Over its lifetime, pervious concrete can be a much more inexpensive option than traditional concrete, even though the installation cost of pervious is typically higher than that of traditional concrete.
The money savings are because pervious concrete can lower the overall costs of residential and commercial projects by reducing the need for special drainage features. Because pervious concrete allows rainwater to drain directly through to underlying soil, less stormwater management is needed. Pervious concrete also requires less repair maintenance than some other paving options, including asphalt.
Here’s a breakdown of the cost comparisons with pervious concrete installations:
Installation cost: The initial cost of a pervious concrete driveway or parking lot in Whatcom County might be two to three times that of a traditional concrete driveway. This is primarily because pervious concrete is laid thicker — around 6 inches or so, generally, compared to 4 inches for traditional concrete — and more needs to be done to prepare the concrete base for water infiltration. The materials themselves cost about the same, but the difference is in the preparation.
Maintenance cost: The cost of maintaining pervious concrete over time is similar to the cost for traditional concrete. All types of concrete need to be maintained to remain in top shape. However, it should be noted that other types of paving surfaces might cost more over time due to higher maintenance costs. A typical asphalt installation is one example. According to one study from the University of California-Davis, the upkeep of asphalt over its lifetime “makes it a more expensive choice than permeable pavements, without offering the benefit of water recharge and filtration.” That study calculated that the money saved by installing permeable pavements instead of asphalt is nearly $65,000 per half-acre over 25 years.
Cost of other features: If a concrete installation needs to include systems for handling water runoff, pervious concrete can lead to large savings over time. Pervious concrete installations can actually act as water retention systems in many cases, since they handle large amounts of water and allow it to filter deep into the earth. “Pervious concrete roadways and parking lots can double as water retention structures,” according to the Concrete Network, “reducing or eliminating the need for traditional stormwater management systems such as retention ponds and sewer tie-ins.” Believe it or not, as much as 5 gallons of water per minute can pass through a square foot of pervious concrete. A house with 2,500 square feet of roof area, in a storm that dumps an inch of rain over six hours (classified as a “very heavy” rainstorm), is collecting a little more than one and a quarter gallons of water per minute. That’s a lot of water, even for Bellingham, which averages less than 40 inches of rain per year. With the aid of pervious concrete, however, it’s possible to handle all of it without even taxing the city’s stormwater system. In fact, all of that rain could filter through a single square foot of pervious concrete.
Environmental costs: According to the Environmental Protection Agency, pervious concrete helps to eliminate pollution by helping to filter out pollutants collected by rainwater. The environmental benefits of pervious concrete might not show up on your bill — other than potential savings in stormwater management and treatment, of course — but you’ll still appreciate that your concrete driveway installation is doing good for the environment.
One thing we didn’t mention is that using pervious concrete instead of traditional might actually allow you to use more of your property for buildings. That’s because pervious concrete doesn’t count toward your impervious surfaces limit.
For more information about pervious concrete installations in Whatcom and Skagit counties, give Custom Concrete Contracting in Bellingham a call! We are experts in local pervious installations.