Since mayor Tim Rogers first proposed leaving the possibility of exploring for water in the Millbrook Preserve open, the matter has been controversial. Last week’s meeting of New Paltz’s village board heard a detailed explanation of the process from Frank Getchell, senior vice president of a Connecticut firm, and one of his associates.
Actually drilling wells on the edge of the preserve is something that neither Rogers nor trustee Thomas Rocco, a supporter of the idea, believe would be affordable or necessary for the foreseeable future. They just don’t think it would be responsible to tie the metaphorical hands of future trustees and mayors by foreclosing on water exploration in the conservation easement now being prepared. As strongly as they feel about that responsibility, other trustees feel that such drilling would violate the trust placed in them to preserve the Millbrook. Most outspoken on that point has been Don Kerr.
It was Kerr who asked that additional hydrogeologists be interviewed, because he had concerns that the local ones would be deemed unsatisfactory by him or some of his colleagues. Getchell was the first to speak to board members. Kerr hopes to hear from more. Tom Rocco, for his part, described the presentation as “painful” because he’s been working closely on water projects for the past three years, and has so far learned nothing he didn’t already know.
Getchell explained the difference between aquifers found in bedrock and those in subterranean sand and gravel beds. The bedrock in New Paltz is of a sort where water would only be found in existing fractures, meaning that likely drilling spots would run in a fairly straight line. Science is used to determine the most likely orientation for such fractures. That includes looking at the topography and geology, but also at nearby wells to detect clues as to other places which might yield a productive well. Getchell called the overall process “fracture trace analysis.”
Sand and gravel deposits in the area of the Millbrook are significant, Getchell said, and could mask fractures from easy detection. It’s still possible to ascertain the orientation of a particular fracture, he said. That’s important to avoid “a situation of robbing Peter to pay Paul,” or drawing down wells tapped into the same fracture, what he referred to as “interference.”
Once it’s time to drill a test well, the operators examine the materials brought up carefully for clues as to what lies beneath. The drill pulverizes whatever it passes through and sends it back up the hole. The character of that material and back pressure from water can provide critical information about when it’s time to stop the rig. That’s often how a sand and gravel aquifer is discovered.
Wells in those draw water from a wider area, and could be better in some cases than a fracture well because of that. If and when water is located, a casing is put down the resulting hole and a pump installed. For sand and gravel wells, a screen is used to keep the well from getting clogged or the hole from collapsing.
Getchell thought that “even drilling blind” in or near the preserve would yield 20 to 30 gallons per minute. Some 620 gallons per minute is needed of a backup water supply for water district residents when the Catskill Aqueduct is shut down.
Kerr was skeptical about one thing Getchell said, that “you don’t know until you drill,” even after careful analysis. “Isn’t that just professional gambling?” he asked.
Getchell did not directly disagree, but noted that the method was “based on science.” Further pressed by Rogers, he said that he believed a quarter to a half of properties in New Paltz would yield usable wells.
Deputy mayor Rebecca Rotzler wanted to know the size of the equipment which would be doing the drilling. Getchell described a typical rig as shorter and wider than a tractor trailer, with a 20-foot mast needed to drill through rock. Trustee Dennis Young, who asked about the noise of the operation, was told that it would take about three days to drill the maximum 300 feet through rock, during which time there would be “drilling chatter” from the machinery. It would be quieter going through sand and gravel, but a slower process would take up to seven days.
In addition to lining up the hydrogeological conversation, Rogers did additional homework around water exploration in the preserve. DEC staffers are looking into environmental sensitivity along the western edge of the preserve, which is where drilling would occur under the current proposal. The mayor also visited Mohonk Mountain House to get an understanding of how water is obtained among some 8,000 preserved acres. He learned that, as with the village supply, where the water’s obtained depends on the time year. Guests drink water that’s 100 percent from the lake during February, when the turbidity is low enough to treat, while two springboxes installed in 1926 provide their best yield once the thaw comes.
Two miles from the hotel itself are two bedrock wells, each 300 feet deep, rated for 50 and 90 gallons per minute respectively. A third well is expected to be needed in the next few years, Rogers also learned.
Join the family! 
