Avoided over $17 million dollars in construction costs using Green Infrastructure in lieu of Gray Infrastructure for CSO control.

Over $12 million dollars in grants written for flood control green infrastructure.

CSO And Flood Control

No matter the scale or budget, green infrastructure can be a cost-effective flooding and Combined Sewer Overflow (CSO) control alternative. We have the on-the-ground experience with changes in rainfall intensities/duration to develop a holistic, phased approach to build community resiliency.

Green and Blue Infrastructure practices mimic natural hydrologic processes to reduce the quantity and/or rate of stormwater flows into the combined sewer system, therefore reducing combined sewer overflows to our lakes and streams. By controlling stormwater runoff through the processes of infiltration, evapotranspiration, and capture and use (rainwater harvesting), Green and Blue infrastructure can help keep stormwater out of the CSO. 


Green and Blue Infrastructure can be utilized at varying scales— at the site and/or watershed level. For example, small source control practices such as bioretention, porous pavements, green/blue roofs, tree trenches, infiltration trenches, reforestation, and rainwater harvesting can fit into individual development, redevelopment or retrofit sites. Larger scale management strategies such as constructed stormwater wetlands, subsurface gravel wetlands, oxbow restoration, and large infiltration/attenuation systems can be used at the subwatershed or watershed level.

CSO and Flood Control Services

  • CSO Abatement Green Infrastructure and Expert Witness Support
  • Stormwater Control Measures (SCMs)
  • FEMA Floodplain Determination and LOMR
  • Hydraulic and Hydrologic Studies
  • Green and Complete Streets
  • Green Infrastructure Retrofits
  • Inspection, Maintenance, and Repair
  • Green Infrastructure Post Construction Monitoring
  • Integrated Plan Green Infrastructure Support
  • Stream and Wetland Restoration