Friday, March 22, 2002
Water, wells and the drought: How is Carlisle faring?
It's been one of the driest seasons on record with little rain and snow falling over the past fall and winter. The state is now on a drought watch with much of the East experiencing extremely dry conditions. It's hard to ignore the drought now that spring is here. With "leaf-out" and the growing season beginning, plants are about to take up what little moisture is available on the surface.
Carlisle and its private wells have fared well so far during this unusual cold-weather drought. The board of health (BOH), which has jurisdiction over private wells, has not received any calls from homeowners about wells running dry so far this year, says BOH agent Linda Fantasia. She remembers a drought in the mid-90s when some wells ran dry and had to be deepened or a new well drilled.
If the dry weather pattern continues into spring and summer there could be problems with area wells. However, Roger Skillings says groundwater tapped by deep wells is not affected by drought, except over a very long period of time. "We've never had a well that is in excess of 200 feet go dry because of a drought. You may have a slow-down in the volume of water, but it's unlikely that you will run out of water completely."
Nancy Bryant, executive director of SuAsCo, the Sudbury, Assabet and Concord River conservation group, says she is also aware that many shallow wells in the region have been running dry. "Well drillers are doing a good business right now," she says.
No well problems so far
Town well inspector Ralph Metivier hasn't seen any increase in calls about wells yet this year. Wells are being drilled for new homes, he says, or when an existing home needs to move its septic field to a new location, causing the well to be relocated to meet the 100-foot minimum distance required between the septic field and a well. Information on wells that may run low or out of water is harder to obtain. When the seal is opened on a well, the drilling and pump company needs to obtain a board of health permit to repair the well, though actually the board is not notified of every repair.
Mark Duffy of Great Brook Farm says soil on the farm is "extremely dry" right now and ponds are also at low levels. Great Brook Farm has a deep well with good flow and Duffy hasn't had a problem with the water supply for the cows. He irrigates the fields of sweet corn grown for sale at the ice cream stand, but silage corn grown for the cows depends mostly on rain and ground moisture, with only occasional irrigation. "I don't like to start the planting season dry. There's not much water in the soil," he said.
David Flannery, superintendent of buildings and grounds at the Carlisle School, reports the school has an excellent water supply due to a 400-foot deep well that can provide 16 gallons a minute. The municipal well was drilled in the late 1960s at the school. On one occasion last fall the school ran out of water by the end of the day due to an unusually high water demand and limited water storage. "The problem was that we reached our storage capacity limit of 4,000 gallons in our storage facility and we couldn't keep up with the demand," he said.
The Massachusetts Department of Environmental Protection (DEP) recommended that a second well be added as a back-up source of water, something that is not in immediate plans but is in long-range plans for the school, says Flannery. Where to locate it on the campus is an issue because new state regulations, since the old well was put in, require wells to be set back from surrounding parking lots and buildings.
There are no guarantees when it comes to finding water. Skillings drilled multiple wells before finding water on some new home sites on Hutchins Road in recent years. Well-drilling companies offer hydrofracturing to home-owners as one way to increase water supply. Hydrofracturing, where chlorinated water is pumped into a well under high pressure, is done to open fractures in the bedrock to improve the flow of water to the well.
Ground water low
Five town wells were drilled over a decade ago to monitor ground water levels in different parts of the town with different soil conditions. The wells are measured weekly by an engineer hired by the town. They are located on Cross Street, Towle Field, Blaisdell Drive, Fox Hill and Foss Farm.
March and April are high-water season for the board of health, with the ground water measurements collected at the wells used to calculate new septic field construction and placement. Recent test results indicate ground water levels are much lower this year than last. February 15, 2001 ground water depths at the five wells were: 4.1', 7.3', 5.2', 10.8' and 19.2'. February 28, 2002 depths at the same wells were: 11.4', 12.9', 7.2', 11.5' and 21.3', respectively.
Town well sites explored
Tony Mariano, Sr., a geologist and member of the BOH water quality and resources subcommittee, has explored the town-owned O'Rourke Land on Maple Street as a possible site for future town wells. The property has a glacial outwash plain, a natural resource which could provide a large supply of water, that can only be found in certain locations. Because of proximity to private lands, only limited areas of the O'Rourke Land are available for town use.
