You can use permeable or porous paving as a source control measure for small roads, pavements, car parks and yards. Source control measures are sustainable drainage systems (SUDS) that deal with run-off at, or close to, the surface where rainfall lands.
Rain passes through the surface, either through gaps between individual blocks or permeable material such as gravel or porous asphalt, trapping pollutants below. Once there, many pollutants are broken down by natural processes.
By using permeable paving you can also prevent water pooling on impermeable surfaces, avoiding puddles and ice on car parks.
Large amounts of water can be stored temporarily under the surface. This reduces the chances of flooding.