SHELBURNE FALLS — Although the flashboards at the dam near the Glacial Potholes are designed to break in the wake of heavy flows, Great River Hydro has found itself coping with unusually frequent overflows during this summer’s rainy weather.

According to Matthew Cole, public information officer with Great River Hydro, the hydropower company repaired the dam’s flashboards last week. While seeing broken pieces may draw concern from passersby, Cole assures the public that the mechanism is designed to break as a safeguard from the rushing river.

“The boards are designed to fail at such time when approximately 2 feet of water overtops them,” Cole wrote in an email. Having the flashboards break, he said, can reduce upstream flooding and protect the dam.

This pin and flashboard system has been in place since the dam first began operating more than 100 years ago, according to Cole. He explained this is a common design and there are many dams with similar features to allow water to pass during high flows.

“It is not unique,” he wrote.

However, Cole confirmed that many areas where Great River Hydro operates dams appear to have higher accumulated rainfall totals this summer than in the past, and subsequently, the water is reaching this 2-foot threshold more frequently.

Similarly, during Tropical Storm Irene in 2011, the dam’s pre-existing hydraulic flashboard system was damaged. Since then, Great River Hydro has been working with engineers and the Federal Energy Regulatory Commission (FERC) to restore the system and attempt to make it more resilient than it was before the damage occurred.

Another concern for Great River Hydro is the large amount of debris in the Deerfield River after a storm. This debris can block the canal and powerhouse intake structures. Cole wrote the company has maintenance procedures in place to address these issues.

Some residents have expressed concern with the safety of swimmers and boaters near the dam in the wake of these broken boards. Cole explained there is already no swimming allowed in the area around the dam, which is conveyed to the public through warning signs.

“There is a significant amount of spill already occurring before the boards begin to fail,” Cole wrote, “and the amount of flow would not be conducive to swimming and wading below the dam.”

Bella Levavi can be reached at 413-930-4579 or blevavi@recorder.com.