Study region: The Mississippi Alluvial Plain (MAP) in the United States (US). Study focus: Understanding local-scale groundwater use, a critical component of the water budget, is necessary for implementing sustainable water management practices. The MAP is one of the most productive agricultural regions in the US and extracts more than 11 km3/year for irrigation activities. Consequently, groundwater-level declines in the MAP region pose a substantial challenge to water sustainability, and hence, we need reliable groundwater pumping monitoring solutions to manage this resource appropriately. New hydrological insights for the region: We incorporate remote sensing datasets and machine learning to improve an existing lookup table-based model of groundwater use previously developed by the U.S. Geological Survey (USGS). Here, we employ Distributed Random Forests, an ensemble machine learning algorithm to predict annual and monthly groundwater use (2014-2020) throughout this region at 1-km resolution, using pumping data from existing flowmeters in the Mississippi Delta. Our model compares favorably with the existing USGS model, with higher R2 (0.51 compared to 0.42 in the previous model), and lower root mean square error (RMSE) and mean absolute error (MAE)- 0.14 m and 0.09 m, respectively in our model, compared to 0.15 m and 0.1 m in the previous model. Therefore, this work advances our ability to predict groundwater use in regions with scarce or limited in-situ groundwater withdrawal data availability.

First posted April 5, 2021 For additional information, contact: Director, Lower Mississippi-Gulf Water Science CenterU.S. Geological Survey3535 S. Sherwood Forest Blvd., Suite 120 Baton Rouge, LA 70816 Information concerning the availability, use, and quality of water in St. Martin Parish, Louisiana, is critical for proper water-supply management. The purpose of this fact sheet is to present information that can be used by water managers, parish residents, and others for stewardship of this vital resource. In 2014, about 46.99 million gallons per day (Mgal/d) of water were withdrawn in St. Martin Parish, including about 35.91 Mgal/d from groundwater sources and 11.08 Mgal/d from surface-water sources. Withdrawals for agricultural use, composed of aquaculture (32.28 Mgal/d), rice irrigation (6.44 Mgal/d), general irrigation (2.38 Mgal/d), and livestock uses (0.06 Mgal/d), accounted for about 88 percent (41.16 Mgal/d) of the total water withdrawn. Other categories of use included public supply, which accounted for about 10 percent (4.83 Mgal/d), rural domestic, which accounted for about 2 percent (0.81 Mgal/d), and industry, which accounted for less than 1 percent (0.18 Mgal/d). Water-use data collected at 5-year intervals from 1960 to 2010 and again in 2014 indicate that water withdrawals in St. Martin Parish peaked in 1985 at more than 68 Mgal/d.

First posted April 5, 2021 For additional information, contact: Director, Lower Mississippi-Gulf Water Science CenterU.S. Geological Survey3535 S. Sherwood Forest Blvd., Suite 120 Baton Rouge, LA 70816 Information concerning the availability, use, and quality of water in Iberville Parish, Louisiana, is critical for proper water-supply management. The purpose of this fact sheet is to present information that can be used by water managers, parish residents, and others for stewardship of this vital resource. In 2014, about 589.87 million gallons per day (Mgal/d) of water were withdrawn in Iberville Parish in southeastern Louisiana: 30.86 Mgal/d from groundwater sources and 559.01 Mgal/d from surface-water sources. Withdrawals for industrial use accounted for about 77 percent (452.80 Mgal/d) of the total water withdrawn in 2016. Other use categories included power generation, which accounted for about 21 percent (124.54 Mgal/d), and aquaculture, which accounted for about 1 percent (7.50 Mgal/d). Water-use data collected at 5-year intervals from 1960 to 2010 and again in 2014 indicate that water withdrawals peaked in 1980 at 1,429.78 Mgal/d.

