Louisiana Coastal Area, Louisiana. Notice of Study Findings. Water Supply.

摘要

This report presents the results of an initial evaluation to determine the advisability of improvements or modifications of existing improvements in coastal areas of Louisiana in the interest of water supply. The study area includes all lands subject to tidal overflow in 20 coastal parishes. In 1980, the population of the area was about 2,077,934 and is projected to increase to 3.045,000 by the year 2040. Water supply withdrawals in the study area were nearly 11 billion gallons/day in 1980, 87% was from surface water sources. Major surface water sources, besides the Mississippi River, are the Gulf Intracoastal Waterway, the Mermentau River, the Calcasieu River, and Bayou Lafourche. Some 39 square miles of land are lost each year to subsidence and erosion, and that rate is projected to increase. As the marshlands are converted to open water, the opportunity for saltwater intrusion are greatly increased. Current water supplies are frequently subject to saltwater intrusion and a number of coastal communities are seeking alternative sources of fresh water. Six problem areas were identified and 27 alternative plans were developed. From a preliminary analysis of cost and impacts, 12 plans were recommended for further study. The total study cost for the five studies, including the initial evaluation cost, is $3,800,000. The first study would be complete by the end of fiscal year 1987. (edc)