It’s no secret that mankind has a significant impact on the environment, especially in construction. Reshaping the land affects local ecosystems and more. And even after a project has been completed, it will continue to clash with nature.
One way this occurs is through the flow of stormwater and melted ice or snow. Water doesn’t discriminate, dragging everything it touches along for the ride until it is eventually discharged into a river, lake, or sewer.
Stormwater management plans are designed to risk pollution from runoff and are legally required for most construction projects that discharge into public waters.
This article will detail the basics of a stormwater management plan, including its most important aspects so that site managers are properly prepared.
Why Is It Essential to Manage Stormwater?
Whenever we excavate, flatten, or develop land, we disrupt nature. That’s not exactly a surprise, but one factor we cannot overlook is how disrupting the land affects stormwater flow.
The fact that the shape of the land disrupts the natural flow of water and its ability to soak into the ground is nothing to take lightly. Limiting and impeding these abilities can create various problems for the surrounding ecosystem and infrastructure, but it’s not the only issue.
Contamination of water runoff is just as, if not more, pressing as the flow. Regardless of whatever is in the way, water will find a way to continue its flow to a natural body of water. As it rolls over rooftops, sidewalks, and other impermeable surfaces, any harsh chemicals in these places will pollute the water.
If those chemicals reach local natural water bodies, they can harm and potentially kill any plant or wildlife within or even nearby. And because those water bodies may be a source of drinking water, nearby people are at high risk.
Therefore, doing everything we can to control the flow of stormwater runoff and what it comes in contact with is imperative for preserving local ecosystems.
Common Issues Caused By Stormwater Runoff
Even the smallest construction projects are bound to create significant water runoff problems. These are a few examples of why every construction project is responsible for eliminating its impact on rainwater from beginning to completion and beyond.
Below, you will find a list of the problems stormwater runoff can create:
- Pollution: As water flows over the top of the surfaces in place, it will collect chemicals on top. Construction sites host countless harmful substances that can cause severe damage if they enter a natural body of water. The ecosystems within will suffer, and it can even cause contamination of drinking water.
- Erosion: As water flows off impervious surfaces, it will find new paths. Water moves over land in a way it never has before. This can cause deterioration that may also be detrimental to ecosystems and the local community.
- Flooding: Without proper management in place, runoff stormwater will overflow drainage ditches, sewer systems, and storm drains. In any case, the excess flow of water is likely to lead to flooding.
- Turbidity: If the water makes its way to the ground that can absorb it, it too may be in excess. When this occurs, it can cause turbidity or muddiness, ruin nearby land, or starve aquatic life of the sunlight needed for survival.
- Infrastructure Damage: Flooding, erosion, pollution, and turbidity can wreak havoc on the local infrastructure. It’s not uncommon for a construction site without stormwater management plans to damage or destroy it.
What Is a Stormwater Management Plan?
A stormwater management plan–officially known as an SWPPP–is a formal document often required by the EPA or local permitting authority to acquire a permit to discharge stormwater runoff from an active work zone.
Stormwater management plans detail every aspect of a worksite, from the facilities’ name and date of the project to any equipment being used and pollutant sources nearby.
Most importantly, a stormwater management plan outlines active controls or BMPs that will be used to control stormwater runoff and reduce erosion/sedimentation.
What’s the Difference between SWPPP and SWMP?
The fundamental difference between a SWPPP and a SWMP is that the former is temporary, while the latter is permanent. The SWPPP is intended to solve any potential issues regarding the flow and quality of stormwater during a project’s construction, while the SWMP is a permanent solution that deals with the matter once the project reaches completion.
The plan you develop requires a few critical bits of information. The necessary details regarding the size, location, and primary point of contact include all the required details. Other than that, you also need to fill in the details of any streams or tributaries, lakes, water tables, and major rivers that the site is nearby and may impact.
As with an SWPPP, the SWMP requires you to detail any methods by which you intend to manage the flow and quality of water runoff using minimum control measures and Best Management Practices, or BMPs. After completion, the plan must be submitted with a Notice of Intent and reviewed for approval to obtain a National Pollution Discharge Elimination System permit.
The Benefits of a Stormwater Management Plan
Stormwater management plans may involve some added red tape, but they serve a crucial purpose for site operators and the surrounding community.
Water Quality
We might have mentioned pollution already, but it’s essential to remember that these systems do more than ensure the excess water flow is under control. Even if the water is directed in the proper location, it likely isn’t clean. Remember, it’s carrying along any debris or chemicals that it can collect along the way. Therefore, protecting water quality is just as crucial to the process as any other.