First posted September 28, 2020 For additional information, contact: Director, Lower Mississippi-Gulf Water Science CenterU.S. Geological Survey640 Grassmere Park, Suite 100Nashville, TN 37211 Water levels were determined in 90 wells to prepare 2011–12 potentiometric surfaces focusing primarily on the “200-foot,” 500-foot,” and “700-foot” sands of the Lake Charles area, which are part of the Chicot aquifer system underlying Calcasieu and Cameron Parishes of southwestern Louisiana. These three aquifers provided 34 percent of the total water withdrawn and 93 percent of the groundwater withdrawn in Calcasieu and Cameron Parishes in 2012 (84.5 million gallons per day [Mgal/d]). This work was completed by the U.S. Geological Survey, in cooperation with the Louisiana Department of Transportation and Development, to assist in developing and evaluating groundwater-resource management strategies. The highest water levels determined in wells screened in the “200-foot,” “500-foot,” and “700-foot” sands were about 8 feet (ft) above the National Geodetic Vertical Datum of 1929 (NGVD 29), 2 ft below NGVD 29, and 14 ft below NGVD 29, respectively, and were located in northwestern Calcasieu Parish. The lowest water levels determined in wells screened in the “200-foot,” “500-foot,” and “700-foot” sands were approximately 50, 80, and 70 ft below NGVD 29, respectively, and were located in the southern Lake Charles metropolitan area, to the west of Prien Lake, and between the cities of Lake Charles and Sulphur, respectively. The primary groundwater flow direction in these three aquifers was radially towards pumping centers overlying the water-level lows. Comparisons of water-level differences in 42 wells measured in 1995 and 2011–12 indicated that the maximum increases in water levels for wells screened in the “200-foot,” “500-foot,” and “700-foot” sands were approximately 7, 31, and 19 ft, respectively. Water-level increases coincided with a decline in total groundwater withdrawals during the period (about 25 Mgal/d from 1995 to 2012) from these sands. More specifically, withdrawals from the “500-foot” sand affected water levels in wells screened in the “200-foot” and “700-foot” sands because the three are hydraulically connected and withdrawals from the “500-foot” sand were greater by volume than withdrawals from the “200-foot” and “700-foot” sands.

First posted December 8, 2020 For additional information, contact: Director, Lower Mississippi-Gulf Water Science CenterU.S. Geological Survey3535 S. Sherwood Forest Blvd., Suite 120 Baton Rouge, LA 70816 Information concerning the availability, use, and quality of water in Pointe Coupee Parish, Louisiana, is critical for proper water-supply management. The purpose of this fact sheet is to present information that can be used by water managers, parish residents, and others for stewardship of this vital resource. In 2014, 364 million gallons per day (Mgal/d) of water were withdrawn in Pointe Coupee Parish, including about 39.87 Mgal/d from groundwater sources and 323.72 Mgal/d from surface-water sources. Withdrawals for power generation accounted for 89 percent (323.98 Mgal/d) of the total water withdrawn. Withdrawals for agricultural use, composed of aquaculture, general irrigation, livestock, and rice irrigation, accounted for 8 percent (29.29 Mgal/d) of the total water withdrawn. Other categories of use included public supply, industrial, and rural domestic. Water-use data collected at 5-year intervals from 1960 to 2010 and again in 2014 indicated that water withdrawals peaked in 2014. The large increase in surface-water withdrawals from 1980 to 1985 is attributable to an increase of 262 Mgal/d for power-generation use.

First posted December 21, 2020 For additional information, contact: Director, Lower Mississippi-Gulf Water Science CenterU.S. Geological Survey3535 S. Sherwood Forest Blvd., Suite 120 Baton Rouge, LA 70816 Information concerning the availability, use, and quality of water in Red River Parish, Louisiana, is critical for proper water-supply management. The purpose of this fact sheet is to present information that can be used by water managers, parish residents, and others for stewardship of this vital resource. In 2014, about 5.76 million gallons per day (Mgal/d) of water were withdrawn in Red River Parish: about 4.23 Mgal/d from groundwater sources and 1.54 Mgal/d from surface-water sources. Withdrawals for agricultural use, composed of general irrigation, rice irrigation, and livestock uses, accounted for about 72 percent (4.15 Mgal/d) of the total water withdrawn. Other categories of use included public supply (about 18 percent of the total water withdrawn, or 1.03 Mgal/d), industry (about 7 percent, or 0.39 Mgal/d), and rural domestic (about 4 percent, or 0.20 Mgal/d). Water-use data collected at 5-year intervals from 1960 to 2010 and again in 2014 indicated that water withdrawals peaked in 1975 at more than 7.3 Mgal/d.

First posted June 6, 2019 For additional information, contact: Director, Lower Mississippi-Gulf Water Science CenterU.S. Geological Survey3535 S. Sherwood Forest Blvd., Suite 120Baton Rouge, LA 70816 Information concerning the availability, use, and quality of water in Morehouse Parish, Louisiana, is critical for proper water-supply management. The purpose of this fact sheet is to present information that can be used by water managers, parish residents, and others for stewardship of this vital resource. In 2014, 109.84 million gallons per day (Mgal/d) of water were withdrawn in Morehouse Parish: 78.05 Mgal/d from groundwater sources and 31.79 Mgal/d from surface-water sources. Withdrawals for agricultural use—including general irrigation, rice irrigation, and livestock—accounted for about 97 percent (106.29 Mgal/d) of the total water withdrawn. Other categories of use included public supply, rural domestic, and industrial. Water-use data collected at 5-year intervals from 1960 to 2010 and again in 2014 indicated that water withdrawals peaked in 1975 at 167.82 Mgal/d.

