Low Impact Development

Low Impact Development

Introduction to Low Impact Development from SEMCOG’s LID Manual

Low Impact Development (LID) uses the basic principal of managing rainfall where it lands and using design techniques to infiltrate, filter, store, evaporate, and detain runoff close to its source. LID practices treat stormwater as a resource rather than a waste by preserving and recreating natural landscape features and minimizing impervious surface area to create functional and appealing site draining.  

Like LID, Green Infrastructure (GI) is a range of practices designed to store, infiltrate, or evaporate stormwater using vegetation, soils, and other elements and practices. Many LID and GI practices overlap and terms of often used interchangeably. Practices include bioretention, rain gardens, green roofs, bioswales, infiltration trenches, pervious pavements, subsurface infiltration beds, and water harvesting or reuse techniques such as rain barrels and cisterns.

Low Impact Development and Green Infrastructure practices manage water in a way that reduces the impact of built areas and promotes the natural movement of water within an ecosystem or watershed. At the site and regional scale, these practices aim to preserve, restore, and create green space using soils, vegetation, and rainwater harvesting techniques that mimic natural processes.  

Stormwater runoff is a major cause of water pollution in our lakes and rivers.  When rain lands on hard surfaces such as roofs and streets it cannot soak into the ground and is often directed into stormwater drains. Stormwater runoff carries pollution, trash, bacteria, and heavy metals from the urban environment and does not get cleaned before being directed into our surface waters.

Water quality is important to all of us. Protecting our lakes, rivers, and streams is critical to preserving the natural character of our rural areas, and maintaining a high quality of life in our villages and cities.