Private Well Water Testing in Mississippi
County-by-county USGS area-risk estimates for private wells across Mississippi โ arsenic exceedance probability and private-well population โ plus how to test your own well at a Mississippi-certified laboratory.
Mississippi private-well risk summary
Counties covered
82
Mississippi counties with modeled risk data.
People on private wells
area estimate365,793
estimated across covered Mississippi counties.
Average arsenic risk
area estimate2%
average modeled chance a well exceeds 10 ยตg/L arsenic across covered counties.
Mississippi counties
- Jackson County4% arsenic exceedance (area estimate)34,487 people on private wells
- Harrison County5% arsenic exceedance (area estimate)31,635 people on private wells
- Marshall County3% arsenic exceedance (area estimate)22,118 people on private wells
- Pearl River County3% arsenic exceedance (area estimate)18,274 people on private wells
- Hancock County2% arsenic exceedance (area estimate)16,678 people on private wells
- Lincoln County4% arsenic exceedance (area estimate)15,068 people on private wells
- Tate County2% arsenic exceedance (area estimate)13,687 people on private wells
- George County3% arsenic exceedance (area estimate)13,624 people on private wells
- Pike County3% arsenic exceedance (area estimate)10,200 people on private wells
- DeSoto County3% arsenic exceedance (area estimate)9,065 people on private wells
- Stone County4% arsenic exceedance (area estimate)8,091 people on private wells
- Lowndes County1% arsenic exceedance (area estimate)7,882 people on private wells
- Lauderdale County1% arsenic exceedance (area estimate)7,158 people on private wells
- Union County1% arsenic exceedance (area estimate)7,084 people on private wells
- Amite County4% arsenic exceedance (area estimate)6,392 people on private wells
- Walthall County3% arsenic exceedance (area estimate)6,257 people on private wells
- Benton County2% arsenic exceedance (area estimate)5,566 people on private wells
- Marion County3% arsenic exceedance (area estimate)5,130 people on private wells
- Washington County3% arsenic exceedance (area estimate)4,663 people on private wells
- Newton County1% arsenic exceedance (area estimate)4,494 people on private wells
- Panola County2% arsenic exceedance (area estimate)4,468 people on private wells
- Lafayette County2% arsenic exceedance (area estimate)4,449 people on private wells
- Hinds County3% arsenic exceedance (area estimate)4,309 people on private wells
- Greene County2% arsenic exceedance (area estimate)4,195 people on private wells
- Lamar County3% arsenic exceedance (area estimate)4,152 people on private wells
- Wayne County2% arsenic exceedance (area estimate)3,968 people on private wells
- Bolivar County3% arsenic exceedance (area estimate)3,825 people on private wells
- Monroe County1% arsenic exceedance (area estimate)3,792 people on private wells
- Rankin County2% arsenic exceedance (area estimate)3,516 people on private wells
- Pontotoc County1% arsenic exceedance (area estimate)3,055 people on private wells
- Clarke County1% arsenic exceedance (area estimate)2,894 people on private wells
- Noxubee County1% arsenic exceedance (area estimate)2,854 people on private wells
- Sunflower County2% arsenic exceedance (area estimate)2,818 people on private wells
- Tippah County2% arsenic exceedance (area estimate)2,779 people on private wells
- Perry County3% arsenic exceedance (area estimate)2,763 people on private wells
- Leflore County2% arsenic exceedance (area estimate)2,650 people on private wells
- Leake County2% arsenic exceedance (area estimate)2,626 people on private wells
- Lee County1% arsenic exceedance (area estimate)2,546 people on private wells
- Forrest County3% arsenic exceedance (area estimate)2,525 people on private wells
- Alcorn County1% arsenic exceedance (area estimate)2,355 people on private wells
- Attala County3% arsenic exceedance (area estimate)2,309 people on private wells
- Itawamba County1% arsenic exceedance (area estimate)2,297 people on private wells
- Simpson County3% arsenic exceedance (area estimate)2,296 people on private wells
- Franklin County3% arsenic exceedance (area estimate)2,226 people on private wells
- Jones County2% arsenic exceedance (area estimate)2,100 people on private wells
- Madison County2% arsenic exceedance (area estimate)2,038 people on private wells
- Coahoma County2% arsenic exceedance (area estimate)1,998 people on private wells
- Neshoba County1% arsenic exceedance (area estimate)1,974 people on private wells
- Clay County1% arsenic exceedance (area estimate)1,968 people on private wells
- Tallahatchie County3% arsenic exceedance (area estimate)1,718 people on private wells
- Grenada County3% arsenic exceedance (area estimate)1,637 people on private wells
- Carroll County4% arsenic exceedance (area estimate)1,572 people on private wells
- Copiah County4% arsenic exceedance (area estimate)1,521 people on private wells
- Yazoo County4% arsenic exceedance (area estimate)1,506 people on private wells
- Tunica County2% arsenic exceedance (area estimate)1,497 people on private wells
- Adams County3% arsenic exceedance (area estimate)1,490 people on private wells
- Covington County2% arsenic exceedance (area estimate)1,370 people on private wells
- Scott County1% arsenic exceedance (area estimate)1,351 people on private wells
- Lawrence County3% arsenic exceedance (area estimate)1,348 people on private wells
- Chickasaw County1% arsenic exceedance (area estimate)1,311 people on private wells
- Prentiss County1% arsenic exceedance (area estimate)1,282 people on private wells
- Humphreys County2% arsenic exceedance (area estimate)1,226 people on private wells
- Holmes County3% arsenic exceedance (area estimate)1,209 people on private wells
- Tishomingo County1% arsenic exceedance (area estimate)1,070 people on private wells
- Warren County5% arsenic exceedance (area estimate)997 people on private wells
- Wilkinson County4% arsenic exceedance (area estimate)933 people on private wells
- Smith County1% arsenic exceedance (area estimate)887 people on private wells
- Sharkey County3% arsenic exceedance (area estimate)882 people on private wells
- Oktibbeha County2% arsenic exceedance (area estimate)880 people on private wells
- Jefferson Davis County3% arsenic exceedance (area estimate)829 people on private wells
- Calhoun County1% arsenic exceedance (area estimate)713 people on private wells
- Yalobusha County2% arsenic exceedance (area estimate)678 people on private wells
- Quitman County2% arsenic exceedance (area estimate)660 people on private wells
- Jasper County1% arsenic exceedance (area estimate)523 people on private wells
- Choctaw County2% arsenic exceedance (area estimate)510 people on private wells
- Kemper County1% arsenic exceedance (area estimate)507 people on private wells
- Winston County3% arsenic exceedance (area estimate)486 people on private wells
- Webster County2% arsenic exceedance (area estimate)472 people on private wells
- Montgomery County1% arsenic exceedance (area estimate)430 people on private wells
- Issaquena County3% arsenic exceedance (area estimate)372 people on private wells
- Claiborne County6% arsenic exceedance (area estimate)352 people on private wells
- Jefferson County4% arsenic exceedance (area estimate)276 people on private wells
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Upload my well testThese figures are USGS area estimates: statistical groundwater models describing how likely elevated contaminant levels are across a county. They are not designed to predict the concentration in any single well. Only testing your own well reveals its water quality.
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