Multiple factors are involved in determining water quality, which the US Geological Survey suggests thinking of as the suitability of water for a particular use- this includes source water for drinking water. According to the US Environmental Protection Agency, the leading remaining cause of water quality problems is non-point source pollution. Many factors contribute to non-point source pollution, but broadly speaking it is made up of surface runoff from our roads, lawns, and other surfaces- including any pollutants that runoff picks up along the way, such as oil, chemicals, fertilizers, and pesticides. These pollutants are then carried into bodies of waters such as a river.
The rapid development of formerly undeveloped tracts of land exacerbates non-point source pollution, making the land unable to trap and filter pollutants before they reach waterways. By contrast, preserving the undeveloped land along our rivers and streams allows natural areas to protect water quality by processing nutrients and filtering contaminants from surface runoff. Wetlands and forested land, if left undeveloped, can help slow and filter water before it gets to lakes, rivers, and aquifers, keeping these drinking water sources cleaner and making treatment cheaper. Preserving water quality is important not only to protect our drinking water, but also because water quality determines if water is safe for swimming and fishing. It is also critical to the ecological health of the aquatic communities impacted by pollution, including plants and wildlife.
Sources & Further Reading
- What is Nonpoint Source Pollution?
- US EPA, National Water Quality Inventories
US EPA, National Water Quality Inventory: 2004, Report to Congress (United States Environmental Protection Agency, 1998), EPA841-R-08-001.
US EPA, National Water Quality Inventory: 1998, Report to Congress (United States Environmental Protection Agency, 1998), EPA841-R-00-001.
- Stream Corridor Restoration: Principles, Practices and Processes (Federal Interagency Stream Restoration Working Group, FISRWG, 1998)