Roads and Bridges have evolved over time from their roots in footpaths and log bridges into modern transportation routes capable of carrying vast amounts of goods and services around the nation. Today's roads and bridges provide the physical connections that are the taproot of our society and the safe operation of these roads and bridges is vital to our nation's prosperity. Approximately 86 % of all bridges in the United States are built over streams.
What is hydraulic design?
According to Webster's Dictionary hydraulic means operated, moved, or effected by the means of water. In a transportation context this refers to drainage structures such as bridges or culverts. The purpose of hydraulic design is to ensure structures are of sufficient size that natural flooding is not worsened and to ensure that the structure can withstand the design flood and remain traversable. This is required in order to protect the property and residents upstream and downstream of a highway structure and any motorists who use the roadway. Hydraulic designers also must account for scour. Scour refers to the tendency of soil in a streambed to be washed away by flowing floodwaters.
Earth is a world of water. Roughly three quarters of this planet is covered by water. The interaction between the sun and the water is the force behind life on this planet. Rain, falling one drop at a time, can produce tragic results. Since 1990, nearly all presidential declared disasters in Tennessee involved precipitation of some kind. Most have involved flood damages.
In the design of bridges and roads, one main thing to remember is that STREAMS and
RAINFALL are DYNAMIC. No two stream crossings are exactly alike and no two floods are
Responsibilities: Responsibilities of the Hydraulic Design Section.
History: A brief history of hydraulic design in TDOT.
Downloads (Adobe PDF format): (to download right click the link and choose save target as)
Hydraulic Design Summary form (English) as required on all hydraulic designs.
CADD submittal form (English) checklist for hydraulic preliminary.
Sample project file (8.57 MB, May take a long time to download.)
Links: Some links of interest. Includes links to environmental regulatory agencies.