HEC-RAS River Channel Calibration

I need my current river model in HEC-RAS refined so it reliably supports flood management decisions. All geometric files, cross-sections, hydrologic boundary conditions, survey points, and historical high-water marks are already organised and ready for import, so you will be working with a complete and detailed data set rather than starting from scratch. The assignment is to adjust roughness coefficients, bank stations, ineffective flow areas, and any other relevant parameters until the simulated water-surface elevations match observed events within an acceptable tolerance. Once the model is behaving consistently across a range of flows, generate clear channel and floodplain delineations that I can overlay in GIS for downstream engineering and permitting work. Flood maps or velocity grids could be produced later, but for now the focus is strictly on accurate delineation of the active channel and its inundation extents. Deliverables • Calibrated HEC-RAS project files (geometry, plan, and supporting data) • Shapefiles or geodatabases detailing the final channel centreline, banks, and full floodplain outline • A brief memo (PDF) summarising calibration steps, Manning’s n adjustments, statistical fit, and any assumptions The work is considered complete when the calibrated model reproduces known flood stages within ±0.1 m at all gauged locations and the exported GIS layers align with field-verified breaklines. Feel free to suggest any additional verification checks or sensitivity runs you believe would strengthen confidence in the results.

Projektin tunnus (ID): 40294868