| Village of Fenton Water System | Fenton | 226 | 0.0170 mg/L |
| Cajun Mobile Home Park Water System | Youngsville | 168 | 0.0130 mg/L |
| St Martin Industrial Park Water System | St. Martinville | 150 | 0.0130 mg/L |
| Town of Campti Water System | Campti | 1,515 | 0.0122 mg/L |
| Town of Ferriday Water System | Ferriday | 3,816 | 0.0114 mg/L |
| Lakeview Water System | Shreveport | 2,025 | 0.0113 mg/L |
| Autumn Acres Mhp Water System | Keithville | 90 | 0.0110 mg/L |
| Town of Greenwood Water System | Greenwood | 5,205 | 0.0100 mg/L |
| Monterey Rural Water System Inc | Monterey | 5,250 | 0.0093 mg/L |
| Town of Grambling Water System | Grambling | 4,949 | 0.0090 mg/L |
| Village of Mooringsport Water System | Mooringsport | 999 | 0.0090 mg/L |
| Village of Epps Water System | Epps | 594 | 0.0090 mg/L |
| Veterans Administration | Alexandria | 1,330 | 0.0082 mg/L |
| Iberia Water Works District 3 - Coteau | New Iberia | 8,775 | 0.0080 mg/L |
| Town of Kentwood Water System | Kentwood | 2,205 | 0.0080 mg/L |
| Poland Water Association | Echo | 1,044 | 0.0080 mg/L |
| Village of Bienville Water System | Bienville | 360 | 0.0080 mg/L |
| Woodside Mhp | — | 150 | 0.0080 mg/L |
| New Orleans Algiers Water Works | — | 52,785 | 0.0071 mg/L |
| Town of Mamou Water System | Mamou | 4,559 | 0.0070 mg/L |
| St Tammany Water District 3 | Covington | 2,920 | 0.0070 mg/L |
| Lawco - Mansura Water System | — | 1,878 | 0.0070 mg/L |
| Town of Grand Coteau Water System | Grand Coteau | 1,650 | 0.0070 mg/L |
| Glen Leaf Mobile Home Community | Shreveport | 645 | 0.0070 mg/L |
| Village of Bonita Water System | Bonita | 426 | 0.0070 mg/L |
| Cheniere Drew South Water System | West Monroe | 1,563 | 0.0067 mg/L |
| New Orleans Carrollton Water Works | — | 334,903 | 0.0060 mg/L |
| Pinehill Waterworks District | Shreveport | 4,926 | 0.0060 mg/L |
| Town of Jonesville Water System | Jonesville | 2,811 | 0.0060 mg/L |
| Summerville Water System | Jena | 1,425 | 0.0060 mg/L |
| Village of Dry Prong Water System | Dry Prong | 1,155 | 0.0060 mg/L |
| Alabama Water System | Arcadia | 948 | 0.0060 mg/L |
| G & J Mobile Home Estates Water System | Lafayette | 186 | 0.0060 mg/L |
| Lakeview Trailer Park Water System | Milton | 30 | 0.0060 mg/L |
| Monticello Water System | Lake Providence | 1,104 | 0.0054 mg/L |
| Friendship Water System | Saline | 717 | 0.0052 mg/L |
| Town of Delcambre Water System | Delcambre | 2,457 | 0.0051 mg/L |
| Port Sulphur Water District | Belle Chasse | 10,308 | 0.0050 mg/L |
| St James Water District 1 | Convent | 7,200 | 0.0050 mg/L |
| Town of Oak Grove Water System | Oak Grove | 2,955 | 0.0050 mg/L |
| Wards 4 & 5 Water System | Grayson | 1,002 | 0.0050 mg/L |
| Bistineau Water System | Heflin | 882 | 0.0050 mg/L |
| Fellowship Water System | Simsboro | 795 | 0.0050 mg/L |
| Adventures Rv Resort | Robert | 635 | 0.0050 mg/L |
| Halfway-Carroll Water System | Coushatta | 498 | 0.0050 mg/L |
| St Tam Parish - Northlake Behavioral | Covington | 480 | 0.0050 mg/L |
| Springhill Community Water System | Ringgold | 183 | 0.0050 mg/L |
| St Charles Mobile Home Park | Independence | 175 | 0.0050 mg/L |
| Town of Homer Water System | — | 4,524 | 0.0047 mg/L |
| Henderson Nina Water System Inc | Breaux Bridge | 5,535 | 0.0046 mg/L |
