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HMS-PrePro A GIS Preprocessor for Extracting Geospatial Data and Preparing HEC-HMS Hydrologic Models Cynthia V. Castro February 10, 2016
HMS-PreProA GIS Preprocessor for Extracting Geospatial Dataand Preparing HEC-HMS Hydrologic Models
Cynthia V. CastroFebruary 10, 2016
Manual HEC-HMS Model Input
Complex,Time-consuming,Expensive!
Hydrologic Modeling GIS Preprocessors
CRWR Pre-Pro(Olivera, 1998)
WRAP Hydro(Gopalan, 2003)
AGWA(EPA/USDA, 2002)
HEC-GeoHMS(USACE, 2003)
BASINS(EPA, 2001)
Over 50 User-Steps Required (Errors)Manual Data Processing
HEC Geo-HMS
Preprocessing Project Setup Obtain Data ArcHydro FDR, FAC Basin Processing Batch Points Calculate Slope Hand Select Outlets Longest Flowpath Basin Centroid
CN Grid Precipitation Grid Name Objects Convert Units Select HMS Process TR55 Parameters
Hand-draw points Muskingum-Cunge
User-input parameters Kinematic Wave
User-input parameters
Trending toward “Data as a Service”Providers host large datasets on remote servers and provide standardized methods to search and download specific sets of interest.
Allows data to be gathered automatically as part of a larger workflow.Industry-wide interoperability.
Improved access to geospatial information.
COH GIMS
USGS National Map Viewer 1:24K USGS Grids > 50,000 in U.S.
Accurate runoff estimates depend on theaccuracy of the data provided!
USGS NED DEM (3m, 10m, 30m, LiDAR) NLCD Land Use/Impervious USDA SSURGO Soils (HSG) NHDPlus v2.1 National Hydrography Dataset
Database Development
NHDPlus V2.1 Living Atlas
Geodatabase Output
GIS Preprocessor Toolbox
Database Development
Data Processing
Terrain Preparation
Watershed Delineation
Parameterization
Model Pre-Processing
All data processing options are included in one toolbox window.
HEC-HMSMethodology
Canopy Method SCS Curve Number Green & Ampt SCS Unit Hydrograph Clark Unit Hydrograph Snyder Unit HydrographMuskingum RoutingMuskingum-Cunge Routing
Output: .BASIN File
A text file serving as the HEC-HMS input that summarizes hydrologicelements, basin attributes, and connectivity within the model.
HEC-HMS Model
SCS Curve Number Method
(USDA, 1986)
SCS Curve Number
𝐶𝐶𝐶𝐶 =∑𝐶𝐶𝐶𝐶𝑖𝑖𝐴𝐴𝑖𝑖∑𝐴𝐴𝑖𝑖
1 – Lookup Table2 – Reclassify Land Use3 – Union Soils/LU4 – Individual CN5 – Composite CN
Example:Onion Creek
Onion Creek – FloodPro, austintexas.gov
FEMA Effective Subbasins
> 400 subbasins
Geodata
HUC-12
110 NHDPlusSubwatersheds
HEC GeoHMS
FEMA Effective Model 2008
SCS Curve NumberSnyder Unit HydrographModified Puls + Muskingum-Cunge
HEC GeoHMS
HMS PrePro
SCS Curve NumberSnyder Unit HydrographMuskingum-Cunge
FEMA Effective
Qp (cfs) V (in)
FEMA 101,929 6.88
HEC GeoHMS 99,788 6.77
HMS-PrePro 99,871 6.76
HMS-PreProHEC-GeoHMSFEMA
Conclusion
Data Services may be used for hydrologic modeling. Seamless data Authoritative Limited manual processing
NHDPlus subbasins and reaches provide a national framework consistent with HUC basins.HMS-PrePro may be used to initialize hydrologic
models in NHD format.
Thank you!
Questions?
