South Dakota
Union County drinking water quality
10 active public water systems serve 24,117 people in Union County. 8 are compliant, 2 had at least one EPA violation in the past three years, 0 are designated serious violators, and 0 carry a health flag.
Community water systems
9 systems, largest first| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
South Lincoln Rural Water System Beresford, Worthing |
5,250 | 1 | 0 | |
|
Clay Rural Water System Wakonda |
4,780 | 0 | 0 | |
|
Dakota Dunes Cid Dakota Dunes |
3,700 | 0 | 0 | |
|
North Sioux City North Sioux City |
3,042 | 0 | 0 | |
|
Beresford Beresford |
2,359 | 0 | 0 | |
|
Elk Point Elk Point |
2,124 | 0 | 0 | |
|
Clay Rws/south Union Wakonda |
1,447 | 0 | 0 | |
|
Alcester Alcester |
820 | 2 | 0 | |
|
Jefferson Jefferson |
475 | 0 | 0 |
Non-community systems (1: schools, campgrounds, workplaces, restaurants)
These systems serve places people visit rather than homes.
| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
Two Rivers Golf Club Dakota Dunes |
120 | 0 | 0 |
Inactive systems (10, no longer operating or reporting)
Kept for the record and excluded from the county totals above. Browse inactive systems.
About this data
Totals cover active systems. Systems serving more than one county are counted in each county. EPA counts the rules a system was in violation of, not the individual violations; one rule can carry several.
Source: the U.S. EPA's Enforcement and Compliance History Online system (ECHO), which publishes the federal Safe Drinking Water Information System. EPA's terms and values are shown as published. The South Dakota records are from EPA's data refresh of Oct 7, 2026; EPA refreshes this data quarterly, and states report to EPA with a lag of three to six months, so the newest violations may not appear yet. Retrieved from ECHO on Oct 11, 2026.