Evan Pratt

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Joined

March, 2022

Recent Activity

Commented on Resilient Washtenaw 5 months, 3 weeks ago
It will be important to complement Carbon Neutrality goals with Climate Adaptation/Mitigation strategies. Some of those strategies will require significant investment in the built environment. Many readers may be aware that warmer air can absorb more moisture. So this is why increasing temperature graphs for the past 20-30 years are the same shape as graphs showing increases in peak rainfall. Many urbanized areas already had a need for improvements to reduce the severity and frequency of flooding from the documented and anticipated increase in rainfall intensities. Periodical statistical analyses of actual rainfall at hundreds of gauges across the state and regions have shown that from the 1960s to 2010s Washtenaw County saw a nearly 40% increase in peak rainfall, for storms with either a 1% or 10% chance of occurring in any year. Many folks say "100-year storm" and "10-year storm" respectively for these events. The majority of pipes and basins in urbanized parts of the County were built in that time period. So because it is true that it has been raining harder, AND many (if not most) systems were not designed to handle current rainfall, AND many more (if not most) systems will not be able to handle future 1% and 10% storms, there will need to be substantial investment in "gray" stormwater infrastructure, such as existing storage facilities. Future rainfall intensities have been conservatively forecast (in an MDOT/SEMCOG [very technical] study) to be ~70% more by end of century. Study here: https://semcog.org/plans-for-the-region/environment/climate-resilience
Commented on Resilient Washtenaw 5 months, 3 weeks ago
One thing that is not obvious is that reduced water consumption would be a beneficial goal. While many agencies have invested in reduction of energy consumption with their water infrastructure, drinking water and wastewater treatment (and any pumping across the system) are typically the largest energy demand for any community/agency that provides those services. This can be 30 to 40% of the energy costs. (for the government agency as a whole) So reduced water use = reduced energy use. Second idea: On a related note, eliminating bottled water to the extent possible would be a huge benefit. HRWC provided data years ago that it takes 3x the energy to make the plastic bottle than to provide the water. And the Absopure facility in Plymouth Township just bottles Detroit/Great Lakes Authority water straight out of the pipe. A long-term promotion of this and other benefits of tap water (much more stringent sampling requirements than bottled) would be beneficial due to lingering effects of lead concerns along with other emerging contaminants. A lot more people do not trust their municipal water than even 10 years ago.
Commented on Resilient Washtenaw 5 months, 3 weeks ago
Green Infrastructure (GI) is a great amenity to stormwater systems. It is highly dependent on soil type and many other site considerations. It would be good to find funding to create a map of (feasible) opportunities in urban areas - site factors make GI more challenging to implement than most folks realize. My office is in talks with City of AA to facilitate a bus tour to see existing GI and discuss challenges. GI has great co-benefits including water quality, habitat, and aesthetics (to some folks anyhow).

The scale of increasing storms and resulting volumes of water overwhelm much GI, with the exception of some 300+ newer developments that have met County infiltration requirements implemented in 2014.

But since the urbanized areas are most vulnerable, the main contributors, and have a majority of land area developed with no stormwater storage/detention, significant investment in 'gray infrastructure' is also needed, such as new and retrofitted storage facilities.
Supported a comment by Teresa G on Resilient Washtenaw 5 months, 3 weeks ago
Teresa G
Enforcement tools and/or other means to encourage care of storm water facilities on private land (drains and retention basins) are also key related to flooding issues.
Supported a comment by Andrew DeLeeuw on Resilient Washtenaw 5 months, 3 weeks ago
Andrew DeLeeuw
There was significant flooding near the Huron River last summer when we got all that rain in June. I'd like to see more options to reduce flooding using plants and green spaces.
Supported a comment by Theresa Tupacz on Resilient Washtenaw 5 months, 3 weeks ago
Theresa Tupacz
As mitigation plans are developed for Huron River flooding, with plants and green spaces, sharing this information with county wide homeowner associations (HOAs) will assist neighborhoods that are experiencing worsening water drainage problems.