Stormwater runoff continues to be a major contributor to water pollution within urban areas by carrying bacteria, nutrients, heavy metals, trash, and other pollutants through storm sewer systems into local waterways. As communities throughout the Mid-Atlantic continue to grow, green infrastructure has become an increasingly important solution for sustainable stormwater management, flood mitigation, and long-term infrastructure resiliency.
In Virginia, Maryland, and Washington, D.C., where Muller, Inc. operates, stormwater runoff significantly contributes to pollution in the Potomac and Anacostia Rivers, and the Chesapeake Bay. Runoff is also a considerable hazard for localities like Alexandria, Va., Ellicott City, Md., and other flood-prone communities. Many communities, including those in the D.C. metro region, have traditionally made use of gutter, pipe, and tunnel systems – known as gray infrastructure – to ensure stormwater is moved away from residential and commercial areas to local water bodies or treatment plants. This infrastructure is getting old in many areas, and its ability to deal with large volumes of stormwater is on the decline.
To help address these challenges, municipalities, developers, and commercial property owners are increasingly investing in green stormwater infrastructure systems that improve water quality, reduce runoff, and support more sustainable site development practices.
Key Takeaways
- Green infrastructure manages stormwater at or near the source, rather than moving it away through pipes and tunnels.
- Common systems include rain gardens, bioswales, permeable pavement, green roofs, and rainwater harvesting.
- Benefits include improved water quality, reduced flooding, groundwater recharge, and cost savings on capital infrastructure.
- In the Mid-Atlantic region, green infrastructure supports stormwater compliance and helps protect the Chesapeake Bay watershed.
What Is Green Infrastructure?
Green infrastructure refers to engineered systems and natural features designed to capture, filter, absorb, and manage stormwater runoff closer to where rainfall occurs. Unlike traditional gray infrastructure systems that move stormwater away quickly through pipes and tunnels, green infrastructure helps slow runoff, improve infiltration, and reduce pressure on stormwater systems.
Common examples of green infrastructure include:
- Rain gardens and biotention facilities
- Bioswales and vegetated swales
- Permeable pavement systems
- Rainwater harvesting systems
- Green roofs
- Stormwater retention and detention systems
Green infrastructure is able to filter and absorb stormwater where it actually falls, and elements of green infrastructure are able to be woven into communities at a number of different levels. Urban examples include rainwater harvesting, planter boxes on a city street, or an alleyway being “greened.”
- In neighborhoods, green infrastructure might include open park spaces outside the city center, the installation of permeable pavements, or the planting of rain gardens close to residential housing.
- In landscaping, examples include the protection of wetlands, large open natural spaces, riparian areas, or the greening of steep hills.
- For commercial developments, mixed-use projects, data centers, and municipal infrastructure, green infrastructure practices can also help support stormwater compliance requirements while improving long-term site resiliency.
The installation of green infrastructure throughout a community or city can also offer cleaner air, water, and other value to the community, such as beautiful green spaces, diverse habitats, and flood protection.
Benefits of Green Infrastructure
Green infrastructure provides environmental, economic, and operational benefits by helping manage stormwater at its source rather than relying entirely on traditional drainage infrastructure.
The primary purposes of green elements are the reduction and treatment of stormwater at its source while delivering economic, environmental, and social benefits. The introduction of green infrastructure as a supplement to existing infrastructure can help promote urban livability while also adding to the bottom line of communities.
How Green Infrastructure Improves Water Quality
Pollutants such as heavy metals, nutrients, pathogens, and sediment are transported to beaches, lakes, and streams by stormwater runoff from urban areas. In cities like Washington, D.C., and Alexandria, Va., that have combined sewer systems, untreated sewage can also be sent into the water by high stormwater flows.
Retaining rainfall from small storms via green infrastructure results in a reduction of stormwater discharges, with lower volumes of discharge translating into a reduction in combined sewer overloads and lower pollutant loads.
