Buffalo Gap, SD
Lead detected, under the action levels
Latest 90th-percentile lead: 2 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 Buffalo Gap
Buffalo Gap serves about 126 people through 93 service connections, which makes it a very small system under EPA's size classes. It is owned by a local government (city, town, county or district) and draws groundwater, in Custer County, South Dakota. EPA system ID: SD4600077. Ask the utility on your bill for your address in their service line inventory.
Lead results over time
Against the period ending 2020 (2 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Buffalo Gap is 3 ppb across 3 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2024 | 2 ppb |
| 2020 | 2 ppb |
| 2017 | 3 ppb |
Where this result ranks
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. Buffalo Gap's 2 ppb sits at the 58th percentile in South Dakota and the 70th nationally (higher means more lead).
Other water systems in Custer County
9 other systems share Custer County; 3 of them have a higher latest lead result than Buffalo Gap. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Custer | 1,919 | 2 ppb |
| Hermosa-Old System | 420 | 7 ppb |
| Spring Creek Acres | 172 | 1 ppb |
| Hermosa Water Users Association | 108 | 2 ppb |
| Heartland Country Ranchettes | 95 | 1 ppb |
| Rock Ridge Court | 74 | 3 ppb |
| Fairburn Water Association | 65 | 3 ppb |
| North Hermosa Wud | 40 | 1 ppb |
| Paramount Point | 40 | 1 ppb |
Your move
Test your own tap with a certified lab first-draw sample; Buffalo Gap, 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 Buffalo Gap 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.