Abstract: Vermilion River Flood Gates: To Mitigate Lafayette (LA) Flooding

KINSLAND, GARY
Univ. of Southwestern Louisiana, Lafayette, LA

Lafayette, Louisiana, a city/parish area with population about 170,000, is situated mostly on an upland terrace in southern central Louisiana. The area is bisected by the Vermilion River which flows through an incision in the upland terrace.

As Lafayette has grown, with the consequent increases in impermeable area and in demands for drainage, the Vermilion River has served as a convenient sink for storm waters. However, more and more frequently storms are overwhelming the capacity of the river to carry away runoff. Drainage coulees rush water to the Vermilion within Lafayette resulting in a pile of water and bidirectional flow away from this pile. This pile floods several neighborhoods situated in lower areas along the river causing strong public demand that something be done.

In an ongoing study the US Army Corps of Engineers proposes to remove water from the river with diversion and pumping projects north (normally upstream) of Lafayette. This proposal would have serious adverse impacts on many square mi of wetlands and would only lower the stage within Lafayette by 2 ft for the presently defined 10 year reoccurrence interval flood stage, a flood stage which is occurring more and more frequently as Lafayette grows.

The solution presented here is to install gates on the Vermilion River between the major sources of storm inflow and the portion of Lafayette which experiences river flooding. Closing these gates would force the bulk of storm waters south away from the vulnerable parts of Lafayette. Pumps to move water from the normal upstream side of the gates up and over to the downstream side would keep river stages low in the parts of Lafayette which now experience river flooding.

Such a structure and an enforced detention ordinance are proposed as beginning steps in a comprehensive drainage plan which needs to be developed to allow future growth of Lafayette.

AAPG Search and Discovery Article #90932©1998 GCAGS/GCS-SEPM Meeting, Corpus Christi, Texas