Water hardness in Missouri, characterized by the amount of dissolved minerals such as calcium and magnesium, can significantly differ among various cities across the state due to its varied geological landscapes. Situated in the Midwest of the U.S., Missouri’s water hardness levels reflect the geological diversity within the state.
Across Missouri, water hardness can range from moderately soft to very hard, depending on the geological makeup of the area and the source of the water supply. For example, regions with limestone bedrock, such as those in central and southern Missouri, often have harder water due to the high mineral content. In contrast, areas with more sandstone or shale bedrock may experience softer water.
The variation in water hardness throughout Missouri influences not only the taste and aesthetics of the water but also the efficiency of soaps and detergents, plumbing maintenance, and the lifespan of appliances that utilize water. Given the state’s geological diversity, water hardness is not uniform, highlighting the need for localized water treatment solutions and ongoing monitoring of water quality.
In the provided data, the water hardness levels show substantial variations across different cities in Missouri. Among the cities for which data is reported, the highest water hardness level is recorded in Park Hills with a hardness of 565.0 ppm, 33.0 gpg. Conversely, the city with the lowest recorded water hardness level is Kennett, reporting a hardness of 77.0 ppm, 4.5 gpg.
| City | Hardness ppm (mg/L) | Hardness gpg | Information Source | Notes |
| Kansas City | 280.0 | 16.4 | Link | |
| St. Louis | 146.0 | 8.5 | Link | |
| Springfield | 142.5 | 8.3 | Link | |
| Columbia | 210.0 | 12.3 | Link | |
| Independence | 137.0 | 8.0 | Link | |
| Lee’s Summit | 131.0 | 7.7 | Link | |
| O’Fallon | 203.0 | 11.9 | Link | |
| St. Joseph | 219.0 | 12.8 | Link | |
| St. Charles | 127.0 | 7.4 | Link | |
| Blue Springs | 141.0 | 8.2 | Link | |
| St. Peters | 173.0 | 10.1 | Link | |
| Florissant | 146.0 | 8.5 | Link | Covered under St. Louis |
| Joplin | 163.0 | 9.5 | Link | |
| Chesterfield | 146.0 | 8.5 | Link | Covered under St. Louis |
| Wentzville | 296.0 | 17.3 | Link | |
| Jefferson City | 140.0 | 8.2 | Link | |
| Cape Girardeau | 123.0 | 7.2 | Link | |
| Wildwood | 319.0 | 18.6 | Link | |
| University City | 146.0 | 8.5 | Link | Covered under St. Louis |
| Ballwin | 265.0 | 15.5 | Link | |
| Liberty | 169.0 | 9.9 | Link | |
| Raytown | 131.0 | 7.7 | Link | |
| Kirkwood | 146.0 | 8.5 | Link | Covered under St. Louis |
| Maryland Heights | 146.0 | 8.5 | Link | Covered under St. Louis |
| Gladstone | 104.0 | 6.1 | Link | |
| Grandview | 404.0 | 23.6 | Link | |
| Hazelwood | 146.0 | 8.5 | Link | Covered under St. Louis |
| Belton | 280.0 | 16.4 | Link | Buys from Kansas City |
| Raymore | 141.0 | 8.2 | Link | |
| Nixa | 190.0 | 11.1 | Link | |
| Webster Groves | 146.0 | 8.5 | Link | Covered under St. Louis |
| Ozark | 189.5 | 11.1 | Link | |
| Sedalia | 244.5 | 14.3 | Link | |
| Arnold | 146.0 | 8.5 | Link | Purchases from St. Louis |
| Rolla | 381.0 | 22.3 | Link | |
| Warrensburg | 222.0 | 13.0 | Link | |
| Republic | 156.5 | 9.1 | Link | |
| Creve Coeur | 146.0 | 8.5 | Link | Covered under St. Louis |
| Ferguson | 146.0 | 8.5 | Link | Covered under St. Louis |
| Farmington | 356.0 | 20.8 | Link | |
| Manchester | 146.0 | 8.5 | Link | Covered under St. Louis |
