Northstar Subdivision, ID
Lead detected, under the action levels
Latest 90th-percentile lead: 3 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.
Northstar Subdivision at a glance
Northstar Subdivision serves about 50 people through 16 service connections, which makes it a very small system under EPA's size classes. It is privately owned and draws groundwater, in Canyon County, Idaho. EPA system ID: ID3140278; phone on file: 208-283-0237. They can tell you what your service line is made of and whether they pay to replace it.
Northstar Subdivision's lead record
That is up 3 ppb from 0 ppb in the period ending 2024. The highest 90th-percentile result EPA holds for Northstar Subdivision is 3 ppb across 3 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 3 ppb |
| 2024 | 0 (not detected) |
| 2023 | 0 (not detected) |
How Northstar Subdivision compares
Of the 763 Idaho systems with a lead result, the median latest reading is 1 ppb; 3 are over 15 ppb right now and 46 have gone over at some point. Northstar Subdivision's 3 ppb sits at the 76th percentile in Idaho and the 81st nationally (higher means more lead).
Other water systems in Canyon County
82 other systems share Canyon County; 16 of them have a higher latest lead result than Northstar Subdivision. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Nampa City Of | 100,200 | 1 ppb |
| Caldwell City Of | 78,740 | 0 (not detected) |
| Middleton City Of | 13,190 | 2 ppb |
| Parma City Of | 2,250 | 1 ppb |
| Wilder City Of | 1,690 | 5 ppb |
| Caldwell Housing Authority | 1,100 | 9 ppb |
| Greenleaf City Of | 846 | 2 ppb |
| Melba City Of | 648 | 3 ppb |
| Notus City Of | 539 | 2 ppb |
| Shalimar Subd | 370 | 1 ppb |
What to do in your house
Test your own tap with a certified lab first-draw sample; Nampa, ID 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 Northstar 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. Why sampled homes are the worst-case ones is in the guide to reading the number. The action level is dropping - the 10 ppb rule from 2027.