September is “National Preparedness Month”!
Each year, the EPA encourages and reminds us to be prepared for disasters or emergencies in our homes, businesses, and communities.
According to a National Academy of Sciences journal 2021 study, total U.S. flood damage costs approached $200 billion from 1988 through 2017—approximately $73 billion of damages due to excess precipitation over the 29-year period:
Precipitation extremes have increased in many regions of the United States, suggesting that climate change may be exacerbating the cost of flooding. However, the impact of historical precipitation change on the cost of US flood damages remains poorly quantified. Applying empirical analysis to historical precipitation and flood damages, we estimate that approximately one-third (36%) of the cost of flood damages over 1988 to 2017 is a result of historical precipitation changes. Climate models show that anthropogenic climate change has increased the probability of heavy precipitation associated with these costs. Our results provide information quantifying the costs of climate change, and suggest that lower levels of future warming would very likely reduce flooding losses relative to the current global warming trajectory.
National Academy of Sciences journal proceedings titled
“Contribution of historical precipitation change to US flood damages”-Jan 2021
“Pluvial flooding” from abstract “Pluvial flood risk and opportunities for resilience”:
https://wires.onlinelibrary.wiley.com/doi/abs/10.1002/wat2.1302
Various technologies and infrastructure strategies have been implemented to better manage stormwater in cities, but much of that infrastructure is aging. Pluvial flooding—flooding from rainfall—is an increasing issue in urban areas that disrupts trucking routes and livelihoods around the world. The study stated, “Many contemporary cities are vulnerable to pluvial flooding, and its associated risks are projected to increase as the global climate changes, urban populations grow, and existing infrastructure ages. Pluvial flood risk and opportunities for resilience.” Pluvial flooding occurs when precipitation intensity exceeds the capacity of natural and engineered drainage systems, and it is expected to increase in frequency, severity and impact through the 21st century due to the combined effects of climate change and urbanization. (see additional paper abstract link below)
PERMEABLE PAVEMENT:
Permeable pavement is a green infrastructure solution that was designed to allow rainwater through to the ground below, reducing runoff and pluvial flooding while simultaneously refilling depleted aquifers. However, the pores in permeable pavements often get clogged, reducing the rate at which water can flow through.
NEW PERMEABLE PAVEMENT CLOGGLESS PERMEABLE PAVEMENT:
Kevin Kunz and Greg Johnson, Co-Founders of AquiPor-Spokane, Washington, had a goal to create a more sustainable stormwater infrastructure with virtually cloggless permeable pavement called AquiPor: This permeable innovative hardscape pavement has pores a fraction the size of hair follicles to prevent clogging, yet it maintains the strength and durability of conventional roads, while featuring the strength and durability of traditional concrete. AquiPor pavement:
• Precast Concrete Material
• Fine ‘sandpaper feel’
• 1-micron-diameter pores—submicron porosity
• Allowed more than 25 inches of rainfall per hour to flow through its tests … more than 80% of particle matter & pollutants found in stormwater!
• Extremely small pore size is makes it unique—sub-micron-sized filter
• Manufactured easily and inexpensively
• Made less slippery than regular permeable pavement
No matter the size of the pores, they eventually clog, but, Kunz said, “The difference is, there has never been a sub-micron-sized filter made as [inexpensively] and easily as this precast concrete material. That’s an important advantage because, once the material clogs, it can be easily and cost-effectively replaced.”
In an internal study, the permeable material prevented more than 80% of particulate matter and pollutants found in stormwater from getting through. Kunz described the material as “fine sandpaper” to the touch. The goal is to reduce runoff and standing water, potentially making the permeable pavement less slippery for walkers, bikers and drivers. In an upcoming mock-up—in a full cradle-to-cradle analysis, spanning from production to end-of-life for the material—the company plans to analyze:
• Texture
• Abrasion resistance
• Emissions
• Other factors
NEW PERMEABLE PAVEMENT GREEN INFRASTRUCTURE: Potential climate change, flooding solution in cities
Shows standing water on the road,
while tan lane of permeable pavement allows water through [to ground below]
In an Environmental Protection Agency (EPA) article titled “Climate Impacts on Transportation”, increased rainfall & flooding can damage roadways, bridges & tunnels, sometimes wiping out major freight routes. It can also reduce the life expectancy of highways & interfere with road construction, which could lead to more traffic delays for truck drivers … particularly concerning in light of climate change.
