What Is An Impervious Surface & Why Does It Matter?

From roads and parking lots to rooftops and sidewalks, impervious surfaces are a common feature of urban landscapes. While essential for transportation and development, these surfaces can create significant environmental challenges.

What Are Impervious Surfaces?

Impervious surfaces are areas that resist water absorption, causing rainwater to flow off rather than soak into the ground. Common examples include:

• Roads
• Parking lots
• Sports fields
• Patios
• Rooftops
• Sidewalks

These surfaces are essential for our daily lives but can have unintended consequences for local water systems and the environment.

Why Are Impervious Surfaces a Problem?

When rainwater can’t naturally absorb into the soil, it accumulates on impervious surfaces and flows directly into storm drains. This process disrupts natural water cycles and creates risks for both water quality and urban infrastructure. The two main issues are:

1. Increased Flooding

Impervious surfaces cause irregular runoff patterns, increasing flood risks in urban areas. Rapid water runoff from these surfaces can erode stream banks, change natural water flows, and lead to more frequent, severe flooding.

2. Water Pollution Concerns

Pollutants that accumulate on impervious surfaces are washed into storm drains and ultimately into natural water sources. Substances like oil from vehicles, pesticides from landscaping, and even animal waste on sidewalks contribute to this pollution, impacting water quality for both humans and wildlife.

What Can You Do to Help?

Reducing the impact of impervious surfaces can benefit both your property and the environment. Here are some effective solutions:

Use Permeable Materials: Choose materials like gravel, mulch, grass pavers, or uncemented bricks for pathways, patios, and driveways.

Implement Green Roofing: Plant vegetation on your rooftop to help absorb rainwater and reduce runoff.

Minimize Structure Footprints: Reduce the square footage of impervious surfaces, such as decks, patios, and driveways, on your property.

These strategies can help curb flash flooding and improve water quality by allowing rainwater to infiltrate the ground naturally.

Partner with iSTORMWATER for Effective Solutions

If you’re concerned about impervious surfaces around your home or business, contact the stormwater experts at iSTORMWATER. We specialize in preventative stormwater maintenance and flood mitigation to protect your property from potential water damage. We’re here to help with personalized advice and effective solutions.

For a free consultation on stormwater management solutions in DC, Maryland, and Virginia, call iSTORMWATER at (410) 231-3455 today!