Stormwater pollution is one of the most devastating events for local climates and ecosystems.
For this reason, the EPA–and state district offices in some cases–requires organizations that discharge stormwater into public waterways to acquire a National Pollutant Discharge Elimination System (NPDES) permit.
To qualify for this permit, dischargers must submit a stormwater pollution prevention plan (SWPPP) detailing preventative measures to curtail stormwater pollution, erosion of the surrounding environment, and other harmful environmental effects.
Since stormwater runoff is a natural occurrence of man-made activity, construction managers can’t avoid the responsibility of forgoing a SWPPP. Additionally, municipalities of a certain size must also develop their own stormwater management plan (SWMP) to comply with the Clean Water Act, which puts additional restrictions on active construction zones.
Creating a SWPPP can be complicated, but with the right knowledge and help it can be manageable. By identifying potential sources of pollution, construction managers and builders can construct a straightforward SWPPP that addresses local environmental concerns and ensures proper restoration of the surrounding disturbed land.
This article will discuss the importance of a SWPPP and the seven primary sources of pollution that all SWPPP consultants and managers should know when writing a SWPPP plan.
The Importance of a SWPPP
An SWPPP is a formal plan required to qualify for an NPDES permit. Since most construction zones are often forced to divert or dump stormwater in public waterways, they are required to implement controls that limit the velocity of stormwater runoff and the pollution of said runoff.
SWPPPs are designed to protect the local environment and provide temporary measures during construction to mitigate potential environmental catastrophes.
In addition, SWPPPs must provide protocols for workers’ safety and SWPPP inspection requirements.
Typically, a manager of a construction zone or a consultant will be responsible for developing a SWPPP. However, to construct an inclusive SWPPP proposal, it’s keen to understand and identify all possible sources of pollution that could come in contact with stormwater runoff.
7 Sources of Potential Stormwater Pollution
Understanding where stormwater pollution comes from will allow you to plan the right controls to manage it on a worksite.
1. Sediment and Suspended Sediment
Sediment is one of the most apparent causes of stormwater pollution. That’s why most BMPs inside a SWPPP are designed to maintain sediment control from debris, garbage, concrete, and plastics.
Sediment pollution occurs as a result of extensive erosion, which allows soil particles underneath the top layer to become exposed to the elements and mix with oncoming stormwater.
In addition, suspended sediment from more coarse materials, such as clay, sand, and silt can be a massive river and stream polluter.
Some popular controls designed to limit sediment and suspended sediment include rain gardens, silt fences, hydroseeding, crop cover, permeable pavements, and much more.
2. Chemicals and Pathogens
Chemicals, chlorides, and pathogens are probably the most dangerous and controversial sources of stormwater discharge.
Industrial solvents and chemical pesticides should be used cautiously and thoroughly discussed with an environmental consultant. Some effective control measures, such as buffer strips, allow pesticides to adhere to soil and separate from water.
Unfortunately, chemical runoff can be difficult to track and treat, making preventative maintenance key.
In addition, chlorides, such as chloride additives in concrete to common de-icing materials and pathogens from animal feces, sewage, and toilet rentals, are also massive sources of pollution if not properly controlled. You’ll need to ensure that a proper sewage disposal service can dispose of all sewage sources on your site and that barriers are put in place to stop the spread of chlorides.
Contact your local municipality about ways of tapping into public sewage systems or separate sewage systems if possible.
3. Solid Waste Materials
The second biggest cause of stormwater pollution comes from solid waste at construction sites. This waste includes leftover debris, garbage, and non-biodegradable materials, such as concrete and plastics.
Identify all sources of solid waste materials on construction sites and implement proper protocols to dispose of or recycle waste materials. Ensure no waste materials are lying around and that all receptacles have proper lids to prevent waste from being mixed with runoff.
While solid waste is typically a large culprit of stormwater pollution, it’s also the easiest to prevent through simple control measures and BMPs.
4. Hydrocarbons
Construction sites are run by heavy equipment that requires fuels and different additives to function. Unfortunately, hydrocarbons from gas, oil, and lubricants can cause substantial damage to local ecosystems if they are exposed to oncoming runoff.
It’s essential to establish refueling stations away from worksites and to designate proper storage locations to house fuels and hydrocarbons.
5. Nutrients
Organic waste from food, fertilizers, or natural sediment can be a major source of pollution for stormwater runoff, whether from a commercial construction zone, farm, or any commercial project involving these materials. In addition, organic debris from disturbed areas, such as leaves, grass clippings, and flowers, can also be a great source of pollution and turbidity.
It’s important to dispose of any leftover lawn debris from any landscaping that may be done on a site. Many of these materials can also be used as mulch to help protect bare soil from erosion.
6. Heavy-Metals and Building Materials
Construction sites are home to several dangerous and heavy metals, such as copper, zinc, and iron. Etc. In addition, building materials like concrete, stucco, and brick can also be significant polluters if not properly stored. Create a designated concrete washout station to prevent any unnecessary exposure of these dirty materials to rainwater.
7. Construction-related Dust
Finally, dust generated from cutting, grinding, or demolition can settle on surfaces and be carried by stormwater. We recommend using water sprayer systems to clean vehicles with built-up dust and erect temporary barriers designed to capture airborne dust.
Stormwater prevention management can be complicated, but by properly educating your team in BMPs and identifying potential sources of pollution, you can make educating your SWPPP easy.
Additionally, by working with an environmental consultant, you can find the best control measures to ensure proper EPA compliance and protect the surrounding area from any sources of pollution.
FAQs
What is the purpose of an SWPPP?
An SWPPP is a regulatory requirement to control stormwater pollution, minimize erosion, and protect local ecosystems during construction activities.
Who is responsible for developing a SWPPP?
Typically, construction managers or environmental consultants prepare a SWPPP, which must be submitted to obtain an NPDES permit.
Are SWPPPs required for all construction projects?
SWPPPs are typically required for projects disturbing one or more acres of land or those near sensitive waterways.