First posted June 27, 2019 For additional information, contact: Director, Lower Mississippi-Gulf Water Science CenterU.S. Geological Survey3535 S. Sherwood Forest Blvd., Suite 120 Baton Rouge, LA 70816 Information concerning the availability, use, and quality of water in East Carroll Parish, Louisiana, is critical for proper water-supply management. The purpose of this fact sheet is to present information that can be used by water managers, parish residents, and others for stewardship of this vital resource. In 2014, 39.63 million gallons per day (Mgal/d) of water were withdrawn in East Carroll Parish: 32.43 Mgal/d from groundwater sources and 7.20 Mgal/d from surface-water sources. Withdrawals for agricultural use—composed of general irrigation, rice irrigation, and livestock—accounted for 97 percent (38.55 Mgal/d) of the total water withdrawn. Other categories of use included public supply and rural domestic. Water-use data collected at 5-year intervals from 1960 to 2010 and again in 2014 indicated that water withdrawals peaked in 1980 at 47.96 Mgal/d.

First posted June 13, 2019 For additional information, contact: Director, Lower Mississippi-Gulf Water Science CenterU.S. Geological Survey3535 S. Sherwood Forest Blvd., Suite 120 Baton Rouge, LA 70816 Information concerning the availability, use, and quality of water in Tensas Parish, Louisiana, is critical for proper water-supply management. The purpose of this fact sheet is to present information that can be used by water managers, parish residents, and others for stewardship of this vital resource. In 2014, 38.01 million gallons per day (Mgal/d) of water were withdrawn in Tensas Parish, including about 33.02 Mgal/d from groundwater sources and about 4.99 Mgal/d from surface-water sources. Withdrawals for agricultural use, composed of general irrigation, rice irrigation, aquaculture, and livestock, accounted for about 97 percent (36.88 Mgal/d) of the total water withdrawn. Other use categories included public supply and rural domestic. Water-use data collected at 5-year intervals from 1960 to 2010 and again in 2014 indicated that water withdrawals peaked in 2014. The large increase in 1985 relative to 1980 and 1990 for groundwater usage is likely an outlier that is attributable to a change in methodology for estimating rice irrigation. A transition in available farm-by-farm data from 1980 to 1985 to 1990 resulted in three different methods being used for estimating groundwater withdrawals for rice irrigation.

First posted June 20, 2019 For additional information, contact: Director, Lower Mississippi-Gulf Water Science CenterU.S. Geological Survey3535 S. Sherwood Forest Blvd., Suite 120 Baton Rouge, LA 70816 Information concerning the availability, use, and quality of water in Richland Parish, Louisiana, is critical for proper water-supply management. The purpose of this fact sheet is to present information that can be used by water managers, parish residents, and others for stewardship of this vital resource. In 2014, about 41.73 million gallons per day (Mgal/d) of water were withdrawn in Richland Parish, including about 28.57 Mgal/d from groundwater sources and 13.17 Mgal/d from surface-water sources. Withdrawals for agricultural use, composed of general irrigation, rice irrigation, aquaculture, and livestock uses, accounted for about 88 percent (36.88 Mgal/d) of the total water withdrawn. Other categories of use included public supply, which accounted for about 10 percent (4.38 Mgal/d) of the total water withdrawn and rural domestic which accounted for about 1 percent (0.48 Mgal/d). Water-use data collected at 5-year intervals from 1960 to 2010 and again in 2014 indicate that water withdrawals peaked in 1980 at more than 60 Mgal/d.

First posted June 26, 2019 For additional information, contact: Director, Lower Mississippi-Gulf Water Science CenterU.S. Geological Survey3535 S. Sherwood Forest Blvd., Suite 120 Baton Rouge, LA 70816 Information concerning the availability, use, and quality of water in Jackson Parish, Louisiana, is critical for proper water-supply management. The purpose of this fact sheet is to present information that can be used by water managers, parish residents, and others for stewardship of this vital resource. In 2014, about 4.38 million gallons per day (Mgal/d) of water were withdrawn in Jackson Parish: 4.36 Mgal/d from groundwater sources and 0.02 Mgal/d from surface-water sources. Withdrawals for public-supply use accounted for about 42 percent (1.85 Mgal/d) of the total water withdrawn, and industrial use accounted for about 54 percent (2.36 Mgal/d). Other categories of use included livestock and rural domestic. Water-use data collected at 5-year intervals from 1960 to 2010 and again in 2014 indicate that water withdrawals peaked in 1975 at about 15.26 Mgal/d. The significant decrease in water use from 1975 to 1980 was caused by a reduction of 10.38 Mgal/d in withdrawals for industrial use.