Many green infrastructure systems, including bioswales, rain gardens, and permeable pavement systems, also naturally filter pollutants before runoff reaches local waterways.
Stormwater that does not get retained is also treated by green infrastructure.
How Green Infrastructure Reduces Flood Risk
Standard stormwater infrastructure sees stormwater quickly drained into rivers and streams, which increases peak flows and the risk of flooding. However, green infrastructure can mitigate flood risk by slowing down and reducing stormwater discharges.
This is especially important in urban environments where large areas of impervious surfaces create excessive runoff during heavy rainfall events. Green stormwater infrastructure helps reduce localized flooding while supporting more sustainable drainage systems.
Water Supply and Groundwater Recharge=
Infiltration practices and stormwater harvesting can significantly increase the efficiency of water supply systems. Water collected via stormwater harvesting systems can be used for exterior irrigation with some interior uses and dramatically reduce municipal water use.
Water infiltrated into the soil can also result in the recharging of groundwater.
Cost Savings for Developers and Municipalities
Stormwater management systems based on green infrastructure instead of the traditional gray infrastructure can often save developers on capital costs. These savings are the result of reduced costs of on-site grading, landscaping, paving, and smaller requirements as well as the elimination or reduction of detention and piping facilities.
Cities with combined sewer systems can also save money given that green infrastructure controls are less expensive than conventional ones, and a mix of gray and green infrastructure can cut down public expenditures in regard to stormwater infrastructure.
For developers and municipalities, integrating green infrastructure early in the site development process can also help reduce long-term maintenance demands and improve stormwater system performance over time.
Rainwater Harvesting
Rainwater harvesting systems cut down on stormwater pollution by slowing down runoff and collecting rainfall to be used later on. The wide array of systems can range from a simple backyard rain barrel and commercial building cisterns to aquifers, ground-level pits, and nets that are able to capture fog and dew. These systems have been implemented all over the world.
Green Infrastructure vs. Gray Infrastructure
| Gray Infrastructure | Green Infrastructure |
| Moves stormwater away quickly via pipes and tunnels | Slows, absorbs, and filters stormwater close to the source |
| Relies on storm sewers, culverts, and detention basins | Uses rain gardens, bioswales, permeable pavement, and green roofs |
| Higher long-term capital and maintenance costs | Can reduce on-site grading, piping, and detention costs |
| Aging systems in many Mid-Atlantic communities | Supports long-term resilience and regulatory compliance |
In many modern site development projects, green and gray infrastructure systems are used together to create more resilient and sustainable stormwater management solutions.
Common Green Infrastructure Applications
Green infrastructure can be integrated into a wide variety of residential, commercial, municipal, and industrial projects, including:
- Commercial and mixed-use developments
- Data center site development
- Municipal roadway projects
- Residential communities
- Parks and recreation areas
- Stormwater retrofits and redevelopment projects
These systems are often incorporated alongside stormwater ponds, drainage swales, underground stormwater systems, and other site development infrastructure to improve long-term environmental performance and regulatory compliance.
Why Green Infrastructure Matters for Stormwater Compliance
As environmental regulations continue evolving throughout the Mid-Atlantic region, many municipalities and developers are looking for sustainable stormwater management strategies that support both compliance and long-term infrastructure reliability.
Green infrastructure practices can help reduce runoff volume, improve water quality, and support compliance with local stormwater management requirements while helping protect sensitive waterways like the Chesapeake Bay watershed.
Partner With Muller for Green Infrastructure Solutions
Muller, Inc. has been a leader in green infrastructure and sustainable stormwater management for over fifteen years, offering expert services throughout Northern Virginia, Maryland, and Washington, D.C.
From stormwater maintenance and drainage improvements to turnkey site development and green stormwater infrastructure solutions, Muller helps developers, municipalities, and commercial property owners build more resilient and sustainable sites throughout the Mid-Atlantic region.
To learn more about Muller’s green infrastructure and stormwater management capabilities, contact our team today.
