How Stormwater Runoff Impacts Water Quality

Stormwater runoff isn’t just a nuisance – it’s a major threat to water quality, public health, and local ecosystems. As rain falls or snow melts, it flows over impervious surfaces like rooftops, roads, and parking lots, collecting a mix of harmful pollutants. These contaminants are then carried into nearby streams, rivers, and lakes, degrading water quality and harming aquatic life.

At iSTORMWATER, we help commercial property owners, developers, and municipalities across Maryland, Virginia, Washington, DC, and Delaware manage stormwater runoff responsibly and cost-effectively.

What Is Stormwater Runoff?

Stormwater runoff is water from precipitation – rain or melting snow – that doesn’t soak into the ground. Instead, it flows across hard, non-porous surfaces such as asphalt, concrete, and compacted soil. As it flows, it picks up pollutants like:

• Motor oil and grease
  
• Heavy metals
  
• Sediment and debris
  
• Fertilizers and pesticides
  
• Pet waste and litter
  
• De-icing salts
  

This polluted runoff eventually enters storm drains, which often lead directly to local water bodies without treatment. Unlike sanitary sewer systems, stormwater systems typically don’t filter or treat water before discharge, making proactive management essential.

How Stormwater Runoff Degrades Water Quality

When runoff enters waterways, it introduces contaminants that:

• Reduce oxygen levels, harming fish and aquatic organisms
• Disrupt plant growth by increasing turbidity and altering nutrient levels
• Spread bacteria and toxins that pose health risks to humans and wildlife
• Increase flooding and erosion, damaging stream banks and habitats

Stormwater pollution is one of the leading causes of water quality impairment in urban and suburban areas. It’s also a key compliance concern under the Clean Water Act, particularly for commercial property owners subject to MS4 (Municipal Separate Storm Sewer System) permits and other state-level stormwater regulations.

5 Common Pollutants Found in Stormwater Runoff

Here are some of the most common and harmful pollutants that runoff can carry into your local water supply:

1. Sediment
   Sediment clogs waterways, smothers aquatic habitats, and transports toxins. It can increase water temperature and reduce clarity, impacting aquatic plant photosynthesis and fish feeding behavior.
2. Oil and Grease
   These hydrocarbons form a slick on the water’s surface, cutting off oxygen exchange and stifling aquatic life. Even small amounts can disrupt ecosystems.
3. Pesticides and Fertilizers
   Excess nutrients from fertilizers fuel algal blooms, which can create dead zones by depleting oxygen. Pesticides are toxic to aquatic organisms and may bioaccumulate in the food chain.
4. Road Salts
   Used for de-icing, salts (primarily sodium chloride) raise salinity in freshwater systems. This can kill fish, amphibians, and beneficial aquatic insects.
5. Heavy Metals
   Runoff can contain lead, copper, arsenic, and cadmium from vehicle wear, industrial sources, and construction sites. These metals are toxic to both aquatic life and humans.

Why Stormwater Management Matters

Effective stormwater management is essential to preserve the purity of our region’s waterways. By implementing and maintaining appropriate infrastructure, businesses can:

• Comply with local, state, and federal regulations
  
• Avoid costly fines and enforcement actions
  
• Reduce liability from flooding and water damage
  
• Protect natural ecosystems and biodiversity
  
• Demonstrate environmental stewardship to the community
  

At iSTORMWATER, we deliver turnkey stormwater solutions tailored to your property’s specific risks and regulatory needs.

Solutions for Preventing Stormwater Pollution

✅ Aboveground Stormwater Facilities

These structures manage runoff on the surface and include:

• Stormwater management ponds
  
• Bioretention facilities
  
• Infiltration basins
  
• Sand filters
  
• Extended detention basins
  

✅ Belowground Stormwater Facilities

Installed beneath parking lots or landscapes, these include:

• StormFilters
  
• Underground detention vaults
  
• Aqua-Swirl™ treatment systems
  
• BaySaver® separation systems
  

✅ Routine Stormwater Maintenance

Regular maintenance ensures your systems function correctly and stay compliant. This includes:

• Inspections
• Repairs
• Debris removal
• Vegetation control
• Performance assessments

✅ Flood Mitigation

More intense storms are becoming the norm. Proactive flood mitigation – such as installing retention basins, swales, or permeable pavers – helps reduce runoff volume and protect your site from property damage.

Our Certifications & Commitment to Compliance

iSTORMWATER is fully certified to deliver stormwater solutions that meet environmental regulations in the mid-Atlantic region. Our team holds:

• Erosion and Sediment Control Certification
  
• Stormwater Management Inspector Certification
  
• Stormwater Maintenance Facility Contractor Certification
  

All work is performed by trained professionals and backed by our commitment to integrity, transparency, and long-term value.

Schedule Your Stormwater Consultation

If your property has outdated or underperforming stormwater infrastructure, now’s the time to act. iSTORMWATER provides free consultations, expert inspections, and tailored recommendations to protect your site and local waterways.

📍 Serving Maryland, Virginia, Washington, DC, and Delaware
📞 Call us at (410) 231-3455 or 💬 Contact us online .