Filtration of pollutants is critical to ensure drinking water and local ecosystem sources of drinking water are not contaminated.
How filtration is achieved is ultimately dependent on the system in use. MS4s, for example, use filters throughout the system to prevent chemicals or debris from following the water to its final destination. On the other hand, biofiltration swales use biological filters, such as grass, to perform the same task.
Reduced Flooding Risk
Flooding is one of the most dangerous risks for construction sites that experience heavy rainfall. A proper stormwater management plan provides measures to reduce the risk of flooding by diverting rainwater away from areas with higher concentrations, such as slopes or hills. This also reduces the risk of erosion, which can prevent pollution.
Regulatory Compliance
Creating a proper stormwater management plan can ensure proper compliance across all levels of governance, from federal to municipal oversight. Site managers who work with a proper consultant avoid exorbitant fines and ensure that construction activity is not delayed.
What System Do I Need?
The Environmental Protection Agency amended the Clean Water Act in the 1990s. Under this act, a national two-phase program is in effect to address water pollution caused by runoff stormwater.
Phase one of the program deals with stormwater discharges, while phase two deals with smaller Municipal Separate Storm Sewer Systems (MS4s). In short, this act determines what systems you must implement to deal with runoff.
Exactly how you manage stormwater to satisfy the Clean Water Act depends on a few factors. It’s tempting to believe that because there are already MS4s in place, all you need to do is tap into them.
However, these systems can only handle so much. An excess of water runoff can quickly lead to flooding or damage to the infrastructure, which is why there is a limit to how much water you can direct to them. That means you likely must come up with additional ways to manage stormwater.
Below is a list of other forms of stormwater management systems you can include in your plan:
- Bioretention Areas/Rain Gardens
- Constructed Wetlands
- Curb and Gutter Elimination
- Drainage Ditches
- Green Roofs
- Permeable Pavements
- Rain Barrels and Cisterns
- Riparian Buffers
- Sand and Organic Filters
- Vegetated Filter Strips
- Vegetated Swales/Dry Swales
Which of these solutions is acceptable for your project? How big do they have to be? There is room for creativity, meaning you can implement systems that complement your project’s layout or theme.
However, it depends on the project and your location, so it’s hard for us to provide you with any hard numbers. Your local county or city will have different requirements than others, and you need to follow the guidelines they can provide.
Beyond Installation
It’s important to remember that the effectiveness of a SWMP goes beyond the implementation of water management systems. Upkeep is essential to their function and efficiency. Periodic maintenance is necessary to ensure they can continuously deal with water runoff.
It says that maintenance, like all other things, is specific to the system(s) you are using. Stormwater drains and drainage ditches, for example, are subject to collecting debris as water flows to them. You must clear the waste and other deposits to prevent the system from clogging up and failing to perform its job.
Another example of maintenance is dealing with overgrowth in rain gardens, and biofiltration swales are essential to prevent similar debris from being caused in other systems. No matter your method, regular inspections will likely occur to ensure proper maintenance.
If you do not keep up with maintenance, these inspections can result in penalties and fines. However, that is usually a last-ditch effort to protect water flow and quality. The inspectors are likely to advise ways to improve maintenance long before taking other measures.
In the end, your stormwater management plan is a detailed document about your efforts to mitigate the impact of stormwater on a work site. It’s on you to implement the document’s systems and keep up with them.
But you should view these systems as more than requirements to keep a project moving. Putting these efforts into effect is how we can reduce our impact on the environment, effectively protecting the local land, wildlife, and residents.
Have any further questions? Contact Path Light Pro to talk with a trusted consultant today.
FAQs
What is a stormwater management plan (SWPPP)?
A stormwater management plan (SWPPP) is a detailed document that outlines strategies and practices for managing the runoff of rainwater or melted snow from urban areas, primarily to prevent flooding, erosion, and water pollution. The plan typically includes assessing current stormwater systems, identifying potential problems, and implementing solutions like detention basins, green infrastructure, and permeable surfaces.
Why is stormwater management important?
Stormwater management is crucial because it helps to control flooding, reduce erosion, and prevent pollutants from being washed into natural water bodies. Effective stormwater management protects both the environment and human health by maintaining the integrity of local water resources, supporting wildlife habitats, and reducing the risk of property damage from flooding.