Clay Rural Water System, SD
Lead detected, under the action levels
Latest 90th-percentile lead: 1 ppb (monitoring period 2024-2024). The federal action level is 15 ppb today and drops to 10 ppb in Nov 2027; EPA's health goal is 0. Lead was measured in sampled homes but the 90th percentile is under both action levels. EPA's health goal for lead is zero, so test your own tap if your home was built before 1986 or anyone in it is pregnant or a young child.
About Clay Rural Water System
Clay Rural Water System serves about 4,780 people through 1,912 service connections, which makes it a medium-sized system under EPA's size classes. It is privately owned and draws groundwater, in Clay,Union County, South Dakota. EPA system ID: SD4600626; phone on file: 6052672088. Call that number and ask whether your address has a lead, galvanized or unknown service line.
Clay Rural Water System's lead record
That is down 2 ppb from 3 ppb in the period ending 2021. The highest 90th-percentile result EPA holds for Clay Rural Water System is 3 ppb across 3 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2024 | 1 ppb |
| 2021 | 3 ppb |
| 2018 | 1 ppb |
How Clay Rural Water System compares
Of the 458 South Dakota systems with a lead result, the median latest reading is 2 ppb; 0 are over 15 ppb right now and 6 have gone over at some point. Clay Rural Water System's 1 ppb sits at the 47th percentile in South Dakota and the 55th nationally (higher means more lead).
What to do in your house
Test your own tap with a certified lab first-draw sample; Wakonda, SD may offer free or low-cost kits through the utility. If your own line is lead, replacing the private side runs about $1,200-$12,300 (EPA average about $4,700). Ask Clay Rural Water System whether it covers that cost before hiring anyone - many utilities now do.
These figures describe homes the utility sampled, not your tap. Only your service line record or a test of your own water answers the question for your house. What a 90th-percentile result does and does not tell you: how to read a lead result. Size matters more than most people expect: small vs large water systems.