First posted March 1, 2017 For additional information, contact: Director, Lower Mississippi-Gulf Water Science Center U.S. Geological Survey 3535 S. Sherwood Forest Blvd. Suite 120 Baton Rouge, LA 70816 https://la.water.usgs.gov Information concerning the availability, use, and quality of groundwater in the 10 parishes overlying the Southern Hills regional aquifer system of Louisiana (fig. 1) is critical for water-supply management. The purpose of this fact sheet is to present information that can be used by water managers, residents, and others for stewardship of this vital resource. Information on the availability, past and current use, use trends, and water quality from groundwater sources in these parishes is presented. Previously published reports (see References Cited section) and data stored in the U.S. Geological Survey’s National Water Information System (U.S. Geological Survey, 2017) are the primary sources of the information presented here.

First posted November 23, 2016 For additional information, contact: Director, Lower Mississippi-Gulf Water Science CenterU.S. Geological Survey3535 S. Sherwood Forest Blvd., Suite 120,Baton Rouge, LA 70816http://la.water.usgs.gov Information concerning the availability, use, and quality of water in West Baton Rouge Parish, Louisiana, is critical for proper water-resource management. The purpose of this fact sheet is to present information that can be used by water managers, parish residents, and others for stewardship of this vital resource. Information on the availability, past and current use, use trends, and water quality from groundwater and surface-water sources in the parish is presented. Previously published reports and data stored in the U.S. Geological Survey’s National Water Information System (http://waterdata.usgs.gov/nwis) are the primary sources of the information presented here.

Information concerning the availability, use, and quality of water in St. John the Baptist Parish, Louisiana, is critical for proper water-supply management. The purpose of this fact sheet is to present information that can be used by water managers, parish residents, and others for stewardship of this vital resource. Information on the availability, past and current use, use trends, and water quality from groundwater and surface-water sources in the parish is presented. Previously published reports and data stored in the U.S. Geological Survey’s National Water Information System (http://waterdata.usgs.gov/nwis) are the primary sources of the information presented here.

Information concerning the availability, use, and quality of water in St. Charles Parish, Louisiana, is critical for proper water-supply management. The purpose of this fact sheet is to present information that can be used by water managers, parish residents, and others for stewardship of this vital resource. Information on the availability, past and current use, use trends, and water quality from groundwater and surface-water sources in the parish is presented. Previously published reports and data stored in the U.S. Geological Survey’s National Water Information System (http://waterdata.usgs.gov/nwis) are the primary sources of the information presented here.

Information concerning the availability, use, and quality of water in East Baton Rouge Parish, Louisiana, is critical for proper water-supply management. The purpose of this fact sheet is to present information that can be used by water managers, parish residents, and others for stewardship of this vital resource. Information on the availability, past and current use, use trends, and water quality from groundwater and surface-water sources in the parish is presented. Previously published reports and data stored in the U.S. Geological Survey’s National Water Information System (http://waterdata.usgs.gov/nwis) are the primary sources of the information presented here.

Information concerning the availability, use, and quality of water in La Salle Parish, Louisiana, is critical for proper water-supply management. The purpose of this fact sheet is to present information that can be used by water managers, parish residents, and others for stewardship of this vital resource. Information on the availability, past and current use, use trends, and water quality from groundwater and surface-water sources in the parish is presented. Previously published reports and data stored in the U.S. Geological Survey’s National Water Information System (http://waterdata.usgs.gov/nwis) are the primary sources of the information presented here.

Information concerning the availability, use, and quality of water in Orleans Parish, Louisiana, is critical for proper water-supply management. The purpose of this fact sheet is to present information that can be used by water managers, parish residents, and others for stewardship of this vital resource. Information on the availability, past and current use, use trends, and water quality from groundwater and surface-water sources in the parish is presented. Previously published reports and data stored in the U.S. Geological Survey’s National Water Information System (http://waterdata.usgs.gov/nwis) are the primary sources of the information presented here.