Conservation Commission considers water improvements
By Doug Grindle Community Reporter

Marlborough - At its meeting July 5, Marlborough's Conservation Commission considered a project on Maple Street designed to improve the water flow around the city.

The project involves improving water flow along Maple Street as part of the upgrade of the Maple Street pumping station.

The pumping station is being upgraded to handle an increase in water flowing from the neighborhood of a new 332-unit development being built on the Southborough town line by Fairfield Residential of Texas. The new units will help satisfy the city's requirement for low-income housing.

As part of its development, the city has directed the company to send water from the west side of the city to the east side, to ease the burden on the westerly wastewater system. Upgrades to the pumping station will help make that possible, said Edward Clancy, the commission chair.

The commission looked specifically at improvements running alongside Maple Street that are linked to the overall design to upgrade the pumping station there. The design firm hired by Fairfield, Tetra Tech Rizzo of Framingham, presented a plan to the Conservation Commission that would help speed the flow of water along the street.

The plan involves creating several channels traveling through the nearby wetlands on the bed of an existing brook and constructing an underground bypass chamber to ease the flow of water.

The commission has seen several versions of the plan so far, and members voiced several concerns.

"We were concerned with the tank floating," Clancy said.

He noted the water table in the area is near the surface and the bypass chamber would be 18 feet tall, buried in a hole approximately 20 feet deep.

"You're beefing up the weight to keep it from floating," said Brian Sullivan of Tetra Tech Rizzo.

Commission members also said they are concerned the size of the hole may not leave enough space for the construction work. The work site is near Maple Street, a fiber optic line, a gas line and wastewater line.

"Can't you move it back?" Clancy asked.

Assistant City Engineer Tom Temple said the space is too tight to move the hole.

"We like to maintain a 10- foot horizontal separation between utilities," he said.

That separation does not allow for the bypass chamber to be moved any farther from the road, he said, because of the other utility lines surrounding the site.

The commission also asked about the effect on the nearby wetlands. Clancy noted the site in the past had been well maintained by the city, although it has fallen into disarray in recent years.

Brendan Quigley, a Tetra Tech Rizzo scientist, said the digging at the site had already aff ected part of the wetlands, but when the project is finished most of the wetland areas would retain their original form.

"The two permanent impacted wetland areas are at the concrete outflow structures," Quigley said.

The outflow structures help move water across the site.

The commission directed the designers to come back to its Thursday July 19 meeting with revised plans.

Temple noted the construction work on this part of the project would take 15 weeks.

"You'll be done by Christmas," Clancy said.

Other business

The commission was to hear amended plans for the Mauro Farm site at 150 Cook Lane, where developers are hoping to build 27 houses on 16 acres of land.

The developers did not present their latest plan at the July 5 meeting because the city's Engineering Division is reviewing them, Clancy said.

Developers need to have any plans approved by the Conservation Commission, the Planning Board and the Engineering Division of the city's Department of Public Works.

Clancy said the Conservation Commission gets involved in only wetlands issues.

"That's the only thing we discuss," he said, adding that other aspects of any plan must be reviewed by the Planning Board.