Stormwater and Drainage Infrastructure Solutions

Stormwater runoff is a valuable natural resource, but it can also wreak havoc on a community.

In the best-case scenario, it soaks into the ground, replenishing groundwater resources. When it doesn’t excessive water can cause erosion, flooding, and pollution. As well, climate change, which brings sea level rise and heightened storm activity and flood events, increases runoff, and creates additional nutrient management issues.

While stormwater management is essential to every community, the drivers for a sustainable and comprehensive stormwater program are diverse. Your community is equally unique. From source areas and topography to land use and space limitations, there’s no universal approach to your needs. That’s where Gannett Fleming can become a partner.

The Regulatory Labyrinth

Regulatory compliance for environmental protection is a critical driver for any stormwater and drainage systems program. It ensures communities improve the water quality in their lakes, rivers, ponds, streams, reservoirs, and even the ocean.

Absent compliance, communities subject themselves to possible fines, consent orders, and other regulatory enforcement action. We help you, our clients, understand the obligations under federal, state, and local regulations. We develop sustainable solutions that ensure stormwater infrastructure and related water quality programs are in alignment with the Clean Water Act, Municipal Separate Storm Sewer System (MS4), Total Maximum Daily Loads (TMDL), and National Pollutant Discharge Elimination System (NPDES) permits.

You’re better able to focus on your core priorities when you rely on our team to help you:

  • Navigate the regulatory labyrinth.
  • Remain compliant.
  • Avoid costly sanctions and fines.

Resilient & Green Infrastructure

Gannett Fleming has been recognized by Engineering News-Record (ENR) as one of the nation’s top green design firms. This recognition comes through our stormwater work in the energy, water, waste, transportation, and air industries.

We envision green stormwater solutions beyond gray infrastructure, with concepts that mimic natural stormwater management processes. Our team provides forward-thinking solutions in low-impact development and stormwater best management practices. We do this to:

  • Mitigate primary pollutants at the source.
  • Promote the recharge of groundwater.
  • Reduce the occurrence and severity of combined sewer overflows.
  • Help make communities more resilient.

From bioretention facilities and capture and reuse systems to regenerative step pool conveyance systems and vegetated swales and filter strips, we’ll work to achieve your goals in the most economically, socially, and environmentally responsible way possible.

Watershed Planning

Perhaps your watershed is impaired or is impacted by flooding. Or, perhaps your community already enjoys a well-maintained watershed as a source of clean water for utility and recreational uses. In either case, watershed planning plays a vital role in the health of your community.

We can help you understand and manage the interaction between the environmental and manmade elements within your watershed. Doing so allows you to achieve, or simply maintain, a high-quality and sustainable watershed. We partner with communities like yours to develop a comprehensive framework for:

  • Reducing flood risk.
  • Restoring impaired waterways.
  • Protecting overall watershed health.

Our innovative, sustainable solutions employ natural processes to eliminate constrictions, decrease pollutant loadings, and restore and maintain watershed health. From visioning and goalsetting through funding and program implementation, our watershed planning services can provide a flexible foundation for your community’s evolving needs.

Asset Management

Aging stormwater infrastructure is a concern for counties and municipalities across North America. With limited funding and resources, many communities find themselves in a reactive position. We help clients overcome these barriers and migrate to proactive, long-term, and sustainable approaches to asset management.

Asset inventory is the first step in building an effective asset management program. We harness the power of technology to identify each of your stormwater assets. Using drone technology and geospatial information, we develop real-time geographic information system (GIS) maps that:

  • Eliminate outdated paper maps.
  • Increase accuracy and efficiency.
  • Aid in communication and knowledge transfer.

We put this information at your fingertips, with custom mobile applications accessible in the office or in the field.

Condition assessments also are a critical component of an effective asset management program. Our team of investigators can determine how your assets are performing, their remaining useful life, the risk associated with each, and repair and replacement costs. This information will become the foundation upon which a compelling business case for your stormwater investments may be built. Armed with complete inventory and condition data, Gannett Fleming can help you build a formal asset management program. Once in place, this program will drive informed decisions and become the cornerstone of your stormwater capital program.

Stormwater & Drainage Solutions Include:

  • Asset management.
  • Best management practice retrofits.
  • Combined sewer overflow control planning.
  • Construction management.
  • Conveyance design and analysis.
  • Detention & retention facility design & analysis.
  • Drone surveys.
  • Flood mitigation solutions.
  • Geographic information systems.
  • Grant-writing & project funding strategies.
  • Green infrastructure.
  • Ground penetrating radar.
  • Hydraulic & hydrologic modeling.
  • Low-impact development planning.
  • Master planning & watershed studies.
  • NPDES & MS4 compliance & permitting.
  • Neighborhood flooding.
  • Stormwater pollution prevention planning.
  • Stormwater utility development.
  • TMDL analysis & compliance.
  • Utility rate structure development.
  • Water quality analysis & monitoring.


Are you looking for a reliable, collaborative partner? Do you have a planning, design, or construction challenge? We want to hear from you.

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Are you looking for a reliable, collaborative partner? Do you have a planning, design, or construction challenge? We want to hear from you.

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