Stormwater Management & Best Management Practices

Specific Types of Best Management Practices

Non-Structural BMPs

The most effective way to manage stormwater begins with the prevention of problems.

Non-structural BMPs include design approaches and practices that are used for their ability to prevent the occurrence of stormwater runoff. Utilizing non-structural BMPs during site development is much more efficient and cost-effective than attempting to correct problems after development has occurred.

Read below to learn about specific types of non-structural BMPs.  Additional information can be found at:

Specific Types of Non-Structural BMPs

Riparian Corridor
Riparian corridors protect water quality and provide
many other environmental benefits.

Riparian Corridors/Buffers
A riparian corridor includes body of water (stream, river, pond or lake) its lower and upper banks and the vegetation that stabilizes the area of land adjacent to the body of water. This area of land adjacent to the body of water can also be referred to as a “riparian buffer”. This corridor or buffer is important because natural trees and vegetation can filter out air and water pollution, roots from tree and other vegetation can hold the soil in place providing protection from significant erosion and sedimentation, provide cover and shade, provide food and habitat for fish and wildlife, and can provide flood water retention.

Preservation and restoration of riparian corridor/buffers has been identified as one of the most important ways to protect and improve water quality by government and state agencies.

For information on riparian buffers/corridors, please see the following links:

Protect Sensitive and Special Value Features
Special Value Features are those that provide exceptional value stormwater benefits. Examples include riparian areas, wetlands, hydric soils, and floodplains. Sensitive Features are those that are exceptionally vulnerable to stormwater damage. Examples include steep slopes and neighboring properties. Damage to both special value and sensitive features can exacerbate stormwater volume, rate, and quality problems. When developing a site, special attention should be paid to these areas. Learn more below.

Protect / Utilize Natural Flow Pathways in Overall Stormwater Planning and Design
Sites usually have areas where stormwater is being stored and/or conveyed prior to development. These features should be identified and preserved during planning and construction in order to minimize the impacts of stormwater.  The preservation of such features can reduce the need for structural BMPs.  Learn more below.

Cluster Uses at Each Site and Build on Smallest Area Possible
Through clustering uses at each site and building on the smallest area possible, additional runoff that is generated through the development process is minimized.  Additional benefits of this design approach include the preservation of open space, the minimization of impervious area, and many others.  Practical examples of this non-structural BMP include reducing lot size and building vertically.  Learn more below.

Use Smart Growth Practices
Smart Growth practices are typically used at the community, municipal, or multi-municipal level.  This planning technique guides growth towards parcels that are most desirable for this use.  The PA Stormwater BMP Manual describes this particular BMP as “Super Clustering.”  Smart Growth employs similar methods on a macro scale as clustering does on a micro (site) scale.  Tools used in Smart Growth include urban growth boundaries, agricultural zoning, transfer of development rights, donation of conservation easement by owners, and many more.  Learn more below.

Minimize Total Disturbed Area--Grading
This design approach works with the existing site topography instead of against it.  By reducing the need for site grading, soil disturbance, and removal of vegetation, this planning and development approach aims to prevent the generation of stormwater.  Additional benefits of Minimizing Total Disturbed Areas & Grading include reduction of areas that need to be landscaped and maintained.  Learn more below.

Minimize Soil Compaction
Minimizing soil compaction and maintaining top soil quality during construction provides numerous stormwater benefits.  Stormwater benefits of this practice include: minimizing runoff and erosion, maximizing water retention capacity, filtering of stormwater, and reducing resources needed to maintain landscaping.  Learn more below.

Re-Vegetate and Re-Forest Disturbed Areas
Disturbed areas should be re-vegetated with native plants, grasses, shrubs, and trees.  Since these species are adapted to local climate and conditions, they require less fertilizers and pesticides and have better chances of surviving.  Stormwater benefits of established native plantings include runoff volume and rate reduction as well as water quality improvements.  Learn more below. 

Reduce Street and Parking Imperviousness
The benefits of reducing impervious areas for streets and parking through innovative planning are numerous.  Benefits include: increased infiltration, decreased stormwater volume, pollutant load reduction, and preservation of natural habitats.  Learn more below.

Rooftop Disconnection
Rooftop disconnection is also known as downspout disconnection.  Disconnecting rooftop leaders from the storm sewer system and re-directing towards vegetated areas is an effective way to manage stormwater volume.  This BMP can be more effective when the flow is directed towards a structural BMP such as a rain garden.  Learn more below.

Disconnection from Storm Sewers
Disconnecting stormwater generated from impervious areas such as roads and driveways from storm sewers and directing towards structural BMPs such as bioinfiltration areas is effective in many ways.  Managing the flow near the source instead of sending downstream via traditional piping allows for increased infiltration and evapotranspiration, increased filtration, and decreased runoff volume. Learn more below.

Streetsweeping is a form of source control that is key to ensuring the function of stormwater facilities and keeps local waterways free of debris and other pollutants.  In order for streetsweeping to be effective, the equipment used should have a vacuum filter.  Learn more below.

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