1. Spring Flood of 2010 in Nashville, TN
A Discussion of Hydraulic Simulation Tools
Patrick Dobbs, EIT, CFM
AMEC Earth and Environmental
3800 Ezell Road, Suite 100
Nashville, TN 37211

2. Abstract
Today’s available hydraulic simulation tools allow for accurate analysis of major flood events with limited time investment. As a demonstration and case study, this presentation will analyze the weekend of May 1, 2010, when middle Tennessee experienced a record setting rainfall event, over 13 inches in 48 hours. The presentation will primarily highlight HEC-RAS model results through comparison of flood observations to effective flood maps. According to the National Weather Service, the Cumberland River reached a historic crest of feet. The Cumberland River had not crested above 50 feet since 1929, which predates the construction of the Old Hickory Lock and Dam, just upstream of Nashville, which is used to detain flood waters. The extent of the HEC-RAS model is a reach of the Cumberland River from Clarksville Pike, upstream to the Old Hickory Lock and Dam. Model outputs will be presented and compared to data from the flood event. Flood locations of interest will be discussed during the presentation; examples include the confluence with the Stones River, Opryland, Riverfront Park, and Metrocenter. Additional discussion will be devoted to collection of data and modeling techniques. The study will review and include data from the USGS, NOAA, TDOT, USACE, and FEMA.

3. Data Sources for Hydraulic Modeling
USGS
National Hydrography Dataset
Stream Lines
The National Map Seamless Server
Ground Surface Data
USDA
Geospatial Data Gateway
Aerial Imagery

4. Tools for Hydraulic Modeling
ArcMap
Geospatial Analysis Program
Geo-RAS
Geospatial Tool for Creating HEC-RAS Inputs
AFG
HEC-RAS
Hydraulic Modeling Software

5. Detailed Studies Approximate Studies Ground Surface Data
Study Differences
Detailed Studies
Approximate Studies
Ground Surface Data
LiDAR
Survey
Models Structures
Map Results
100yr Floodplain
500yr Floodplain
Base Flood Elevations
Lettered Cross Sections
Floodway
Ground Surface Data
USGS 10m DEM
No Structure Data
Map Results
100yr Floodplain