At the last Town Council Meeting on Dec. 22, Edward Tanner, Principal Planner, presented a conceptual stormwater management and landscape plan for the Town Common to the Council. He was accompanied by Arnold Robinson, Regional Director of Planning for the engineering firm Fuss & O’Neill, which prepared the plan.

According to Tanner, the Common has been a longtime area of concern for his department. Stormwater puddling in certain areas and running off in others has caused erosion issues as well as contributed to water quality problems when that stormwater floods into the storm drains and eventually reaches the Harbor.

“That water quality issue is at the heart of what we are looking at — we are looking at creative solutions and to show people what can be done,” said Tanner.

To that end, Tanner, along with Community Development Director Diane Williamson, obtained a technical assistance grant from the Southeast New England Program (SNEP) Network — a grant, Tanner pointed out to the pleasure of the Council, that does not have a matching requirement.

The plan created by Fuss & O’Neill, and funded by that grant, includes recommendations for stormwater management and landscape improvements on the Common, with the goal of improving water quality while minimizing the the quantity of water reaching the Harbor.

Stormwater a growing concern
One of the biggest areas of concern is the playground, which remains marshy and muddy after a typical rainstorm. As for the runoff issue, Robinson gave hard figures, in gallons of water, for each type of rainstorm. He noted that a typical heavy rainstorm, of which we have about 30 per year, results in runoff of about 30,000 gallons of untreated water to the Harbor. A one-year storm will add 185,000 gallons into the Harbor.

“We had four of those last year,” said Robinson of the once-a-year predicted rain event.

What’s more, of the “10 year” storms — storms that are of a severity that is only anticipated once in every 10 years — Bristol had two in the last year. A so-called 10 year storm results in 500,000 gallons of untreated runoff water in the Harbor.

Robinson also noted the importance of the Common as a historical centerpiece in town and underscored that any work would be very low impact and not change the appearance of the Common, but would nonetheless result in a 78-92 percent reduction in runoff, were it to be all completed.

Plan outlines five priorities
Robinson highlighted five key interventions that his firm identified: bioretention systems (which consist of planted vegetation which provides uptake of pollutants and runoff) at two sites — by the parking lot along State Street and along the south side of the Common between the basketball court and Church Street; a stone “diaphragm” on the slope between the tennis courts and Wood Street; cutting down on the area of impermeable pavement around the Byfield School building; and a robust program of tree maintenance and replacement.

According to Robinson, the plan can easily be enacted in phases, depending on what sort of grant opportunities the Town is able to take. He recommends addressing the areas closest to the muddy playground first.

“That’s where you will get the most bang for your buck,” he said.

The parking lot adjacent to State Street, for which Tanner has already identified a granting opportunity under the federal Clean Water Act, is another likely starting point.

The Council received and filed the plan as no action was needed on their part at the time. The presentation to the public was a requirement of the SNEP grant and the plan will be used to guide projects and support grant opportunities in the future.

To view the plan it its entirety, click here and then click on Town Common Master Plan.