The Hydrologic Engineering Center (HEC) of the Army Corps of Engineers water resources program has developed widely used computer models for the analysis of watershed hydrology and open channel hydraulics. Keeping current with recent HEC software advances, Riverside Technology, inc. (RTi) has successfully applied several of these models in our water resources investigations.

HEC-RAS - River Analysis System

Working in cooperation with HEC, our software engineers have incorporated HEC-RAS and its Geographic Information System (GIS) modules into continuously operating flood inundation mapping tools. RTi has calibrated HEC-RAS inputs to re-create historical floods as well as to investigate hypothetical events. Model outputs have been used to track and predict flood inundation for bridge crossings and communities.

HEC-6 - Scour and Deposition in Rivers and Reservoirs

RTi project teams have investigated general aggradation and degradation at bridges and pipeline stream crossings using HEC-6. Total scour estimates were made by reviewing model results, in combination with localized estimates based on Federal Highway Administration techniques. Additional HEC-6 analyses to investigate channel stabilization alternatives have been conducted by RTi personnel as part of advanced scholastic programs.

HEC-1 - Flood Hydrograph Package

RTi has used HEC-1 estimates of peak flows and hydrograph volumes for selected storms to develop project design recommendations for diversion ditches, retention ponds, and spillways.

HEC-5 - Simulation of Flood Control and Conservation Systems

RTi personnel have received formal training from HEC in Davis, CA on this reservoir modeling software package. Our familiarity with HEC-5 has allowed us to use project files from outside sources when performing additional reservoir modeling, and to provide a common basis for communication in discussions of inputs/outputs between the USACE and other water management agencies.

HEC-FFA - Flood Frequency Analysis

Based on the Water Resources Council Bulletin 17B approach, this software has been used by RTi to estimate and display flood frequencies for input to dike (levee) improvement studies and associated economic evaluations overseas.

HEC-2 - Water Surface Profiles

RTi has developed recommendations for channel improvements, culverts, and drainage channels based on steady or gradually-varied flow modeling conducted with HEC-2. Combined with other software packages, RTi has used hydraulic information from HEC-2 modeling to investigate bridge scour and channel instabilities.