Northwood First Subdivision, SD
Lead detected, under the action levels
Latest 90th-percentile lead: 1 ppb (monitoring period 2025-2025). 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 Northwood First Subdivision
Northwood First Subdivision serves about 90 people through 39 service connections, which makes it a very small system under EPA's size classes. It is privately owned and draws surface water, in Brown County, South Dakota. EPA system ID: SD4602342; phone on file: 6052257924. They can tell you what your service line is made of and whether they pay to replace it.
Northwood First Subdivision's lead record
That is down 2 ppb from 3 ppb in the period ending 2022. The highest 90th-percentile result EPA holds for Northwood First Subdivision is 3 ppb across 4 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 1 ppb |
| 2022 | 3 ppb |
| 2019 | 2 ppb |
| 2016 | 3 ppb |
Against other South Dakota systems
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. Northwood First Subdivision's 1 ppb sits at the 18th percentile in South Dakota and the 51st nationally (higher means more lead).
Neighbouring systems
19 other systems share Brown County; 9 of them have a higher latest lead result than Northwood First Subdivision. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Aberdeen | 27,989 | 3 ppb |
| Groton | 1,380 | 3 ppb |
| Warner | 485 | 1 ppb |
| Lakeside Estates | 460 | 1 ppb |
| Country Village Park | 340 | 1 ppb |
| Prairiewood Property Owners | 300 | 1 ppb |
| Frederick | 215 | 2 ppb |
| Hecla | 200 | 2 ppb |
| Jobee Acres | 108 | 2 ppb |
| Claremont | 108 | 6 ppb |
What to do in your house
Test your own tap with a certified lab first-draw sample; Aberdeen, 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 Northwood First Subdivision 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. The lead result guide covers how utilities pick the homes they sample. Systems that went over once often dip back under; here is what that means.