HEC-2: Flood Plain Analysis
VERSION/DATE: 4.6.2 5/91
OPERATING SYSTEM: DOS
Also See HydroPro for Windows by Dodson (Part of the ProHEC-CD package)
DOCUMENTATION (380 Pages):
HEC-2: Water Surface Profiles User's Manual September 1990 Revised: February 1991 Hydrologic Engineering Center US Army Corps of Engineers
Computing Water Surface Profiles with HEC-2 on a Personal Computer TD-#26, 1992 Hydrologic Engineering Center US Army Corps of Engineers
ADDITIONAL DOCUMENTATION (not included with this CD):
"Hands-On" HEC-2 (Tutorial and Reference Guide) by Dodson & Associates, Inc. Copyright 1987-1994 (see ProHEC-CD for more information)
Program requires 640k memory (521K free) and a hard disk. A math coprocessor is also highly recommended.
The program is intended for calculating water surface profiles for steady gradually varied flow in natural or man-made channels. Both subcritical and supercritical flow profiles can be calculated. The effects of various obstructions such as bridges, culverts, weirs, and structures in the floodplain may be considered in the computations. The computational procedure is based on the solution of the one-dimensional energy equation with energy loss due to friction evaluated with Manning's equation. The computational procedure is generally known as the standard step method. The program is also designed for application in floodplain management and flood insurance studies to evaluate floodway encroachments. Also, capabilities are available for assessing the effects of channel improvements and levees on water surface profiles. Input and output may be either English or metric units.
A data edit program (EDIT2) checks the data records for various input errors. An interactive summary printout program (SUMPO) and graphics program (PLOT2) are available for MS DOS computers. An input edit program (COED) is available with an HEC-2 input help file. All the supplementary programs are provided in the HEC-2 PC package.
PROGRAM DEVELOPMENT HISTORY
Computer program HEC-2, Water Surface Profiles, originated from a step- backwater program written in WIZ (a version of BASIC) by Bill S. Eichert in 1964. This early version was developed on a GE 225 system at the Corps of Engineers Tulsa District office. in 1966 the first FORTRAN version of HEC-2 was released by the Hydrologic Engineering Center (HEC) under the name "Backwater Any Cross Section."
As the name implied, Backwater Any Cross Section (unlike the other early backwater programs) was capable of computing water surface profiles in channels with irregularly shaped cross sections. This program represented a significant step in the development of modern computational techniques for hydraulic analysis.
The program was revised and expanded and in 1968 was released as HEC-2, Water Surface Profiles, the second in a series of generalized computer programs issued by the HEC. Since the first release of HEC-2 in 1968 the addition of new features and improvements have prompted the release of new versions in 1971, 1976 and 1988.
In 1984 Alfredo Montalvo adapted HEC-2 to the microcomputer (PC) environment. The PC release of HEC-2 has been accompanied by the introduction of PC based support programs, SUMPO and PLOT2.
The February 1991 release of HEC-2 (Version 4.6.0) includes the capability to simulate culvert hydraulics using the Federal Highway Administration's (FHWA) culvert procedures. The FHWA procedures were added to HEC-2 by Roy Dodson, Dodson & Associates, Houston, TX.