Brookline Dam One Of 39 In MA In Poor Condition: Report

BROOKLINE, MA — Some 39 dams across Massachusetts are in poor condition and increasingly at risk of failing as climate change brings heavier bouts of rainfall. Many of these dams are in populated areas where, should they fail, at least one person would likely die.

Until recently, that category included a Brookline dam — the embankment running along one side of the Brookline Reservoir off Route 9 near Warren Street.

In 2014, the state Office of Dam Safety determined that the dam, built in 1848 to hold drinking water for the area, could pose a danger to several nearby homes because of trees that have taken root in it.

Although many of the trees had been there for decades, the state says trees should not be allowed to grow on or within 20 feet of a dam: “Tree roots cause serious structural damage to earth embankment and appurtenant dam features such as gate wells, spillway walls and other components.”

The Brookline Reservoir was listed in the town’s long-range Capital Improvement Plan for renovation, originally including improvements to footpaths and plantings and construction of a public restroom. But the scope was widened in 2014, when the town found out the dam could pose risk to lives and homes if more thorough work was not done.

The Office of Dam Safety asked Brookline to remove all trees and shrubs on top of the dam and plant grasses that can be mowed periodically to allow for visual inspection of the dam. The aim is to maximize structural stability that could be compromised by uprooted trees, penetrating roots and burrowing animals.

The Parks and Open Space Division worked with state officials to develop a plan that could ensure the integrity of the dam while maintaining some trees, particularly cherry trees growing above the water elevation.

How's Brookline doing?

Work on the park started this spring, and included everything from pulling up trees to draining about half of the water to work on underwater valves beneath the gatehouse.

The town is now more than halfway through a $3.1 million project that grew to include a renovation of the reservoir park and gatehouse.

The town had to remove all trees by the main gatehouse at Route 9, remove all trees in fair or poor condition, remove all "understory" plantings and commit to a monitoring program, according to Brookline Parks and Recreation Director Erin Gallentine.

"The Town is absolutely taking the proper steps to protect the community from loss of life or serious damage to homes, medical facilities and commercial developments," she told Patch in an email. "In addition to tree removal, dam stabilization, repointing of the interior basin and exterior wall, the Town also made repairs to the low level outlet and controls within the gatehouse itself."

Brookline is on track to reach "substantial completion" in late spring 2020, she said.

Who's paying?

Brookline got two state grants and a Massachusetts Preservation Project fund to help with the $3.1 million project.

Not just Brookline

More than 1,500 dams have been deemed problematic across the country, according to new data amassed during a two-year investigation by The Associated Press. Aging dams were a common problem nationwide, the AP found.

On average, the nation’s dams are more than 50 years old. In some cases, they weren't designed to handle the amount of water that could result from the increasingly intense rainstorms of a changing climate. NASA has said that rising temperatures will "intensify the Earth’s water cycle" and increase evaporation, bringing more storms and more rain to many areas, as well as an increased risk of flooding.

Despite the risks and need for repairs, little information has been publicly available about dam conditions, the AP found. Since 2002, the U.S. Army Corps of Engineers has redacted inspectors' condition assessments from its National Inventory of Dams, citing security concerns. Only the hazard rating of some dams are publicly available, which determine the likelihood of human death or economic and property loss in the event of a catastrophic failure.

The AP analysis was based on data obtained through dozens of state open-records requests, which allowed it to create a dataset containing both hazard levels and condition ratings for dams across 45 states and Puerto Rico.

Inspection reports also revealed a litany of problems. Some dams leaked, indicating internal failure. Others showed erosion, potentially destabilizing extensive tree growth or even holes from burrowing animals. In some cases, spillways were flagged because they aren't big enough to handle increased rainfall.

Patch reporter Jenna Fisher can be reached at Jenna.Fisher@patch.com or by calling 617-942-0474. Follow her on Twitter and Instagram (@ReporterJenna).