“While the local impacts of climate change on annual precipitation totals remain uncertain, there is a general consensus that global climate change will result in more intense short-duration precipitation events in many regions of the world,” the study said.
NEW PERMEABLE PAVEMENT GREEN INFRASTRUCTURE GOALS & FINDINGS SO FAR:
• Filters
• Absorbs stormwater where it falls
• Reduces the distance that rainwater travels before it is absorbed mimics natural processes
• Saves money (according to the EPA)
• More cost-effective than conventional stormwater management—much cheaper to manage stormwater on a smaller scale than it is to direct larger amounts of water to overwhelmed storm drains (proven so far, Kunz said)
IF GROUND BENEATH NEW PERMEABLE PAVEMENT BECOMES OVERSATURATED:
“In practice, many types of [green infrastructure] rely primarily on the infiltration of stormwater to mitigate flooding and would be limited in their effectiveness when rainfall rates greatly exceed the maximum infiltration rates of their soils,” the 2018 study said. While the AquiPor material may be able to let upwards of 25 inches of rain per hour flow through, there’s little data indicating that soil below would be able to absorb that much water at that pace, especially during heavy, prolonged rainfall. Questions remain whether green infrastructure may provide significant economic and environmental benefits, but …
Tyler Cole, Director of Carbon Intelligence-FreightWaves, said, “It’s refreshing to see that new, innovative solutions for replacing crumbling infrastructure are electing to focus on environmental upgrades alongside functionality. The hype around electrification and reducing emissions can at times overshadow other crucial areas of impact, such as efficient and safe water systems. We need more firms like AquiPor to identify, develop and scale climate solutions.”
AquiPor Bricks of pavement drying. (Photo: AquiPor)
80-FOOT MOCK-UP OF NEW PERMEABLE PAVEMENT TO PROVIDE ADDITIONAL DATA:
AquiPor is building an 80-foot mock-up of permeable pavement at a Spilker PreCast-Spokane, Wa. Kunz said he hopes the mock-up will be finished in the fall.
• ONE HALF of mock-up will be dedicated demonstrations
• OTHER HALF will be tested over the coming years by the Washington Department of Ecology. The agency has a standard for treatment of stormwater quality that Kunz said is “stringent” and increasingly being recognized by states nationwide.
The AquiPor mock-up is designed to:
• Provide empirical data
• Answer important questions, including whether it meets the Washington Department of Ecology’s standards
• Use cement and recycled aggregates that are prevalent nationwide
• Use recycled aggregate
• Use unique cement
• Make the production-related emissions much lower than typically used road materials such as concrete or asphalt but, this will be backed by data following the mock-up. (Kunz said)
Kunz said, After the mock-up and analysis of the manufacturing process are complete, the company plans to:
Begin educating PreCast manufacturers about how to make the permeable pavement in early 2022
AquiPor’s goal is to build facilities within 500 miles of major cities where the material would be used for roads or sidewalks. Kunz said [since] the cement and recycled aggregates needed for production are prevalent nationwide, AquiPor hopes to source the materials near facilities.
Kunz said, “We have to identify the magnitude of the problem with climate change before we [breeze] through innovation into the market because this has to be done correctly the first time—then we can start full-scale!”
For helpful LINKS, please go to:
FreightWaves Online News article titled “Could permeable pavement reduce flooding in cities?”: www.freightwaves.com/news/could-permeable-pavement-reduce-flooding-in-cities
AquiPor: https://aquipor.com/
National Academy of Sciences journal Paper Abstract titled “Contribution of historical precipitation change to US flood damages”: www.pnas.org/content/118/4/e2017524118
Paper Abstract titled “Pluvial flood risk and opportunities for resilience”: https://wires.onlinelibrary.wiley.com/doi/abs/10.1002/wat2.1302
EPA article titled “Climate Impacts on Transportation”: https://19january2017snapshot.epa.gov/climate-impacts/climate-impacts-transportation_.html
AquiPor YouTube VIDEO on structure of new permeable pavement: www.youtube.com/watch?v=kOSRqu12GOk&t=42s