PROJECTS
Flooding in the Corridor
The Saw Mill Run Economic Flooding Study
To develop a rationale for change along Saw Mill Run particularly as it relates to floodplain management, land use practices, and the importance of reversing over 100 years of disinvestment in the corridor.
This study provides an economic analysis of the Saw Mill Run Boulevard corridor.
This study was financed in its entirety by a grant from the Hillman Foundation.
We would like to thank the consultant team of HDR Engineering and One Water Econ for performing the analysis. Special thanks to Project Manager Tom Batroney from HDR Engineering - Pittsburgh Office, and Janet Clements and Claire Sheridan, economists from One Water Econ.
Creating a Healthy & Economically Vibrant Stream Corridor
Floodplain Management
What it means:
Floodplains are the low-lying areas adjacent to a stream or river that naturally flood during rainstorms.
Floodplain management is a decision-making process to increase community resiliency by restoring and protecting the natural function of floodplains, ultimately reducing flood damages.
What it looks like:
When floodplains are restored to a nearly natural state, not only do they reduce severity of floods, but they can also help handle stormwater runoff and minimize nonpoint water pollution for far less money than it would take to build facilities to correct these problems.
Why it matters:
It is important to recognize that there is nothing inherently “wrong” with flooding along streams.
When streams flood, the process serves as part of the Earth’s natural water and nutrient cycles. Along every stream, even in areas sparsely inhabited by humans, streams will occasionally overtake their banks and flood. When streams flood their banks, nutrient and mineral-rich sediment is deposited onto floodplains resulting in increased soil fertility. As floodwaters recede, the sediment helps sustain diverse plant life within wetlands and riparian buffers, which in turn supports wildlife.
As such, the naturally reoccurring process of flooding onto floodplains is the cornerstone for creating a healthy stream habitat, enhancing water quality, and sustaining healthy insect, bird, fish, and animal populations.
A diagram of an ecologically functional floodplain, modified from Nutrient Retention in Ecologically Functional Floodplains: A Review.
What will we see in the future?
Under existing conditions, the annual costs of flooding are $3.4M and increase to $4.7M using future climate change rainfall estimates. Societal distress costs were determined to represent 9 to 10% of the total annual costs as shown in the pie charts below in light blue.