Currently the town is not pursuing a community well, but Mariano says, "Who knows how things will develop as the population gets denser? There can be an increase in contaminants due to septic systems, or some type of pollution can develop. With private wells and private septic systems we have a delicate situation."
Development can impact supply, he says. "The aquifer may lose some volume as homes are built if they are tapping the same aquifer." Some homes have had a decrease in water volume and quality believed to be related to nearby construction.
Concord, Acton, Bedford and Westford have town wells to serve the needs of residents. In towns with community wells, problems arise in summer when demand is high and towns often impose water bans for homes in summer, restricting outside water use to every other day. Some home-owners drill private wells on their property to ensure they have enough water for lawns, gardens and pools. Signs that say "Well water in use" have appeared in yards in other towns to indicate they are using a private water supply.
Share the aquifer
Automatic lawn irrigation systems are becoming standard at many new homes, but Skillings says they don't cause problems with water supply in a neighborhood, as a rule. "But I'm not going to say it can't happen," he says. Different homes in a neighborhood can be drawing water from the same fracture in the bedrock, something that is not usually known until there is a problem with supply.
Underground water is drawn from small fractures deep in the bedrock that can run for long distances. Skillings has seen situations in other towns where one home with a lawn irrigation system didn't have outside water until their neighbor shut off his sprinkler system, indicating their wells share the water supply. Even though automatic sprinklers in an area can affect supply, he says, "You may run low in your supply, but you won't run out of water."
The Malcolm Meadows housing complex on Stearns Street had a supply problem two years ago when a sprinkler system there caused a well to run dry, a situation that has since been resolved, according to Fantasia.
The board of health has well-yield regulations as part of its water supply regulations for domestic water use. For sprinkler irrigation systems the board can give guidelines with recommendations for home-owners, but it does not regulate outdoor water use. The board recommends a well yield of a minimum of 10 gallons per minute to run a lawn irrigation system.
Conserve water this summer
Though home-owners don't have to pay a water bill in Carlisle conserving water makes good sense, especially in a drought. Rains may pick up this spring, however the rainfall isn't likely to be enough to replenish water supplies. Besides, ground water for wells, surface water in ponds, lakes, streams and rivers are also at low levels, says SuAsCo's Bryant. "Everybody needs to chip in for the common good not for the individual good when water is scarce and we are sharing the same resources this summer."
"Everyone is entitled to a fair amount of water from the aquifer, but not an excessive amount," says Skillings, "If it affects somebody else, it's not right. Keep in mind that water could be coming from other properties, not just your own." He recommends watering lawns every other day early in the morning to cut down on evaporation and to prevent lawn diseases.
Water committee member Mariano takes a different view, "In a drought, watering lawns could be a luxury we cannot afford," he says, noting that Carlisle is lucky because many homes have kept their woodland settings and have smaller lawn areas.
Water quality testing
The Carlisle Board of Health will offer voluntary well water testing in May. Homeowners can have their well water quality tested by a private laboratory, at a volume discount offered to the board of health. This is the third year the board will offer water quality testing. Specific dates and other information will be published at a later date.
Keeping your well well
Scott Wilkins of Skillings and Sons suggests that a routine maintenance check be done by a well company about every five years, including checking the following:
· the pressure switch to make sure the pump is not starting and stopping excessively. Replacing the switch every five years will prolong the life of the pump;
· the air capacity of the storage tank to make sure the pump is not turning on and off unneccessarily;
· the pump's electrical functions, using a meter.
Other steps that can prolong the life of the well pump include installing:
· a larger water storage tank, so the pump motor works less hard;
· a low-water protection device to shut off the pump if the well runs dry. This protects the pump motor especially with low-yielding wells.
In addition, homeowners should have a basic water quality test done every two years and a more extensive quality testing every five years. Prospective home buyers should have a well contractor test the well water for quality and supply..
© 2002 The Carlisle Mosquito