Stormwater infrastructure is a critical component of any community. Defined as infrastructure to manage rainwater and snowmelt that runs over impervious surfaces and can lead to flooding, stormwater infrastructure includes concrete storm sewers, flood control reservoirs, roadside ditches, rain gardens, and other systems designed to reduce hazardous water flow. Currently in the US, there are approximately 3.5 million miles of storm sewers, 270 million storm drains, and 2.5 million stormwater treatment assets. All of this infrastructure varies in age, condition, and suitability for current land use, and requires constant maintenance by municipal public works departments.

Maintaining adequate stormwater infrastructure is top of mind for municipalities across the US as existing systems not only age, but are strained by land use change. The most common stormwater infrastructure has a lifespan of about 30 to 100 years, meaning many municipalities are now faced with replacing their original systems. In fact, the American Society for Civil Engineers has given US stormwater infrastructure an overall grade of D. However, community stormwater needs have drastically evolved in the same timeframe. Climate change has led to a rise in both the intensity and frequency of stormwater events, while population growth and community development have increased the amount of impervious surfaces found throughout the US. As a result, stormwater professionals are now tasked with developing and funding infrastructure improvements to not only maintain existing systems, but enhance them to be more resilient to dynamic climate and land use changes.

Ensuring stormwater infrastructure is up-to-date with current community needs is critically important, as ineffective systems can lead to costly and dangerous flooding events as well as water supply contamination. In 2022 alone, flooding caused about $2.8B in property and crop damage throughout the US and led to 91 deaths. What’s more, over 588,000 miles of river are considered impaired by poor stormwater management, severely degrading water quality for the surrounding population.

Geospatial analysis for stormwater management

While stormwater management is a complex topic largely dependent on a community’s specific needs, many municipalities leverage similar strategies to enhance resilience. For example, more than 2,100 municipalities across 42 states and Washington, DC have established stormwater utility fees (SUFs) to fund infrastructure maintenance and improvements. Similarly, geospatial data is increasingly used for insight into land use and how the distribution of impervious surfaces throughout a community impacts runoff and flood risk. 

As climates and communities vary across the US, so do the stormwater needs of municipalities. What is a top priority for a coastal community may be less important to an inland municipality, and vice versa. At Ecopia AI (Ecopia), we work closely with stormwater professionals around the world to develop geospatial data solutions that fit their distinct needs. Here’s a quick breakdown of how we see different regions of the US approaching stormwater management, including real examples from municipalities we support.

Stormwater management in the Northeast & Great Lakes region

Throughout the northeastern US and the Great Lakes region, municipalities must grapple with both coastal flooding and high precipitation levels from snow and rain storm events. According to the National Climate Assessment, rainfall intensity is increasing faster in this area than in other regions in the US. This increase in stormwater and proximity to coastal bodies of water makes the region particularly susceptible to flood events, making stormwater management a top priority for many municipalities. Additionally, this region is home to some of the nation’s largest and oldest urban areas. This not only means that many municipalities have older infrastructure in need of replacement, but also that there are high amounts of impervious surfaces contributing to increased runoff. The population of the Northeast and Great Lakes region is also still increasing, leading to more development and higher levels of impervious land cover throughout communities. Many older cities are experiencing urban revitalization, further contributing to changing land use. 

To combat these challenges, stormwater professionals are increasingly turning to geospatial data to analyze rapidly changing land use within the context of older infrastructure and more storm events. Many have chosen to create SUFs and flood models based on impervious surfaces, or even mitigate runoff by establishing green infrastructure like rain beds or stormwater medians. All of these stormwater management strategies require having an up-to-date understanding of land cover, which can be difficult to achieve in a rapidly changing world with traditional data creation methods. However, advancements in AI are enabling communities throughout the Northeast and Great Lakes region to efficiently maintain an updated source of truth for land use as a strategic tool to manage stormwater. 

See how AI-based mapping expedited impervious surface mapping by 18x in Detroit, Michigan.

Stormwater management in the Southeastern US

Similarly, the southeastern United States faces unique climate threats due to its susceptibility to extreme precipitation events, such as hurricanes and tropical storms or depressions. While stormwater from snowmelt is less of a risk in this region, there is still a significant risk of flooding from rainwater, especially in low-lying coastal areas. These areas are also experiencing the impact of global sea level rise, increasing the strain coastal flooding places on stormwater infrastructure. Not only does coastal flooding pose risks to properties and human lives, but its saltwater can quickly contaminate freshwater supplies when infrastructure is overwhelmed. In addition to these environmental risk factors, much of the southeastern population is concentrated along the coast. According to NOAA, one-third of the population of the southeastern US lives in a coastal county, with more than 4 million people living within a flood zone. 

While cities in the Southeast tend to be a little newer than some of the older northeastern cities, much of the stormwater infrastructure in this region is still in need of repair. This is due to both age as well as wear and tear, as the extreme climate conditions of the Southeast can place high stress on drainage systems. Land use change is also an issue in the Southeast, as this area is experiencing the highest population growth in the entire US. In 2023, the US Census Bureau reported that 9 of the 15 most rapidly growing cities in the US were in the Southeast, spread between Florida and Texas. With this population boom comes increased development and land use change, particularly expanding the amount of impervious surfaces contributing to higher runoff and flood risk. Like other municipalities across the US, southeastern communities are leveraging geospatial data to establish SUFs and perform climate analytics to increase resilience to both coastal and riverine flooding. Hazard mitigation is also top of mind, as many communities use geospatial data to both model risk and develop flood prevention strategies, such as curbing development, protecting wetlands, and building storm surge barriers. All of these strategic decisions require an up-to-date view of land cover, both impervious and pervious, which is now feasible and cost-effective to collect at more frequent intervals thanks to AI.

