St. Tammany Parish County, Missouri — public water systems
At a glance
27 active public water systems are filed under St. Tammany Parish County, Missouri in EPA's SDWIS records, together reporting 45,833 people served. The largest is Magnolia-Eden Isles, which reports serving 10,155 people. All 27 are community water systems serving people where they live.
Dataset updated . Source: EPA SDWIS/ECHO, refreshed quarterly.
Active systems
27
Population served
45.8K
Community systems
27
Groundwater share
100%
How does St. Tammany Parish County compare with other Missouri counties?
St. Tammany Parish County has the 30th-most active public water systems among the 182 counties listed for active Missouri systems in EPA records; among the 132 with 3 or more systems, the median has 13. Its systems report 45,833 people served in total, the 23rd-largest county figure in the state and 0.8% of the statewide total. The average system here reports serving 1,698 people, about 17% below the Missouri average of 2,049. Population figures are what each system reports; people served by more than one system, such as a wholesaler and the town that buys from it, are counted by each.
Where does St. Tammany Parish County's drinking water come from?
By primary water source, St. Tammany Parish County's active systems draw on groundwater (27, 100%). Overall, all rely mainly on groundwater (including purchased groundwater) and none on surface water, compared with 92% and 8.1% across Missouri. Groundwater means the system draws its water from wells or springs fed by underground aquifers. The county's largest system, Magnolia-Eden Isles, draws primarily on groundwater.
What kinds of water systems operate in St. Tammany Parish County?
St. Tammany Parish County's active systems break down as 27 community systems (100%). A community water system serves at least 15 connections used by year-round residents, or regularly serves at least 25 year-round residents. Homes, apartments and mobile-home parks are served by these. EPA lists their owner types as private (100%).
Water systems in St. Tammany Parish County
🔒 Create a free account to export CSV| # | Water system | County | Population served | Type | Source |
|---|---|---|---|---|---|
| 1 | Magnolia-Eden Isles | St. Tammany Parish | 10,155 | Community | Groundwater |
| 2 | Magnolia-Greenleaves | St. Tammany Parish | 8,031 | Community | Groundwater |
| 3 | Magnolia-Resolve Whisperwood | St. Tammany Parish | 6,867 | Community | Groundwater |
| 4 | Magnolia-the Meadows | St. Tammany Parish | 4,701 | Community | Groundwater |
| 5 | Magnolia-Lakeshore Estates | St. Tammany Parish | 4,146 | Community | Groundwater |
| 6 | Magnolia-Guste Island | St. Tammany Parish | 2,847 | Community | Groundwater |
| 7 | Magnolia-Monterey Subdivision | St. Tammany Parish | 1,356 | Community | Groundwater |
| 8 | Magnolia-Penn Mill Lakes | St. Tammany Parish | 1,152 | Community | Groundwater |
| 9 | Magnolia-Money Hills Estates | St. Tammany Parish | 825 | Community | Groundwater |
| 10 | Magnolia-River Park | St. Tammany Parish | 822 | Community | Groundwater |
| 11 | Magnolia-Brier Lake Utilities Inc. | St. Tammany Parish | 630 | Community | Groundwater |
| 12 | Magnolia-Grande Palms | St. Tammany Parish | 579 | Community | Groundwater |
| 13 | Magnolia-Oaklawn Trace | St. Tammany Parish | 480 | Community | Groundwater |
| 14 | Magnolia-Bleu Lake Hills | St. Tammany Parish | 420 | Community | Groundwater |
| 15 | Magnolia-Pruden Creek | St. Tammany Parish | 324 | Community | Groundwater |
| 16 | Magnolia Water Utilites - Cherrywood | St. Tammany Parish | 306 | Community | Groundwater |
| 17 | Magnolia-Rigolets Estates | St. Tammany Parish | 273 | Community | Groundwater |
| 18 | Magnolia-Autumn Haven | St. Tammany Parish | 267 | Community | Groundwater |
| 19 | Magnolia-I59 MHP | St. Tammany Parish | 255 | Community | Groundwater |
| 20 | Magnolia-Beau Pre | St. Tammany Parish | 240 | Community | Groundwater |
| 21 | Magnolia-Homeland Height | St. Tammany Parish | 234 | Community | Groundwater |
| 22 | Magnolia-Port Louis Townhomes | St. Tammany Parish | 200 | Community | Groundwater |
| 23 | Magnolia-Rigolets Harbor | St. Tammany Parish | 200 | Community | Groundwater |
| 24 | Magnolia-Pilot Street | St. Tammany Parish | 174 | Community | Groundwater |
| 25 | Magnolia-Penn Mill Place | St. Tammany Parish | 171 | Community | Groundwater |
| 26 | Magnolia-Beverly Heights | St. Tammany Parish | 100 | Community | Groundwater |
| 27 | Magnolia-Whippoorwill Grove | St. Tammany Parish | 78 | Community | Groundwater |
St. Tammany Parish County water systems: frequently asked questions
How many public water systems are in St. Tammany Parish County, Missouri?
EPA's SDWIS records file 27 active public water systems under St. Tammany Parish County, Missouri: 27 community systems (100%).
Who supplies drinking water in St. Tammany Parish County, MO?
The largest community water systems filed under St. Tammany Parish County are Magnolia-Eden Isles (10,155 people served), Magnolia-Greenleaves (8,031 people served) and Magnolia-Resolve Whisperwood (6,867 people served). Which system serves a particular address depends on its service area, which EPA's SDWIS records do not include; a water bill or the local utility can confirm it.
Does St. Tammany Parish County's drinking water come from groundwater or surface water?
Of the 27 active public water systems in St. Tammany Parish County, all draw mainly on groundwater and none on surface water, counting purchased supplies. The largest system, Magnolia-Eden Isles, uses groundwater.
Where can I find a water quality report for St. Tammany Parish County?
Each community water system must deliver an annual water quality report, called a Consumer Confidence Report, to its customers by July 1, covering the previous calendar year. 27 community systems are filed under St. Tammany Parish County, so the report to look for is the one from the system that supplies your address.
How can I check violations for a water system in St. Tammany Parish County?
Open the system's profile from the list on this page. Each profile shows the most recent Safe Drinking Water Act violations in EPA's records, with plain-English labels and whether each one is resolved. For current compliance status, EPA ECHO is the primary source.
More Missouri water systems
- All Missouri public water systems· 2,943 active
- Montgomery County· 29 systems
- Jackson County· 29 systems
- Cape Girardeau County· 29 systems
- Reynolds County· 29 systems
- Webster County· 27 systems
- Warren County· 27 systems
- How to find out who supplies your drinking water
- How to find and read your annual water quality report
About this data
Source: U.S. EPA Safe Drinking Water Information System (SDWIS) and SDWA violation records, via EPA ECHO, as published October 1, 2026 — AquaCensus refreshes it quarterly. See the methodology for how records are matched, cleaned and scored.
Cite as: AquaCensus, “Public water systems in St. Tammany Parish County, Missouri”, https://aquacensus.com/water-systems/missouri/st-tammany-parish (data as of October 1, 2026).