Low Impact Development (LID)
Suburban Case Study

The Acton Discovery Museums installed an outdoor LID demonstration site at the Science Museum building to showcase LID technologies while increasing the amount of groundwater in the watershed through stormwater recharge. The Museum is an ideal location for homeowners, builders, municipal officials, school groups, and visitors to see Low Impact Development in action and learn more about water quality issues, water recharge efforts, and water conservation strategies.

The Assabet is unusual in that most, sometimes 80% or more, of its dry season flow comes from eight wastewater treatment plants along the river and its tributaries. Groundwater water withdrawals used for drinking, irrigation, and industrial uses are steadily increasing throughout the watershed. The river has been experiencing significant aquatic weed and algae problems and reduced base flows especially during dry summer months.

Photo provided by Acton Discovery Museums

Using rainwater to water adjacent gardens

 A Stormwater Recharge Project:

The Discovery Science Museum's LID demonstration site incorporates many LID technologies including rain barrels, rain gardens, pervious paving, and gravelpave and grasspave systems. These technologies increase groundwater recharge by reducing stormwater run-off and pollution by removing particulates and contaminants from rainwater. Also slower infiltration through the soil provides cleaner high-quality water to the underlying aquifers and groundwater reservoirs of the Assabet River watershed.

Since impervious surfaces can average 14% of the surface area in built environments including driveways, sidewalks, patios, pools, roadways, and building rooftops, replacing these surfaces with pervious ones helps alleviate some of the detrimental effects of typical urban and suburban development patterns and sprawl. In natural rivers and streams in New England, groundwater provides the water quantity (flow) for rivers, called base flow, and is thus critical during drier summer and fall seasons to ensure that there is adequate habitat and good environmental conditions are preserved for wildlife, recreational uses, and the aesthetic quality of river bodies.

As a result of the visible interest and fascination with the LID demonstration site, Museum officials developed a companion exhibit, "Watersheds, Watercycles, and You", funded by a grant from the Massachusetts Environmental Trust, that provides information on the relevance of the watercycle to human activities and includes handouts, displays, and programming events.

Low Impact Development Technologies In Detail:

Photo provided by Acton Discovery Museums

Kids looking at the amount of rain being caught in the rain barrel, rain gauge, and watering can; water is filtering though Grasspave and pervious pavers in the foreground,

The outside LID demonstration exhibit includes rain barrels, a rain garden, porous paving systems, and pervious stone paving. Together these techniques demonstrate environmentally sensitive design, utilize natural landscape features that recharge water back into the ground, and reduce the amount of impervious surfaces.

Rain barrels are connected to the roof drainage infrastructure of the Science Museum building, thus capturing rainwater from the roof and storing it to use for watering adjacent gardens, planters, and the Grasspave system. These rain barrels are particularly useful during periods of low rainfall and summer water bans.

The Rain Garden is grown in an area excavated slightly below grade and planted with native species of plants. It is an attractive natural area that captures rainfall and runoff from surrounding areas and holds water while allowing it to seep slowly into the ground. The rain garden is further sustained by water from the rain barrels.

Photo provided by Grasspave

Cutaway of Grasspave structure.

Grasspave is state-of-the-art landscaping technology which is a plastic subsurface reinforcement structure that provides load-bearing strength while protecting grass root systems planted within it from compaction. At the Discovery Museums it is used in areas bordering the rain garden, thus increasing infiltration of rainfall while reducing pollutants and fine particulates that otherwise would run off into nearby storm drains and streams. Grasspave's high compressive strength also makes it ideal for heavy use areas such as parking lots and along public areas.

Gravelpave is a porous paving system that uses a load bearing structure with open cups that contain and keep gravel in place. It is used in the Museum's picnic area and is appropriate for heavy traffic areas. Gravelpave creates a porous surface so rainfall can filter into the ground and recharge groundwater. More information on these pavers can be found at: http://www.invisiblestructures.com/

Photo provided by Acton Discovery Museums

The low maintenance job of raking the Gravelpave system in the picnic area; easy upkeep, pervious pavers are in the foreground.

Pervious stone paving is a permeable concrete paver that has funnel-shaped openings that are filled with coarse gravel. The specific product used in the LID demonstration site is Uni Eco-Stone. This paving is being used on the Museum walkways and entranceway.

LID Project Partnership:

The Discovery Museums' LID demonstration project was generously funded by a $56,570 grant for design and construction from Intel, a local company based in Hudson. The $1.5 million Intel Fund provides direct support to projects which will recharge stormwater in the Assabet River watershed in order to increase the base flow of the river. Additional project partners were the Acton Citizens for Environmental Safety (ACES) and the Organization for the Assabet River (OAR). Design and construction were completed by GeoSyntec Consultants, Inc. of Acton.