Read how the City of Jacksonville was able to save 84% on land cover data creation costs by working with Ecopia.

Stormwater management in the Pacific West

Municipalities in the Pacific West vary greatly in climate, but also share similar challenges when it comes to stormwater management. Like the Southeast, Northeast, and Great Lakes regions, many communities in the Pacific West are at risk of coastal flooding. According to NASA, the rapidly rising sea levels of the Pacific are amplifying the effects of El Niño, increasing the frequency of high-intensity coastal floods. Additionally, the northern part of this region is at an increased risk of flooding from snowmelt and extreme precipitation, while the southern area often experiences droughts and water scarcity. Both situations come with stormwater considerations that public works departments must oversee to ensure communities are safe, livable, and resilient. Another unique environmental component of the Pacific West is the region’s tectonic profile, which leads to a higher risk of earthquakes and subsidence than other areas of the US. These events not only pose risks to stormwater infrastructure, but also can exacerbate the effects of flooding by leading to dangerous landslides. 

While cities in this region are newer relative to most of their eastern counterparts, stormwater infrastructure is strained by rapid migration, population growth, and land use change. California is the most populous state in the US, while Washington and Oregon are among the most rapidly growing. Urban sprawl and development have led to an increase in impervious surfaces throughout the region, making communities less resilient to an increasing number of extreme weather events. In response, many municipalities are leveraging geospatial data to understand which areas are most vulnerable and implement mitigation strategies, such as green stormwater infrastructure and SUFs. While geospatial analysis is extremely helpful for flood modeling, it also provides valuable insight into water quality issues for stormwater professionals in water-scarce areas. However, the dynamically changing landscape in this region means data must be frequently updated to be useful.

Learn how the City of Seattle leverages Ecopia’s AI-powered land cover data for stormwater and climate resilience planning. 

Stormwater management in the western US

Unlike other regions, the western US does not grapple with the risks of coastal flooding. While these landlocked western states vary in climate, with some experiencing cold, snowy winters and others containing some of the world’s hottest deserts, they nonetheless all face stormwater challenges. Storms in the west are increasing in both frequency and intensity, bringing more stormwater through community infrastructure that is typically designed to handle less. Some storms are so intense, they bring 40% of a community’s annual rainfall in a single night. Although usually not as old as the infrastructure in the eastern part of the country, stormwater systems in the west are also aging, requiring maintenance and improvements to ensure they can handle increased land use change and water volume. In water-scarce areas, infrastructure must prevent stormwater from overflowing into and contaminating limited freshwater supplies, which can be difficult when systems are strained from increased storm events.

The western US additionally faces challenges resulting from land use changes. Like other parts of the US, many communities in these states are experiencing property development that is increasing the amount of impervious surfaces, contributing to more runoff as rainfall also rises. Some of these metropolitan areas are among the fastest growing in the country, including communities in Arizona, Idaho, Utah, and Nevada. This not only requires enhancements to stormwater infrastructure to boost its resilience to increased runoff, but also for supporting a growing population with enough clean freshwater. As is the case with other municipalities across the US, geospatial data is widely being adopted throughout western states as a source of truth for stormwater management, and AI-based mapping is greatly improving the accuracy and freshness of information available to decision-makers.

See how Ecopia’s impervious surface data is being used for stormwater management in Billings, Montana.

AI-powered impervious surface & land cover mapping

Although these regions of the US have diverse climates with unique stormwater management priorities, one thing they all have in common is the need for comprehensive, accurate, and up-to-date geospatial data. The specific features mapped and analyzed for stormwater management may differ by municipality or region, with some requiring only impervious surface data to accomplish their goals and others needing full land cover, but what stormwater professionals from all regions can agree on is the need for this data to be reflective of current land use conditions.

Traditional geospatial data creation methods involve manually tracing or digitizing individual features from satellite or aerial imagery. Doing this for each building, road segment, driveway, and other relevant land cover features across a large-scale area such as a municipality is extremely resource-intensive and time-consuming, typically taking about 12-18 months. By this time, more land use change has usually occurred, rendering the data stale and inaccurate. 

While some automated programs have been created to streamline this process, the data they produce is usually not as accurate as that manually digitized by GIS professionals. Until the last decade or so, there has not been a reliable way for stormwater professionals to source land cover data quickly and cost-effectively without sacrificing accuracy. AI-based mapping has changed that dramatically.

Advancements in AI-powered mapping have eliminated the need for manual digitization, producing high-precision geospatial data across an entire municipality in just a matter of weeks. This GIS-professional level of feature extraction is achieved at just a fraction of the cost of manual digitization, whether performed in-house or by third-party contractors. The result? Municipalities now have an accessible source of accurate and up-to-date land cover information to use in their stormwater management analytics. 

To learn more about how Ecopia can help you scale your own impervious surface or land cover data creation for stormwater management, get in touch with our team.