'Unsafe' Dam A Threat To Marlborough, Sudbury: Documents

MARLBOROUGH, MA — An Associated Press investigation has revealed that at least 39 dams in Massachusetts are in poor or unsafe condition, including the dam at Hager Pond in Marlborough. The dam was recently deemed "unsafe" during an inspection, and it's unclear who is responsible for overseeing the structure, according to officials.

The Hager Pond Dam is on the northeast side of Hager Pond, just a few yards from Route 20 and Wayside Inn Road. A spillway at the dam is crumbling and blocked by debris, an inspection found, and trees growing atop the embankments might have weakened the structure.

A failure of the Hager Pond dam could endanger several homes nearby, destroy the Hager Road bridge, and could even endanger the Wayside Inn, which is downstream from the dam after the Grist Millpond, according to documents. But areas around Wayside Inn Road, Pride’s Crossing Road, Dutton Road, and Hager Road also could be affected.

Patch followed up with local and state officials about the Hager Pond dam and found that ownership of the dam is unclear, leaving questions about who is supposed to maintain and monitor the structure.

Inspection finds dam 'unsafe'

In November 2018, a team from the firm GZA GeoEnvironmental inspected the dam on behalf of the state Department of Conservation and Recreation.

"The noted deficiencies at Hager Pond Dam during this inspection include dense vegetation and trees on the embankment and severe distress at the spillway structure, including outflow bypassing the spillway structure," the report reads.

The spillway is in the woods on the northeast side of Hager Pond, just a few yards from the edge of Route 20. On a recent day, the boxy concrete spillway was clogged with debris like sticks, rocks, leaves, and at least one piece of lumber.

Notably, water was gushing over both sides of the spillway. In the November 2018 GZA report, water had only over-topped one side of the dam. Water flowing over the sides of the dam can erode and weaken the embankments that flank each side of the spillway, the GZA report warns.

There are a few homes nearby the spillway. The closest is under construction and uninhabited. One homeowner, whose property borders the southeast embankment, said that she had lived in the area for 25 years and had never heard anything about dam one way or another.

Doug Stanczak, who has lived a few houses up Hager Road from the dam since 2005, also said he hasn't heard anything about the dam. The school bus stop is adjacent to the dam, and he has noticed water flowing over all sides of the structure while standing there with his kids.

"It didn't look like it was damming anything," Stanczak said.

The GZA report also says that the "unsafe" condition of the dam is subject to change.

"It would be incorrect to assume that the present condition of the dam will continue to represent the condition of the dam at some point in the future," the GZA report said. "Only through continued inspection and care can there be any chance that unsafe conditions be detected."

Ownership in question

Next to the dam's structural problems, it's unclear who owns the dam.

Both the emergency action plan (EAP) and inspection report list the owner of the dam as "unknown." And that might mean no one is either looking for dam problems or doing maintenance.

The EAP lists Marlborough Fire Chief Kevin Breen and DCR Dam Safety Chief William Salomaa as the two main contacts in case of a dam emergency. But when contacted about the EAP, Breen said he hadn't seen it — although he is familiar with EAP plans for other dams in Marlborough. The EAP also outlines that Marlborough's Department of Public Works will repair the dam in case of an emergency. Commissioner of Public Works John Ghiloni did not immediately respond to requests for comment about the dam.

In February, Marlborough highlighted the Hager Pond Dam as a "high hazard" during a community resilience workshop — but state officials had warned about the dam as long ago as 2005, according to news reports. A "high-hazard" dam is one that, were it to fail, could result in the loss of at least one life.

As of Nov. 14, the state still did not know who owns the dam. But the DCR Office of Dam Safety has had an EAP in place for Hager Pond since 2010. Marlborough acknowledged receipt of the EAP in 2010, but Breen only became chief in 2015.

"[The state] remains committed to the safety of residents, infrastructure, businesses, water supply, and the environment, and since 2006 the state has invested more than $58 million helping private landowners, communities, stakeholders, and state agencies with the finalization of designs, and reconstruction or removal of dams. Through the Department of Conservation and Recreation’s Office of Dam Safety, the state will continue its efforts to improve records of dams, closely monitor dam infrastructure throughout Massachusetts, and assist dam owners to ensure statutory and regulatory obligations are being met," DCR spokesman Troy Wall said in a statement.

The EAP contains two scenarios for dam failure: a "sunny-day" scenario where the dam fails during normal water levels; and a worse scenario involving a failure when flood levels are at half the maximum possible.

In the worse scenario — a dam failure when water levels are one foot higher than normal — it would take about 36 minutes for water to reach the end of its predicted flow, about 2.6 miles down Hop Brook at the rail bridge near the Hopbrook Marsh Conservation Land.

The EAP notes that wide swaths of flood plain and riparian land would absorb most of the flow. But the Hager Street Bridge and Carding Mill Pond and Grist Mill Pond dams would be in danger. The height of the water would be about 6 feet at the spillway, but farther downstream would be about 1 foot higher than normal, the action plan says.

Part of larger problem

Aging dams were a common theme nationwide, the AP found in analysis of dam safety reports.

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. Rising temperatures will "intensify the Earth’s water cycle" and increase evaporation, according to NASA. That increased evaporation will bring 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 created an exclusive dataset that fills in those information gaps for a subset of dams across the country. It found at least 1,543 "high-hazard" dams that are in poor or unsatisfactory condition.

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. Five states – Alabama, Illinois, Maryland, New Jersey and Texas – did not fully comply with the records request. Iowa provided all requested documents but had no dams listed as both high hazard and in poor or unsatisfactory condition.

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.

The AP data also showed yearly budget and staffing levels for dam safety offices in each state. Massachusetts in Fiscal Year 2019 budgeted nearly $1.2 million to dam safety and had a staffing level of 7.1. The decimal indicates state officials fund part-time positions or split workers' time between dam safety and other programs.

Georgia had the most high-hazard dams in poor or unsatisfactory condition at 198. North Carolina was second with 168, followed by Pennsylvania at 145, Mississippi with 132, Ohio with 124 and South Carolina with 109.

Massachusetts has the 12th-highest number in the country. While the dams were spread out across the state, some were located around Boston, including Brookline, Dedham, and Braintree. The Brookline Reservoir Dam dates to 1848 and the Great Pond Dam in Braintree dates to 1940. In another case, the Chartley Pond Dam, also in poor condition and a risk to human life, is more than 300 years old.