Riparian Habitat Assessment and Hydromodification Mitigation
Quantifying geomorphic and hydraulic function of riparian plantings is challenging; for this reason, it has been difficult for regulators to accept it as a mitigation tool.
Through geomorphic analyses and H&H modeling W2r determined the effect of riparian vegetation on stream and floodplain functions along select streams in Washington County. In particular, analyses focused on quantifying the storage and attenuation benefits of floodplains with a rich riparian multi-story canopy vs a monoculture of invasive species (reed canary grass).
The assessment not only conveyed technical information, but also the story of stream impacts and restoration processes in a manner that was clearly understood by regulators and stakeholders. As a result, the project procedures and resulting analyses provide a framework for CWS to use riparian planting as a hydromodification mitigation tool.
Client
Columbia River Estuary Study taskforce
Keywords
Quantification of geomorphic and hydraulic function, hydromodification mitigation, vegetation function, floodplain storage and attenuation
