nishnabotna / platte edu umbrella mitigation bank site 1 -
Castile Creek
Buchanan County, Missouri
@ Lisa Owens
Situated at the confluence of the Platte River and Castile Creek, this 291-acre restoration site is the first wetland and stream mitigation bank in northwest Missouri.
Not only is this Swallowtail’s largest mitigation project to date, this site has provided significant floodplain management and environmental gain. In addition to restoring this vast property from agricultural fields to native wetland, riparian, and prairie habitats, the onsite levees were breached, which re-established floodplain connectivity to 170 acres of land along the flood-prone Platte River. In all, this mitigation site legally protects one or both sides of almost 2.5 miles of streams, with 1.9 of those miles being along the Platte River and Castile Creek. This legal protection, along with the expansion of previously narrow riparian corridors to a width of 600 feet, was especially valuable because Castile Creek receives the highest level of priority from regulatory agencies due to its status as a designated fish spawning habitat. In addition, the property had previously been identified by the Missouri Department of Conservation as a high priority acquisition area.
Prior to restoration, this site consisted of large expanses of artificially drained, flat farm fields. Most of these fields were protected by levees, which reduced the connectivity between the Platte River and Castile Creek and their floodplain and, therefore, worsened flooding elsewhere. Additionally, several ephemeral streams had been eradicated or highly modified by agricultural earthwork.
These impairments were addressed through the following activities:
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Restoring floodplain connectivity through multiple levee breaches along the Platte River and Castile Creek
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Restoring or enhancing 119 acres of riparian buffers
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Restoring 84 acres of herbaceous wetlands and 53 acres of forested wetlands
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Establishing or preserving almost 19 acres of wetland buffers and adjacent uplands
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Restoring normal sinuosity and channel dimensions to a previously eradicated ephemeral stream
Mitigation activities began in early 2018 and the site has flooded numerous times since then through the levee breaches.
