Low Impact Development

Schoharie Watershed Program

A program of Greene County Soil and Water Conservation District

Please use the links provided to access information on the SWP, its projects, and watershed issues

Schoharie Watershed Program

PO Box 996, 6049 Main Street

Tannersville, NY 12485

Phone 518-589-6871

Fax 518-589-6874

GCSWCD Main Office

907 County Office Building

Cairo, NY 12413

Phone 518.622.3620

Fax 518.622.0344

GCSWCD Home Page

What is Low Impact Development?

Low Impact Development (LID) is an ecologically friendly approach to site development and stormwater management that aims to mitigate development impacts to land, water, and air. The LID approach emphasizes the integration of site design and planning techniques that conserve natural systems and hydrologic functions on a site. The practice has been successfully integrated into many municipal development codes and storm water management ordinances throughout the United States. Specifically, LID aims to:

· Preserve open space and minimize land disturbance

· Protect natural systems and processes (drainage ways, vegetation, soils, sensitive areas)

· Reexamine the use and sizing of traditional site infrastructure (lots, streets, curbs, gutters, sidewalks) and customize site design to each site

· Incorporate natural site elements (wetlands,

· stream corridors, mature forests) as design elements

· Decentralize and micromanage stormwater at its source.

LID Benefits

In addition to LID just making good sense, low impact development techniques can offer many benefits to a variety of stakeholders.

Municipalities:

· Protect regional flora and fauna

· Balance growth needs with environmental protection

· Reduce municipal infrastructure and utility maintenance costs (streets, curbs, gutters, sidewalks, storm sewer)

· Increase collaborative public/private partnerships

Developers:

· Reduce land clearing and grading costs

· Potentially reduce infrastructure costs (streets, curbs, gutters, sidewalks)

· Reduce storm water management costs

· Potentially reduce impact fees and increase lot yields

· Increase lot and community marketability

Environment:

· Preserve integrity of ecological and biological systems

· Protect site and regional water quality by reducing sediment, nutrient, and toxic loads to water bodies

· Reduce impacts to local terrestrial and aquatic plants and animals

· Preserve trees and natural vegetation

Stormwater wetland at the Sugar Maples Stormwater Retrofit Project

Structural LID Practices

Stormwater Wetlands

Stormwater wetlands can be used to treat large areas and are often selected as a stormwater management practice because of their ability to remove excess nutrients and suspended solids from stormwater runoff. Stormwater wetlands provide similar habitat to natural wetlands. Wetlands are home to a variety insects and amphibians, many of which feed on mosquitoes and mosquito larvae.

Raingardens

Raingardens are an ideal method of treating stormwater on-site in urbanized settings. Raingardens are depressions in the ground that consist of loose, deep soils and are planted with colorful native vegetation.

Permeable Pavement

Unlike traditional pavement, permeable pavement allows rainwater to move vertically, down through the parking surface and into the underlying soils.

Bioswales

Bioswales are landscape elements designed to remove pollution from surface runoff water. The bioswale filters sheet flow from the porous pavement system during excessive rainfall events and also provide a snow storage area with treatment capacity.

Rain Barrels

Rain barrels are water tanks which are used to collect and store rain water runoff, typically from rooftops via rain gutters. Storing this water reduces stormwater runoff, and also provides a free source of water that can be used for watering gardens, washing cars, flushing toilets, and doing laundry.

Water Quality Issues Associated with Stormwater Runoff

Nonpoint Source Pollution

Nonpoint source (NPS) pollution comes from many diffuse sources. NPS pollution is caused by rainfall or snowmelt moving over and through the ground. As the runoff moves, it picks up and carries away natural and human-made pollutants.

Total Suspended Solids

The amount of particles that suspend in a sample of water is called total suspended solids (TSS). The greater the TSS in the water, the higher its turbidity and the lower its transparency (clarity).

Why Impervious Cover Affects Water Quality

Impervious surfaces like asphalt, cement and roofing prevent infiltration of rainfall into the soil, disrupting the water cycle and affecting both the quantity and quality of our water resources.