First Unitarian Society Meeting House

Top Ten Measure 6: Water Cycle

This project achieved a significant environmental goal: The building footprint was doubled, yet stormwater runoff was virtually eliminated.

Prior to the addition, severe stormwater runoff caused localized flooding of neighboring properties. With the addition completed and landscaping established, virtually all stormwater is now retained on site. No runoff has crossed the property line onto adjacent property. Even during a major, 100-year storm event in 2010, only a nominal amount of stormwater entered the municipal system.

This improvement is due to an ensemble of cooperating measures. First, a vegetated roof absorbs substantial rainwater. Once the roof is saturated, runoff flows to a terrace, where it is directed into an underground infiltration chamber. Overflow is piped to one of two rain gardens. Stormwater falling onto impervious roofing is directed onto a pervious, landscaped courtyard to be absorbed. Overflow is piped to the second rain garden. Runoff generated by impervious parking surfaces is directed through a series of bioswales to promote infiltration.

Native and drought-tolerant flora were selected for all landscaping, including the green roof. No irrigation is provided or required.

Building water use has been reduced by 35% over comparable facilities. Strategies include dual-flush toilets, waterless urinals, and low-flow faucets.