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Reducing Impervious Surfaces

Impervious surfaces such as driveways, roads, parking lots, patios, and walkways do not allow rainwater to pass through the substrate into the ground. Instead, they cause rain water to run off at an increased speed, causing increased erosion, picking up pollutants (pesticides, sediment, and nutrients), and carrying them to the storm drains, then ultimately to rivers and streams. These surfaces can be replaced with pervious options including brick pavers, pervious concrete, turf stones, or gravel. These options allow polluted rainwater to move through these surfaces and into the soil where it naturally filters the water before returning to the groundwater.