In 2005, approximately 10,300 Mgal/d (million gallons per day) of water was withdrawn from ground-water and surface-water sources in Louisiana. Total ground-water withdrawals were about 1,600 Mgal/d, and total surface-water withdrawals were about 8,700 Mgal/d. From 2000 to 2005, ground-water withdrawals in Louisiana decreased by 3.7 percent, and surface-water withdrawals were unchanged. Total water withdrawals in Louisiana decreased by less than 1.0 percent from 2000 to 2005.

Water withdrawal totals in Mgal/d in 2005 for various categories of use were as follows: public supply—720, industry—3,100, power generation—5, 200, rural domestic—44, livestock—8.0, rice irrigation—790, general irrigation—200, and aquaculture—270. From 2000 to 2005, changes in withdrawals, in percent, for the categories of use were as follows: public supply decreased by 5.1, industry increased by 16, power generation decreased by 7.7, rural domestic increased by 6.0, livestock decreased by 58, rice irrigation decreased by 11, general irrigation increased by 52, and aquaculture increased by 11.

Forty-two percent (about 660 Mgal/d) of all ground water withdrawn was from the Chicot aquifer system, and 26 percent (about 400  Mgal/d) was withdrawn from the Mississippi River alluvial aquifer. Since  2000, withdrawals from the Chicot aquifer system de creased by 17 percent, and withdrawals from the  Mississippi River alluvial aquifer increased by 14 pe rcent. About 76 percent (6 ,700 Mgal/d) of all surface  water withdrawn was from the Mississippi River mainst em. This value represents a 7.6 percent increase in  withdrawals from 2000 to 2005.

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