Stormwater is a topic that can make community leaders uneasy with worries about pollution, flooding, aging infrastructure, erosion and regulations. But, what if communities thought about stormwater in a positive way, such as recharge for groundwater supplies, irrigation for plants, and adequate water for stream critters?

Often in the past, developers and engineers viewed stormwater as something that should be collected and removed from a site as quickly as possible, usually through drains, pipes and other municipal infrastructure. More contemporary views consider stormwater an asset that sustains green plants and replenishes groundwater systems, important as drinking water sources and for adequate water flow in streams.

At its best, stormwater management in the built environment would create as many opportunities as possible for water to infiltrate into the ground, be filtered through the soil and used by plants not far from where rain and snow fall. Low impact development (LID) attempts to do just that and allows the water cycle to function as similarly as possible in the built environment as it would if the site were in a natural state. Under such a circumstance, there would be no need to collect and convey large amounts of water off the site.

If you are interested in New Hampshire’s water resources, community resiliency and innovative building techniques, save the date of June 12, for New Hampshire’s stormwater and low impact development (LID) conference. It will take place at the Great Bay Gallery in Somersworth and is designed to address the information needs of community board and staff members. In the fall of 2008 a similar conference will take place for all the northern New England states for development professionals including engineers, architects, business owners and landscapers.

LID is a relatively new way to think about stormwater management. LID is typically carried out in two major ways, better site design and structural LID techniques. Better site design is achieved when engineers and developers preparing to build do everything they can to protect existing natural areas, wetlands and plants, minimize hard surfaces such as pavement, and avoid excessive clearing and grading. Structural LID techniques are deliberately designed and constructed landscape features or devices that allow water to infiltrate soil, be filtered by soil and plants, and be stored and treated on the site. Examples of structural LID techniques include rain gardens, gravel wetlands, and vegetated swales.

The Stormwater Center at UNH has been testing the performance of various LID techniques to see if, and how well, they work. After several years of evaluation and monitoring, the results are exciting and overall, positive. So why aren’t more communities using LID? There are a number of reasons ranging from fear of trying something new to regulations that unintentionally discourage or prohibit it.

UNH Cooperative Extension is working with the U.S. Environmental Protection Agency, the Universities of Maine and Vermont Cooperative Extensions to design a conference on low impact development for local board members and municipal staff members in each of the northern New England states. While each state is working from a similar set of objectives, each state is incorporating its own speakers, topics and case studies. UNH Cooperative Extension is planning the New Hampshire conference with help from New Hampshire’s Dept. of Environmental Services and Coastal Program, NH Estuaries Project, the Great Bay National Estuarine Research Reserve, Strafford Regional Planning Commission, Rockingham Planning Commission, Hodgson Brook Restoration Project, towns of Durham, Dover and Exeter and, of course, the UNH Stormwater Center.

For more information on either conference, contact Extension Specialist Julia Peterson at 749-1565 or by email at julia.peterson@unh.edu