Permeable Pavement

What is Permeable Pavement?

Best Location

Permeable pavement works well on driveways and walkways that have:

• Flat areas with less than a two percent slope (two-foot drop in elevation for every 100 feet);
• Soil with a high infiltration rate (allows water that is temporarily stored in the pavement to soak into the ground);
• Little tree cover – tree roots or overhanging tree canopy can negatively impact the pavement; and,
• Small spaces (Many stormwater features require a large footprint).

There are different types of permeable pavement. Talk with your contractor to see what's the best fit for your property.

Removing Pavement

Concrete driveways are not pervious. This causes rainwater to flow off the driveway rather than into the ground.

Why remove it?
Removing this pavement creates less stormwater runoff, which is better for our streams.

Soil Tests

You will need to complete a soil test on your property to see if the conditions are right for this type of pavement. The test results are used to determine the size and depth of the pavement to make sure that the soil can support the system. A licensed soil scientist must complete these tests. They determine the following for your project:

• Infiltration rate;
• Soil type; and,
• Seasonal high water table (the level that groundwater rises in the soil during a wet season)

Raleigh Rainwater Rewards participants will need to pay for the soil test up front. The cost of the test may be eligible for reimbursement after your project is approved and completed. 

Benefits

Permeable pavement spreads out stormwater, soaks it into the ground, and slows it down.

Reimbursement

You can be reimbursed through our Raleigh Rainwater Rewards Program when you “upgrade” an impervious footprint to a permeable pavement system.

Reimbursement does not include the cost of:

• Removing the existing impervious surface; 
• Installing traditional pavement in the same footprint; and, 
• Projects used to meet stormwater requirements for development. 

Calculating your Reimbursement

How it's calculated: 
(Permeable pavement cost) – (Traditional pavement cost) x (Reimbursement percentage)