| Kirksville | 133.0 | 7.8 | Link | |
| Lake St. Louis | 146.0 | 8.5 | Link | Covered under St. Louis |
| Hannibal | 183.0 | 10.7 | Link | |
| Clayton | 210.0 | 12.3 | Link | Covered under St. Louis |
| Poplar Bluff | 99.9 | 5.8 | Link | |
| Sikeston | 174.5 | 10.2 | Link | |
| Grain Valley | 141.0 | 8.2 | Link | |
| Overland | 146.0 | 8.5 | Link | Covered under St. Louis |
| Carthage | 153.5 | 9.0 | Link | |
| Jackson | 307.0 | 17.9 | Link | |
| Lebanon | 195.5 | 11.4 | Link | |
| Washington | 253.0 | 14.8 | Link | |
| Moberly | 139.0 | 8.1 | Link | |
| Marshall | 126.0 | 7.4 | Link | |
| Troy | 262.0 | 15.3 | Link | |
| Webb City | 171.0 | 10.0 | Link | |
| Dardenne Prairie | 235.0 | 13.7 | Link | |
| St. Ann | 146.0 | 8.5 | Link | Covered under St. Louis |
| Jennings | 146.0 | 8.5 | Link | Covered under St. Louis |
| Branson | 122.0 | 7.1 | Link | |
| Festus | 90.3 | 5.3 | Link | |
| Fulton | 296.5 | 17.3 | Link | |
| Neosho | 166.0 | 9.7 | Link | |
| Union | 244.5 | 14.3 | Link | |
| Crestwood | 146.0 | 8.5 | Link | Covered under St. Louis |
| West Plains | 228.0 | 13.3 | Link | |
| Eureka | 230.5 | 13.5 | Link | |
| Mexico | 300.0 | 17.5 | Link | |
| Town and Country | 146.0 | 8.5 | Link | Covered under St. Louis |
| Bridgeton | 146.0 | 8.5 | Link | Covered under St. Louis |
| Bolivar | 216.5 | 12.6 | Link | |
| Maryville | 125.0 | 7.3 | Link | |
| Kearney | 135.0 | 7.9 | Link | |
| Bellefontaine Neighbors | 146.0 | 8.5 | Link | Covered under St. Louis |
| Excelsior Springs | 112.0 | 6.5 | Link | |
| Smithville | 116.0 | 6.8 | Link | |
| Kennett | 77.0 | 4.5 | Link | |
| Harrisonville | 122.0 | 7.1 | Link | |
| Ellisville | 146.0 | 8.5 | Link | Covered under St. Louis |
| Monett | 132.5 | 7.7 | Link | |
| Clinton | 152.0 | 8.9 | Link | |
| Richmond Heights | 146.0 | 8.5 | Link | Covered under St. Louis |
| Des Peres | 146.0 | 8.5 | Link | Covered under St. Louis |
| Sunset Hills | 146.0 | 8.5 | Link | Covered under St. Louis |
| Chillicothe | 120.0 | 7.0 | Link | |
| Ladue | 146.0 | 8.5 | Link | Covered under St. Louis |
| Warrenton | 255.0 | 14.9 | Link | |
| Pleasant Hill | 141.0 | 8.2 | Link | |
| Park Hills | 565.0 | 33.0 | Link | |
| Perryville | 205.5 | 12.0 | Link | |
| Olivette | 146.0 | 8.5 | Link | Covered under St. Louis |
| Cameron | 156.0 | 9.1 | Link | |
| Oak Grove | 131.0 | 7.7 | Link | |
| Carl Junction | 171.0 | 10.0 | Link | |
| Nevada | 95.5 | 5.6 | Link | |
| Maplewood | 146.0 | 8.5 | Link | Covered under St. Louis |
| Brentwood | 146.0 | 8.5 | Link | Covered under St. Louis |
| Berkeley | 146.0 | 8.5 | Link | Covered under St. Louis |
| Dexter | 195.0 | 11.4 | Link |
ppm = Parts Per Million
mg/L = Milligrams Per Liter
gpg = Grains Per Gallon
Hard water can cause issues such as mineral buildup in plumbing and appliances, reduce the efficacy of soaps and detergents, and affect the taste of the water. A tried and true solution is the use of a water softener. A water softener, like the ones from DROP, could be a worthwhile investment.
These devices work by replacing the calcium and magnesium ions that cause hardness with sodium ions, resulting in softer water. With innovative features, easy installation, and efficient operation, DROP smart water softeners provide a solution to hard water issues, extending the lifespan of appliances, improving water taste, enhancing soap effectiveness, reducing scale build-up, and increasing the overall water efficiency in your home.
