Where does stormwater go? Colorado Stormwater Center provides research and training on resilient infrastructure

Colorado Stormwater Center director Tyler Dell explains a stormwater feature to a seminar group on the Colorado State University Fort Collins campus, September 2019.

On a bright, sunny day in Fort Collins early last fall, Tyler Dell, director of the Colorado Stormwater Center, led a group of seminar attendees across campus.

The 90-degree day sent shadows of trees playing on the gardens near the edges of the buildings. Squirrels ran down the bank and into the tall cattails. Attendees stopped to consider the paved bricks that make up much of the Center Avenue Mall near the Clark Building.

Despite the heat, the wildlife, and everything they walked by, the group was only concerned with the one thing that was not visible.

Stormwater.

“A lot of people just think that it rains, or snows, and that water just goes into the ground,” said Dell. “They don’t realize that there’s a whole system underneath them.”

An elaborate network

As he walked, Dell explained to his seminar of Colorado State University facilities managers and environmental specialists how to design and operate various aspects of stormwater management, including initial stormwater mitigation development and yearly maintenance. He regularly gives training to local developers, municipal and county employees from across the state, and the public.

Mazdak Arabi, director of the center’s parent organization, One Water Solutions Institute at Colorado State University, said that both research and training are part of the organization’s mission.

“The Stormwater Center increasingly trains professionals across the state, to make our communities more livable by better managing water systems,” said Arabi.

Training that Dell gives expands beyond the typical storm drains and grates that most people are familiar with. There is a lot more complexity involved in stormwater mitigation, and often those elements are right in front of us.

Colorado Stormwater Center director Tyler Dell showing the stormwater features near the CSU Health and Medical Center, September 2019.
Colorado Stormwater Center director Tyler Dell showing the stormwater features near the CSU Health and Medical Center, September 2019.

Stormwater mitigation everywhere

Gardens, like the ones near many buildings on campus, are rain gardens, designed to collect water and let it soak into the ground instead of flowing into the storm sewer. The tall cattails and other plants fill a depression surrounding a grate, slowing the water down and filtering it before it enters the storm drain.

Even the bricks on Center Avenue help stormwater mitigation. They aren’t just standard red bricks or concrete. They are specifically developed to absorb a certain amount of water that falls on them.

Dell has a big job — stormwater mitigation is a part of the state’s infrastructure that is not well understood by the public. People take stormwater for granted until there is a massive storm, like the September 2013 flooding across the Front Range.

The center’s seminars and planning tools help communities plan for both large flooding events as well as normal, seasonal moisture. Those trainings are based on the other half of their mission, which is extensive research into stormwater mitigation in Colorado.

Challenges of long-term research

Stormwater research is a developing field, with projects that often take years to determine the effectiveness of a mitigation plan.

“For me to get good, drawn-out research, it would be my whole career,” said Dell. “The answers we get from a study might not even come in for another two decades.”

Infrastructure and stormwater research is finally catching up with projects from the last two to three decades. Dell’s research is finding the differences in which structures have failed over time, compared with those that are more resilient.

Stormwater researchers can use that information, combined with adapted techniques from other areas of the country, to apply research to new infrastructure projects and consultations in similar semi-arid areas to Colorado. The center can then work with infrastructure owners to track progress and monitor their maintenance for future comparisons.

Climate change and the past, present, and future

Comparisons with past efforts are already problematic, as many municipalities do not track their stormwater mitigation efforts. Even if Dell finds benchmark data from the last 100 years for a specific location, the pace of climate change might make that data irrelevant in planning for resilient infrastructure.

“We used to think with these long, continuous records that we could actually predict the 100-year storm, and were really helpful,” said Dell. “But are they? If climate’s changing, what was happening in the 1920s doesn’t matter any more.”

Dell says that it comes down to engineering and design. Plans based on what happened in the past are not as relevant compared to what is happening now. Some municipalities have started to include current and future climate projections in their stormwater planning.

Engineers now research and design infrastructure with more modular capabilities in mind. Modular elements are structures which can be added or removed easily, depending on the adaptations needed for an area. That makes it more manageable to adapt stormwater mitigation efforts for climate change.

Now versus later: maintenance

As Dell and the seminar group finished the tour of stormwater mitigation, he explained to the group that maintenance, modularity, and attention to the area over time mean the difference between successful or failed mitigation efforts.

He compares mitigation to how someone treats their car. You can choose to never change the oil in your car, and keep it running until it dies at 100,000 miles. Then you just buy a new one and move on.

Dell prefers being proactive. Change your oil every 5,000 miles, and care for the vehicle so it lasts a long time. You may eventually need a new vehicle, but the effort provides consistency and long term use.

The same is true of stormwater mitigation efforts. A municipality might choose to spend hundreds of thousands of dollars every time infrastructure requires major rehabilitation, or a few thousand annually to keep things working. Depending on the politics and economy at the time, smaller fees and gradual adjustments might be easier to plan for within a municipal budget than a large, expensive project.

Whether it is a rain garden, a simple grate, or even permeable bricks, stormwater mitigation is important to every area of the state. Right down to the places we live.

“You can’t walk down a city block without seeing some infrastructure that’s there purely for stormwater,” Dell said. “It’s the whole reason someone’s house is the highest point of their yard.”