BERLIN – Growth has outpaced Berlin’s stormwater systems, overloading insufficient-sized pipes, inadequate ponds, low ground and high water tables, the town learned Tuesday night from the Army Corps of Engineers (ACE) stormwater analysis.
The long anticipated, three years in the making, Berlin stormwater study results were finally presented to the Berlin Mayor and Council this week. The study, conducted by ACE, was concluded in August.
Seven high priority areas, were identified, Craig Thomas of ACE reported. In high priority areas, the entire system floods, primary roads are impassable, and homes and other buildings can flood.
“It was a three-year study, a very comprehensive, in-depth study,” Thomas said, calling the analysis of a planning level document the first step in improving Berlin’s flooding problems. “The primary goal was a comprehensive investigation to determine specific causes of flooding within the town corporate limits.”
The study began with stormwater system mapping, followed by modeling and problem identification, and ending with alternatives for improvements.
“There’s issues in the entire town,” Thomas said.
Both infrastructure improvements and stormwater best management practices (BMPs) can be employed to reduce flooding in Berlin, Thomas said, including infrastructure changes like the addition of new stormwater inlets and modified pipes to BMPs like rain barrels and new wetlands.
Overall, Thomas said, Berlin needs to reduce existing flows while being careful not to simply move the water elsewhere, minimize environmental, economic, infrastructure and social impacts and make sure measures taken are cost effective and directed at destructive flooding, not just nuisance flooding.
The high-priority areas need a range of improvements.
At Henry’s Mill and Henry’s Green developments, well known for stormwater problems, the pipes are too small, the groundwater is high, and the stormwater pond has too little capacity to handle run-off from both developments.
“All the ditches get filled with water and basically all your cul de sacs are under water,” Thomas said. “The water simply has nowhere else to go.”
The study engineers came up with cites 17 alternatives to improve flooding in those communities. Replacing open drainage ditches with curb and gutter inlet systems could be one solution, although it is the highest cost alternative for that site.
Thomas suggested a workshop to deal with the Henry’s Mill and Henry’s Green areas alone.
The Perdue feed plant area would benefit from a stormwater pond, the study concluded.
“There’s lower ground,” Thomas said. “There’s no stormwater inlet there to carry that water out.”
A different type of high water occurs at Bottle Branch near Gull Creek, where residents experience riverine flooding, which could affect five homes.
Protective measures can be taken at the homes themselves. Wet flood proofing involves relocating or removing utilities and affected items from basements before the lower level floods, while dry proofing involves keeping the water out altogether with a wall.
“The Corps actually has flood proofing experts that come out and look at homes,” Thomas said.
Medium priority areas include Main St. near the Berlin Library, West St. at Broad St., Routes 113 and 346, and Bottle Branch at Main St.
Homeowners can reduce some flooding on their property and improve local water quality by adding rain barrels and rain gardens and directing gutter spouts onto grass, Thomas said.
While the study did not focus on lessons for future development, Thomas said that the town could add a few general principles to the planning process.
“Always look at what you’re doing in downstream areas. Always look at your impact,” Thomas said. “Look at all your issues. Don’t just look at that box where that property is going to be.”
He added, “We don’t have any steadfast rules. We didn’t look at any future development scenarios or future development modeling in this report.”
Council Vice President Gee Williams said, “Newer developments are not going to fix the problems that are already there.”
Plans for new development should include how that construction would impact existing stormwater problems, said Councilman Dean Burrell.
“What we’ve been doing obviously hasn’t been enough so new standards have to be adopted,” Williams said.
The entire study will be available at the Berlin Library on DVD, while Worcester County Comprehensive Planning Director Sandy Coyman has offered to host the document on the county website for home viewing.
“I want to make sure if the people want [copies] then they don’t have to pay for a paper copy,” said Mayor Tom Cardinale.