| West Winn Water System Inc | Winnfield | 1,965 | 0.0046 mg/L |
| Zone 2 Water System Inc. | Colfax | 1,344 | 0.0045 mg/L |
| Settled Inn Village Water System | Shreveport | 108 | 0.0045 mg/L |
| Azalea Lane Trailer Park | Slidell | 84 | 0.0043 mg/L |
| Jeff Davis Central Waterworks District | Welsh | 5,709 | 0.0042 mg/L |
| Goodwill Water System | Oak Grove | 1,929 | 0.0042 mg/L |
| Bastrop Water System | Bastrop | 18,105 | 0.0040 mg/L |
| Milton Water System | Milton | 10,200 | 0.0040 mg/L |
| Calcasieu Parish Ww District 8 | Lake Charles | 6,834 | 0.0040 mg/L |
| Calcasieu Parish Ww District No 5 | Lake Charles | 5,088 | 0.0040 mg/L |
| Avoyelles Ward One Water System Inc | Effie | 3,726 | 0.0040 mg/L |
| Fairview Union Water System | Coushatta | 2,346 | 0.0040 mg/L |
| Northwest Allen Parish Ww District | Grant | 1,767 | 0.0040 mg/L |
| Ascension Parish Water Works District 2 | — | 1,353 | 0.0040 mg/L |
| Cypress Water System | Ringgold | 1,125 | 0.0040 mg/L |
| Town of Merryville Water System | Merryville | 1,107 | 0.0040 mg/L |
| Village of Collinston Water System | Collinston | 609 | 0.0040 mg/L |
| Village of Fisher Water System | Fisher | 348 | 0.0040 mg/L |
| Diversion Water - Stonehill | — | 225 | 0.0040 mg/L |
| Glencoe Community Water System | — | 190 | 0.0040 mg/L |
| My Place Mobile Home Park Water System | — | 111 | 0.0040 mg/L |
| Pine Trailer Park | — | 60 | 0.0040 mg/L |
| Oak River Estates | Covington | 25 | 0.0040 mg/L |
| Fiske Union Water System | Oak Grove | 1,830 | 0.0038 mg/L |
| Village of Florien Water System | Florien | 700 | 0.0035 mg/L |
| St Mary Water & Sewer Comm #3 | Centerville | 7,828 | 0.0033 mg/L |
| Diversion Water- Water Front West | — | 1,548 | 0.0032 mg/L |
| Vernon Parish Water and Sewer Commission | New Llano | 5,295 | 0.0031 mg/L |
| St Mary Par Jt Water Sewer Commission 5 | — | 1,240 | 0.0031 mg/L |
| Village of Saline Water System | Saline | 450 | 0.0031 mg/L |
| Latanier Water Association | Alexandria | 357 | 0.0031 mg/L |
| Lawco - Crowley Water System | — | 17,733 | 0.0030 mg/L |
| West Hwy 80 Ark Road Ws | West Monroe | 14,649 | 0.0030 mg/L |
| City of Abbeville Water System | Abbeville | 14,217 | 0.0030 mg/L |
| Cecilia Water Corporation | Cecilia | 12,420 | 0.0030 mg/L |
| Southwest Ouachita Waterworks, Inc | West Monroe | 10,725 | 0.0030 mg/L |
| Bayou Teche Water Works | — | 10,137 | 0.0030 mg/L |
| Jeff Davis Water and Sewer Commission 1 | Lake Arthur | 9,780 | 0.0030 mg/L |
| City of Jeanerette Water System | Jeanerette | 6,189 | 0.0030 mg/L |
| Town of Welsh Water System | Welsh | 4,311 | 0.0030 mg/L |
| Varnado Water Works | Angie | 4,230 | 0.0030 mg/L |
| Town of Vinton Water System | Vinton | 4,101 | 0.0030 mg/L |
| Lena Water System Inc | Lena | 3,540 | 0.0030 mg/L |
| West Grant Water Association | Alanta | 3,324 | 0.0030 mg/L |
| Village of Palmetto Water System | Palmetto | 2,178 | 0.0030 mg/L |
| Town of Gueydan Water System | Gueydan | 2,016 | 0.0030 mg/L |
| Tannehill Water System | Winnfield | 1,932 | 0.0030 mg/L |
| Pleasant Valley Water System | Minden | 1,683 | 0.0030 mg/L |
| Hico Water System | Dubach | 1,530 | 0.0030 mg/L |
| Town of St Joseph Water System | St Joseph | 1,332 | 0.0030 mg/L |