4 Ways Permeable Paving Provides Better Stormwater Management
During a large weather event, like a thunderstorm, hurricane or snowstorm, the sheer volume of run-off produced by the rain or melting snow can create many problems, not only for your property, but for surrounding properties, the local municipality and the environment.
On your property the storm water can create localized flooding on hard surfaces like driveways, parking areas or fire lanes that are made out of asphalt or concrete, possibly causing damage to parked vehicles, structures or any other property located in, or adjacent to, the flooded area. Such damage could cause expensive repair bills, claims against your insurance policy, or even lawsuits under certain circumstances. The high volume of water can also damage the surface itself, by exploiting and worsening existing weaknesses like cracks or pot holes, or by undermining the asphalt or concrete surface and causing it to collapse.
When storm water moves at a high velocity, such as during heavy thunderstorms, it can also cause serious problems with erosion, both on your property and on surrounding properties. This can be especially problematic on slopes and hills, causing instability that could lead to landslides and property damage. In addition, the top layer of soil often contains the greatest amount of nutrients, so when it is washed away, the area will need new topsoil to provide the proper nutrients for new plants. The storm water can also accumulate dangerous chemicals from the surfaces it passes over, such as oil from paved roads, causing environmental concerns, and the large volume of water can overwhelm municipal waste water systems, causing them to clog or overflow, contributing to increased flooding.
To avoid these problems, many industrial, commercial and residential areas are now using permeable paving solutions that allow water to naturally drain through the paved surfaces, much like it drains through the natural soil lying underneath it.
This has several advantages when it comes to storm water management:
#1 Less Flooding
Permeable paving solutions have surfaces made from gravel, crushed limestone or grass, allowing any water that collects on the surface to easily drain through to the surface below. During a heavy rain event, like a hurricane or thunderstorm, this significantly reduces the chance that the water will accumulate to extremely high levels, and prevents damage to structures or property in low-lying areas. It also reduces the amount of extra water contributed to nearby roads, reducing traveling hazards. With the reduced volume of water, effectively controlling any run-off is a much easier job, requiring less expensive infrastructure such as storm drains and pipes.
#2 Reduced Erosion
By reducing the amount of water running off paved surfaces, the amount of erosion can be significantly reduced in the areas surrounding the paved area. This can improve soil conditions in the surrounding area by maintaining important nutrients, and it can reduce the amount of sediment collected in nearby storm water collection systems, both private and municipal. Additionally, permeable pavers can be used with either gravel or grass fill to protect erosion-sensitive areas, such as slopes or hills, by covering them with a flexible, permeable surface that hold the underlying soil layer in place, no matter how much it is raining. This keeps the soil healthy and prevents desertification.
#3 Less Water in the Municipal System
In areas with municipal waste water systems that are over-taxed, permeable paving solutions help reduce the amount of water coming into the system, which could prevent, clogs, overflows and other problems, such as potable water contamination. By protecting erosion-prone areas with permeable pavers, the amount of sediment flowing into storm drains can also be reduced, preventing clogs and reducing maintenance. For commercial or industrial building projects, permeable paving can also reduce building costs, because many of the costly storm drains and pipes can possibly be eliminated.
#4 Fewer Environmental Consequences
Run-off from parking lots, commercial and industrial buildings often contain chemicals that are not particularly healthy or safe for either humans or the environment. By allowing water to soak into the earth naturally, instead of running into storm drains, permeable pavers can help keep this contaminated water out of the municipal waste water system, where it can be hard and quite expensive to dispose of safely. This could reduce costs for both the city and its residents.
Compared to asphalt or concrete, permeable paving solutions are a great way to provide paved areas, extra parking, fire lanes and unique landscaping to a building project without worrying about major storm water run-off problems in the future. This permeability also allows them keep natural groundwater where it is needed, replenishing the local soil and filling the natural aquifers that are used to supply drinking water.
Another great feature of permeable pavers is that they are made from recycled material that is extremely lightweight and strong. This allows them to easily be shipped to the jobsite and assembled with minimal manpower. They can be filled with either gravel, limestone or sod to create an instant durable surface that can be used by any vehicle, including heavy equipment. The paved area can be permanent, or it can be made temporary and easily removed after an event where extra parking is needed.
With gravel, sod or grass the permeable paving system can also be used to provide durable landscaping and erosion control for any type of building, residential or commercial. By encapsulating the gravel or grass in the permeable paving solution, the amount of maintenance is greatly reduced. Soil or gravel no longer has to be periodically added and the grass can be trimmed with a regular mower. The paving solution keeps the surrounding soil in place and watered-properly, preventing erosion and keeping the landscaping looking perfect at all times.
Permeable paving solutions are a great way to add the paved areas you need to your project without the cost, the maintenance requirements, or the storm water management difficulties that often come with the use of more traditional materials, such as asphalt, concrete or loose gravel. They can be installed quickly and easily, and provide a surface that performs better than traditional materials in many situations.
Sources:
http://truegrid2.jfcserver.de/resources/installation/
http://www.lowimpactdevelopment.org/
http://www.greenparkingcouncil.org/featured/manifesto-future-parking-lots/