There is no drought on Martha's Vineyard. While dry conditions may continue in other parts of the Northeast, the Vineyard has had healthy rainfall thus far this year.
But despite spring rains, Vineyard ground water levels are at or near their 25-year low. This has raised concerns that homes in outlying areas, those with wells near the coast, may be vulnerable to saltwater intrusion.
Earlier this month the state Emergency Management Agency and the Executive Office of Environmental Affairs lowered the statewide drought watch to a drought advisory. In a joint press release, the two agencies declared: "Stream flows were at normal levels across the state, and ground water levels were mostly in the normal range. Some areas in the central, northeast and southeast regions of the state remain below normal. The Cape and Islands continue to have below-normal ground water levels, a situation that has existed since June of 1999."
From January through May of this year, rainfall for the Vineyard was close to the historic average. In the first five months of 2002, the Island received 23.27 inches of rainfall, slightly more than the average for this period. The annual average is 45.82 inches.
Kimberly Buttrick, a meteorologist for the National Weather Service in Taunton, said yesterday: "During the past three months, from March through May, precipitation has averaged from normal to above normal across all of Southern New England.
"During the month of May, not only was it above normal in rainfall but below-average temperatures were noted. Below-level temperatures helped to reduce the evaporation, which helped lessen the impact of the drought," Mrs. Buttrick said.
She added, "May precipitation totals ranged from 4.5 to 6.5 inches across the majority of this area, which is 125 to 175 per cent above normal, with the exception of Nantucket and Martha's Vineyard, where they received three to four inches - that is about 90 to 100 per cent of normal."
With nine days left in June, the Island has already received more than the average. The National Weather Service cooperative station in Edgartown has so far recorded 2.94 inches of rain. The average is 2.65 inches.
May was wet, though not enough to meet the average. May rainfall total was 3.89 inches, .36 inches less than average.
William Wilcox, water resource planner for the Martha's Vineyard Commission, has been keeping track of wells across the Island to gauge the ground water aquifer. At the Manuel F. Correllus State Forest, there is a well that Mr. Wilcox has monitored for 25 years.
The water elevation in relation to the height of sea level shows the size of the aquifer. The historic average is 15.6 feet at that state forest well. Mr. Wilcox said that this May it was 12.8 feet above sea level. "It is still lower than normal. We need a couple of feet of recharge. We won't get that unless we have a monsoon summer. We are right now entering that period of the year when we don't get much of a recharge, because plants soak it up and it also evaporates into the air," Mr. Wilcox said.
"The water table should continue to decline right through December before it turns around," Mr. Wilcox said.
"Last March, the ground water table at the well was the lowest in the 25 years of recordkeeping," he said.
That is a concern for anyone living near the shoreline. Mr. Wilcox said that people with private wells near the shoreline might experience some saltwater intrusion. This occurs when the well is pumping water from the aquifer and is bringing in saltwater. Typically the lens of ground water is thick enough to keep the surrounding ocean at bay.
The state advisory warns: "Homeowners and other water users are advised to follow any guidance and adhere to any restrictions that may be put in place by their local water supplier. Care should be taken with outdoor fire uses. Homeowners and other facilities with private wells are advised to monitor local conditions accordingly."
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