Naples strikes it rich with aquifers

By Dawn De Busk

Staff Writer

NAPLES — Certified geologist and hydrogeologist Rick Pershken said he felt like he had struck it rich when he found three high-producing wells with quality drinking water in Naples.

“It has been a lot of fun, especially when you go three-for-three. Maybe, I should buy a lottery ticket,” he said.

Not only did Pershken consider himself lucky to locate excellent aquifers, but also the Town of Naples could benefit from a protected, top-notch source of public drinking water.

On Monday, two representatives from the James W. Sewall Company presented to the Naples Board of Selectmen their findings after drilling for water at three test sites. The hydrogeological work took place this past autumn.

Two of the potential wells were located at Sebago State Park property accessible off Thompson Point Road; on land owned by Hancock Lumber Company and situated near the Crooked River off Cooks Mills Road; and on privately-owned land that was once used as a sand and gravel pit.

The third parcel is located off Songo School Road at the end of Burnham Drive, which turns into Oakwood Circle. If developed as an aquifer, that property, which is owned by Bob Mason, could supply water to the Songo Locks School. The well water at the school has tested positive for radon levels.

“We have excellent news for the town. We have found three promising well sites,” said Sewall’s Director of Water/Wastewater Services Michael Riley.

“We are here to share what we found from our hydrologic study,” he said, adding that the next step is for the selectmen to decide which site they are most interested in developing.

The Sewall employees will finish up the report and present that paperwork to the selectmen in a few weeks.

Costs are involved in setting aside drinking water for the public, and those costs include purchasing easement property, paying for underground water pipes and constructing a water storage facility.

For now, the official completion of the public drinking water study will allow the town to get approval from the state, and to go forward with applying for any grants to help with the project.

Pershken said his first recommendation would be the Hancock Lumber property “because of its relative closeness to town” and the company’s willingness to enter a land conservation contract.

His second choice was the Sebago State Park property. Even though it is farther away from Naples’ existing water lines, it will be easier to protect the water on that parcel, he said.

State officials have expressed to Town Manager Derik Goodine an interest in selling the land to the town. Controlling the property around the well would allow the town to preserve its aquifer.

Protecting the wellhead is an important factor when selecting the location for a public water supply. The protected space should be about 300 feet around the well, where nothing is developed and nothing already exists that might taint the water. Also, the areas should be able to supply 300 gallons per minute without affecting the water levels.

A comparison chart included other valuable data, such as the distance between the potential well and existing water pipes, how many lots would be served if the well was in operation, and the space between the well and the nearest lot.

For example, the former gravel pit referred to as the “Mason property” is 12,000 feet away from town water pipes, 81 feet from the nearest lot and, if installed, would service 148 lots.

The Hancock property is located 12,500 feet away from a water line and 89 feet away from a privately-owned parcel, and would hook up 141 lots to good drinking water.

Located the most distance from town-owned water lines, the state park property would require 18,800 feet of pipe, with the nearest lot 97 feet away. If that aquifer were developed, it would service 193 pieces of property that are currently not on town water.

Pershken said the greater distance from main line could be cost prohibitive, especially when factoring in the additional cost of constructing a water storage tank. He recommended an underground concrete facility because it is less expensive to build and requires less maintenance.

Pershken explained the method used to test-drill the aquifers.

Workers use two 2½-inch casings, which were driven into the ground by a mobile drill rig. The casings were flushed with water. Workers collected samples of the sand and the water for later laboratory testing, he said.

“The drill rig that was used to put in casing, it drives the casing into the ground. It is very simple and a fairly inexpensive rig to get in there without building a road,” he said.

For the first round, the test well runs for four hours, and then workers measure the drawdown or the amount that the water level decreased after continuous operation. The optimum water flow is 300 gallons per minute, with a drawdown of less than one foot.

If more testing were required, the company would get permission from abutting neighbors to check their wells for drawdown.

The deepest drill happened on the state park parcel, with the drill hitting glacial till at 77 feet. Once the location of a glacial till is established, the casing is set above it to get cleaner water. At the other two sites, the casings went about 50 feet down before reaching cobble.

Both Riley and Pershken praised the three locations equally for the quality of water and the sustained water pressure.

“These are some of the most productive sites I have seen in Maine,” Riley said.