Getting Started & Project Workflow

GeoHECHMS Overview & Comparisons

How is GeoHECHMS different than HEC-HMS?

Common Workflows

Common HEC-HMS Workflows

Importing / Exporting Models

Exporting a HEC-HMS Model to HydroCAD
Importing a HydroCAD Project
Importing a HEC-HMS Model
Importing a HEC-1 Model in HEC-HMS
Exporting Your Project to HEC-HMS

Scenarios & Plans

Current Plan Analysis (HEC-HMS)
Multiple Plan Analysis (HEC-HMS)
Scenario Summary (HEC-HMS)
Delete Scenarios (HEC-HMS)
Duplicate Current Scenario (HEC-HMS)
Understanding HEC-HMS Scenarios
Global Copy Command

Display & Element Properties

HEC-HMS Element Display Properties

Watershed & Subbasin Modeling

Watershed Delineation

Delineate Catch Basins Command
Subbasin Delineation
Delineate Subbasins Command

Subbasin Drawing & Assignment

Georeferencing Subbasins

Subbasin Editing

Subbasin Table Edit Command
Reshape Subbasins Command
Split Subbasins Command
Merge Subbasins Command

Subbasin Properties

Subbasin Data Command
Hydrologic Properties

Subbasin Computations

Recompute Properties Command
Compute Reach Parameters Command
Compute Subbasin Areas Command
Compute % Impervious Command

Curve Numbers & Land Use

Curve Numbers for Urban Impervious Areas
Automated Curve Number Computation

Compute Slopes Command

Loss/Runoff Methods

Canopy Methods

Subbasin Data - Selecting a Canopy Method

Surface Storage Methods

Subbasin Data – Selecting a Surface Storage Method

Infiltration / Loss Methods

Subbasin Data – Selecting an Infiltration Method
Compute Green Ampt Command

Baseflow Methods

Subbasin Data – Selecting a Baseflow Method

Initial Abstraction

Double Counting Impervious Areas

Double Counting Impervious Areas

Transform Methods (Unit Hydrograph)

Runoff Method Selection

Subbasin Data - Selecting a Runoff Method

SCS Unit Hydrograph & Peaking Factor

SCS Hydrograph Peaking Factor

Time of Concentration (TOC)

Subbasin TOC Data - Selecting FAA TOC Method
Subbasin TOC Data Command
Subbasin TOC Data - Selecting SCS Watershed Lag Method
Subbasin TOC Data Table Edit Command

Reach Routing

Reach Drawing & Assignment

Georeferencing Reaches
Merge Reaches Command
Automated Draw Reaches Command
Reverse Reaches Command
Draw and Assign Reaches Command

Reach Properties & Editing

Reach Table Edit Command
Reach Data Command
Renumber Interconnected Reaches Command

Routing Method Selection

Reach Data - Selecting a Routing Method

Loss/Gain Methods

Reach Data - Selecting a Loss/Gain Method

Connect Downstream

Connect Downstream Command

Hydrologic Elements

Junctions

Junction Data Command
Renumber Interconnected Junctions Command
Georeference Junctions Command
Draw and Assign Junctions Command

Sources

Source Data Command
Georeferencing Sources
Draw and Assign Sources Command

Sinks

Sink Data Command
Georeferencing Sinks
Draw and Assign Sinks Command

Diversions

Diversion Data - Selecting a Diversion Method
Renumber Interconnected Diversions Command
Georeferencing Diversions
Draw and Assign Diversions Command

Reservoirs / Storage Areas

Storage Area Data Command (HEC-HMS)
Defining Spillways for HEC-HMS Storage Areas
Defining Dam Crest Geometry for HEC-HMS Storage Areas
Defining Dam Breach for HEC-HMS Storage Areas
Defining Culverts for HEC-HMS Storage Areas
Defining Outflow Routing for HEC-HMS Storage Areas
Defining HEC-HMS Storage Areas
Assigning HEC-HMS Storage Areas
Drawing HEC-HMS Storage Areas

Meteorology & Precipitation

Rain Gages

Rain Gage Data Command (GeoHECHMS)
Precipitation Type - Rain Gage

Precipitation Methods

Precipitation Type - Rainfall Distribution
Precipitation Type - Standard Project Storm
Precipitation Type - Specified Hyetograph
Precipitation Type - SCS Storm
Precipitation Type - Inverse Distance Weighted
Precipitation Type - HMR52 Storm
Precipitation Type - Frequency Storm

Rainfall Lookup & Critical Storm

Compute Critical Storm Command
Lookup Rainfall Command (GeoHECHMS)

Meteorology Data

Meteorology Data Command
HEC-HMS Model Components
HEC-HMS Hydrology Methods

Cross Sections (HEC-HMS context)

Creation & Drawing

Draw and Assign Cross Sections Command (HEC-HMS)
Automated Draw Cross Sections Command (HEC-HMS)
HEC-HMS Cross Sections

Editing & Extraction

Extract Cross Section Geometry Command (HEC-HMS)

Georeferencing & Renumbering

Georeference Cross Sections Command (HEC-HMS)

Computational Analysis & Output

Computational Options

Computational Options Command

Control Specifications

Control Specifications Command

Plot Hydrographs

Plot Hydrographs Command

DSS Data

Data Storage Descriptors in HEC-DSS
DSS Data File & Path

Result Summary

Result Summary Command

Reports

Generate Report Command
Generate Report - Editing Project Map

Integration & Imports

Linking to HEC-RAS

Linking Flow Data from HEC-HMS to RAS

Flow Paths

Upstream Flow Paths Command
Draw and Assign Flow Paths Command

Manning's Data & Roughness

Manning's Editing

Assign Manning's Data (HEC-HMS)
Editing Manning’s Data

Troubleshooting & Editing

Restricted Web Services

Troubleshooting Restricted Web Services

Global Editing

Global Edit Command
Global Find Command
Global Editing Command

Elevation Assignment

Assign Elevations Command

Other

Pipe Network

Export Pipe Network Command
Import Pipe Network Command

Conflate Point Data

Conflate Point Data Command (HEC-HMS)

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Home › GeoHECHMS › Loss/Runoff Methods › Initial Abstraction

Initial Abstraction

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