Low Impact Development Overview
The term low impact development (LID) refers to systems and practices that use or mimic natural processes that result in the infiltration, evapotranspiration or use of stormwater in order to protect water quality and associated aquatic habitat.
EPA currently uses the term green infrastructure to refer to the management of wet weather flows using these processes, and to refer to the patchwork of natural areas that provide habitat, flood protection, cleaner air and cleaner water.
At both the site and regional scale, LID/GI practices aim to preserve, restore and create green space using soils, vegetation, and rainwater harvest techniques. LID is an approach to land development (or re-development) that works with nature to manage stormwater as close to its source as possible. LID employs principles such as preserving and recreating natural landscape features, minimizing effective imperviousness to create functional and appealing site drainage that treat stormwater as a resource rather than a waste product.
There are many practices that have been used to adhere to these principles such as bioretention facilities, rain gardens, vegetated rooftops, rain barrels and permeable pavements. By implementing LID principles and practices, water can be managed in a way that reduces the impact of built areas and promotes the natural movement of water within an ecosystem or watershed. Applied on a broad scale, LID can maintain or restore a watershed’s hydrologic and ecological functions.
Low Impact Development (LID) is a stormwater and land-use management strategy that tries to mimic natural hydrologic conditions by emphasizing the following techniques:
- Conservation
- Use of on-site natural features
- Site planning
- Distributed stormwater best management practices (BMPs) integrated into a project design
Nonpoint Source: Urban Areas
Urbanization increases the variety and amount of pollutants carried into our nation’s waters. In urban and suburban areas, much of the land surface is covered by buildings, pavement and compacted landscapes. These surfaces do not allow rain and snow melt to soak into the ground which greatly increases the volume and velocity of stormwater runoff. In addition to these habitat-destroying impacts, pollutants from urban runoff include:
- Sediment
- Oil, grease and toxic chemicals from motor vehicles
- Pesticides and nutrients from lawns and gardens
- Viruses, bacteria and nutrients from pet waste and failing septic systems
- Road salts
- Heavy metals from roof shingles, motor vehicles and other sources
- Thermal pollution from impervious surfaces such as streets and rooftops
These pollutants can harm fish and wildlife populations, kill native vegetation, foul drinking water, and make recreational areas unsafe and unpleasant.
Urban Runoff: Model Ordinances to Prevent and Control Nonpoint Source Pollution
Many communities across the nation are facing challenges associated with natural resource degradation due to rapid growth and development. Local governments need to have legal authorities in place to shape development and to protect resources.
The ordinance types matters that are often forgotten in many local codes including aquatic buffers, erosion and sediment control, open space development, stormwater control operation and maintenance, illicit discharges and post construction controls.
- Aquatic Buffers
- Erosion & Sediment Control
- Open Space Development
- Stormwater Control Operation & Maintenance
- Illicit Discharges
- Post Construction Controls
- Source Water Protection
Fact Sheets and Technical Reports
Link to fact sheets and technical reports.
Also find fact sheets and technical reports both here and on EPA’s Green Infrastructure pages.
Barrier Buster Factsheet #1: How LID Can Protect Your Community’s Resources (PDF) (2 pp, 1 MB, March 2012, EPA 841-N-12-003A)
- Barrier Buster Fact Sheet #2: Terminology of Low Impact Development Distinguishing LID from other Techniques that Address Community Growth Issues (PDF)(2 pp, 601 K, March 2012, EPA 841-N-12-003B). Addresses LID’s place in the jumble of terms for managing the environmental impacts of growth that coexist today and describes and distinguishes these terms.
- Barrier Buster #3: Costs of Low Impact Development: LID Saves Money and Protects Your Community’s Resources (PDF)(2 pp, 2 MB, March 2012, EPA 841-N-12-003C). Challenges the perception that LID is too expensive.
- Barrier Buster #4: Aesthetics of Low Impact Development LID Technologies Can Benefit Your Community’s Visual Environment (PDF)(2 pp, 2 MB, March 2012, EPA 841-N-12-003D). Challenges the perception that LID is unattractive.
- Effectiveness of Low Impact Barrier Buster # 5: Development Proven LID Technologies Can Work for Your Community (PDF)(2 pp, 2 MB, March 2012, EPA 841-N-12-003E). Challenges the perception that LID doesn’t work.
- Barrier Buster #6: Maintenance of Low Impact Development Communities Are Easily Managing LID Practices (PDF)(2 pp, 2 MB, December 2012, EPA 841-N-12-003F). Challenges the perception that LID is too hard or costly to maintain.
- Barrier Buster #7: Encouraging Low Impact Development Incentives Can Encourage Adoption of LID Practices in Your Community (PDF)(2 pp, 504 K, December 2012, PA 841-N-12-003G). Highlights incentive strategies to catalyze LID.
- Barrier Buster #8: Soil Constraints and Low Impact Development Careful Planning Helps LID Work in Clay Soils (PDF)(2 pp, 2 MB, October 2014, 841-R-14-004A). Challenges the perception that LID can’t work in clay soils.
- Barrier Buster #9: Slopes and Low Impact Development Designing and Siting LID Practices on Slopes (PDF)(2 pp, 638 K, August 2015, EPA 841-R-14-004B). Challenges the perception that LID doesn’t work in areas with significant slopes.
- Barrier Buster #10: Large Volume Storms and Low Impact Development – Using LID Practices in Areas with Intense Rainfall Events (PDF)(4 pp, 3 MB, October 2017, EPA 841-F-16-009). Challenges the perception that LID doesn’t work in areas subject to large volume storms.
- Barrier Buster #11: Space Limitations and Low Impact Development – LID Practices are Well-Suited for Small Spaces (PDF)(3 pp, 4 MB, August 2018, 841-F-16-010). Challenges the perception that LID requires a lot of space.
Center for Watershed Protection
CWP’s resources include more than 250 Guidance manuals, articles and reports to assist with watershed and stormwater management needs.