Developing a screening tool to identify potential floodplain restoration sites
I'm wondering if it would be possible to use GIS to develop a screening level tool to identify floodplains that are currently cut off from their river channels for most flood flows (say less than a 0.02 exceedance probability/50yr recurrence interval).
The idea would be to target floodplain restoration sites. If these areas are targeted then potentially several benefits could be developed. As a restoration site, an aquifer could be recharged, sidewater habitat is created, riparian seeds could be dispersed, and if enough overbank storage occurs, downstream water surface elevations could be lowered, thereby lowering flood damages.
A dam removal project often takes several years, and a floodplain restoration project wouldn't be any different. There would be financing questions, stakeholder engagement, permitting, proponents and opponents weighing in, and environmental review to name a few of the steps. But the process has to start somewhere, and a screening tool that is literally cherry picking for the best sites, the most feasible sites, would be the first step. Just as there have been many dams targeted for removal that for one reason or another don't get removed, the same fate could happen for identified floodplains. Nevertheless, if a screening level tool was developed, it seems like this would increase the chances of project success. It would be a starting point to undertake a feasibility study.
If anyone has thought on how such a screening level tool could be developed using GIS, elevation data, hydrologic routing models, landuse data, population density data and some other datasets, I'd be all ears.