Mississippi River
River · Central
0Slightly
60Moderate
120Hard
180Very Hard
250Extreme
400+
About Mississippi River
The Mississippi River is the largest river system in North America, draining 31 states. Cities from Minneapolis to New Orleans draw their drinking water from it, each inheriting the upstream discharges of millions of people.
Geography & Hydrology
The river flows 2,320 miles from Lake Itasca in Minnesota to the Gulf of Mexico. The drainage basin covers 1.25 million square miles — 41% of the contiguous United States. By the time the water reaches New Orleans, it has passed through agricultural, industrial, and urban areas.
How Mississippi River Water Is Treated
Advanced treatment is essential due to upstream contamination. Most plants use multiple stages including coagulation, sedimentation, ozone or UV, granular activated carbon, and chloramine. New Orleans and Baton Rouge have invested heavily in advanced treatment.
Across the 17 cities we track, water from Mississippi River averages 163 PPM hardness (Hard), ranging from 60 to 295 PPM. This is moderately hard - many homeowners notice scale buildup on fixtures over time.
PFAS concern: Cities supplied by Mississippi River average 19.7 ppt PFAS, exceeding the 2024 EPA limit of 4 ppt. An NSF P473 certified filter is recommended for drinking water.
Current Challenges
Agricultural runoff (nitrates, pesticides, herbicides), pharmaceutical contamination, microplastics, seasonal flooding affecting treatment plant intake, and a dead zone in the Gulf of Mexico from nutrient overloading.
Cities Supplied by Mississippi River
Water quality varies by city due to local treatment, distribution infrastructure, and source blending.
St. Louis, MO
1,111,000 residentsMinneapolis, MN
425,300 residentsSt. Paul, MN
392,529 residentsSt. Paul East, MN
392,529 residentsNew Orleans, LA
334,903 residentsKenner, LA
334,903 residentsMetairie, LA
334,903 residentsMarrero, LA
334,903 residentsNew Orleans Downtown, LA
334,903 residentsNew Orleans Uptown, LA
334,903 residentsDavenport, IA
147,720 residentsBloomington, MN
91,300 residentsBrooklyn Park, MN
89,995 residentsSt. Cloud, MN
71,321 residentsDubuque, IA
59,667 residentsBelleville, IL
463 residentsBettendorf, IA
220 residentsRecommended for Mississippi River Water
Based on average water quality across 17 cities supplied by Mississippi River.
Affiliate disclosure: we may earn a commission on purchases. Recommendations based on water quality data.