Case Study

Flood Improvement And LID Modeling Using XP‐SWMM

Source: Innovyze

By Andrew Juan, Dr. Nick Fang, and Dr. Philip Bedient, Rice University

Rice University is located within the Harris Gully watershed, which covers a drainage area of approximately 5 square miles, consisting mostly of fully‐developed residential and light commercial land use. The area is also home to Hermann Park and Texas Medical Center, the largest medical center in the world. A number of severe storms have impacted the Harris Gully watershed, the most notable of which being Tropical Storm Allison in 2001. TS Allison caused severe flooding problems throughout the entire watershed, resulting in roughly $5 billion in damages. Inundation was especially severe at the downstream portions of Harris Gully, where Rice University and the Texas Medical Center are located.

First developed in 1971, the EPA’s Storm Water Management Model (SWMM) has been widely used in urban areas for planning, analysis, and design related to stormwater runoff, combined sewers, sanitary sewers, and other drainage systems. XPSWMM, published by XP Solutions Inc., uses the EPA SWMM model as the primary runoff hydrograph simulator for runoff quantity and quality. The major advantage of XPSWMM over other software packages is its ability to combine a 1D river hydraulic model with a 2D rainfall‐runoff model to generate floodplain maps. In addition, XPSWMM is approved by FEMA for the hydrologic and hydraulic applications detailed in this study.

Image credit: "Flooding In FinchField, IA," © 2008 U.S. Geological Survey, used under an Attribution-NonCommercial-ShareAlike 2.0 Generic license: