Stormwater Runoff from Commercial Areas
Stormwater runoff is generated when precipitation from rain and snowmelt events flows over land or impervious surfaces and does not percolate into the ground. Imervious surfaces include areas such as:
- Paved streets
- Parking lots
- Building rooftops
As the runoff flows over the land or impervious surfaces, it accumulates potential pollution from:
- debris and litter
- chemicals
- sediment and nutrients
- bacteria and other pollutants
These can adversely affect water quality when the runoff is not treated before it is discharged to waterways.
What can municipal officials do?
Low Impact Development (LID) is a set of best management practices that works with nature to manage stormwater as close to its source as possible. This approach to land development (or re-development) employs principles such as: 
- minimizing imperviousness of areas
- preserving natural landscape features
- creating functional landscape features
These achieve appealing site drainage, transforming stormwater from a waste product into a resource or component of the development. Examples of various practices include:
- rain gardens and other functional landscaping
- vegetated rooftops
- rain barrels for collecting water for later use on plantings
- bioretention facilities
- permeable pavements
The primary principle of LID is very simple: soak the water back into the ground BEFORE is gets contaminated. Traditionally stormwater management techniques seek to dispose of stormwater.
The beauty of LID approaches:
- adaptability to a range of land uses from high density ultra-urban settings to low density rural development
- very often costing less than conventional development approaches