commonly fringe hurricanes moving northeast along the Blue Ridge. That I knew. But my complacency was utterly shattered when a tornado touched down five miles away at Willisville a little after 9 p.m. on August 8.
A couple days later I drove north on Trappe Rd. from Upperville to see its path of destruction. Near the entrance to Cleremont Farm, workers were cutting up downed trees. South of where the tornado crossed the road, felled trees pointed to the northeast. North of its track, downed trees pointed southwest. The tornado’s counter-clockwise rotation was clearly evident.
Along the road, the zone of broken branches ran about half a mile. According to NOAA, the tornado’s path was about 100 yards wide and its track, 4.7 miles long. Maximum winds are estimated to have been about 100 mph, an EF-1 storm. Fortunately, no one was injured and damage to buildings was light.
Danny Davis, Middleburg’s Town Manager, reported that Loudoun and Fauquier counties’ emergency services are prepared to coordinate the town’s, county, and state fire and rescue operations should a tornado hit a community.
On average 18 tornadoes strike Virginia every year. No longer complacent, to prepare for future tornado warnings, at our house we’ve stocked a few gallons of water and additional emergency backups for cell phones.
—John E. Ross
