What is RAS-Flood
RAS-Flood is an assembly of three complementary software utilities which map and assess solutions to fluvial flooding by virtual case study
- Advanced GIS feature creation from Lidar to describe the catchment digitally (Globalmapper is hard to beat)
- Logical pragmatic stream Bathymetry to 1M grid from lidar point-clouds developed in stage 1 (Atrepo point-smoothing methodology)
- 2D Mesh creation and flow computation (HECRAS 2D courtesy USACE)
How long will it take to produce indicative hydrographs from catchment rainfall for comparison of alternative intervention and landuse measures?
Allow a day per 10 sq km for stage 1 (2.5 GHz x 8GB hardware) and 15 minutes per stream for stage 2. Mesh creation within the perimeter with breaklines from stage 1 is automated and takes only a few minutes. However allow an hour or so to check over such geometry manually.
Then, with geometric data saved and (initially, say) 24 hour rainfall, terrain & bathymetry loaded, the testing of an ‘Unsteady-Flow’ plan to yield indicative hydrographs can be set to take less than an hour (per 100 sq km). A cloud server running the flow analysis code is available on request (email firstname.lastname@example.org)
Will catchment flood alleviation measures be considered by policy-makers as providing ‘public good’ and thereby eligible for ‘public funds’ ?
Hard to say, but there is talk of 50p per cubic metre of ‘blue-green’ extreme event flood water storage.