Activity 3.3 addresses NPDES permitting requirements for point source discharges of wastewater. This discussion will address NPDES permitting requirements for nonpoint sources. Nonpoint source pollution is defined by the EPA (Links to an external site.)as “pollution that is not released through pipes but rather originates from multiple sources over a relatively large area.” It’s more easily defined as “Pollution that occurs when rainfall, snowmelt, or irrigation runs over land or through the ground, picks up pollutants, and deposits them into rivers, lakes, and coastal waters or introduces them into groundwater” (2018, para 2).
Stormwater discharge from construction sites is particularly of concern because ground cover, including grass and other plants, have been removed, and in most cases, the surface has been leveled so that channels for the runoff have been eliminated. Soil exposed by construction activities is particularly vulnerable to erosion, and when this soil runs to a stream or creek, the excess sediment can impede navigation and cloud the water, affecting fish and reducing the amount of sunlight that reaches aquatic plants.
In addition, as we build more facilities and homes, we increase the amount of impervious surfaces and reduce the amount of surfaces where stormwater can seep back into the ground, limiting groundwater recharging. ( Large areas of impervious surfaces can also increase the chance of localized flooding if surface water collection is not adequate. Many companies and municipalities are turning to Low Impact Development (LID) practices, also called Green Infrastructure, to manage stormwater and allow it to “promote the natural movement of water within an ecosystem or watershed.” For more information, read Urban Runoff: Low Impact Development (Links to an external site.) and Ground Water & Stormwater Management. (Links to an external site.)
Find an example or a case study of a facility or development that has successfully implemented a Low Impact Development or Green Infrastructure project. Summarize (do not copy) some key aspects of the project. How can your employer or a selected industry incorporate some of these principles? Is it cost effective? Should cost play a role?