Garrison Water Supply, IA
Lead detected, under the action levels
Latest 90th-percentile lead: 1 ppb (monitoring period 2022-2024). 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 Garrison Water Supply
Garrison Water Supply serves about 344 people through 143 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 Benton County, Iowa. EPA system ID: IA0625078; phone on file: 319-551-0551. Ask them for your address in their service line inventory - every system had to publish one by Oct 2024.
Lead results over time
That is down 3 ppb from 4 ppb in the period ending 2021. The highest 90th-percentile result EPA holds for Garrison Water Supply is 8.6 ppb across 3 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2024 | 1 ppb |
| 2021 | 4 ppb |
| 2018 | 8.6 ppb |
How Garrison Water Supply compares
Of the 1,066 Iowa systems with a lead result, the median latest reading is 1.4 ppb; 4 are over 15 ppb right now and 36 have gone over at some point. Garrison Water Supply's 1 ppb sits at the 41st percentile in Iowa and the 53rd nationally (higher means more lead).
Neighbouring systems
16 other systems share Benton County; 7 of them have a higher latest lead result than Garrison Water Supply. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Vinton Municipal Water Dept | 4,938 | 0 (not detected) |
| Belle Plaine Water Dept | 2,380 | 9.8 ppb |
| Atkins Municipal Water Works | 2,056 | 2 ppb |
| Poweshiek Water Association (Cr) | 2,000 | 0.6 ppb |
| Urbana Water Supply | 1,562 | 0 (not detected) |
| Shellsburg Water Supply | 961 | 3.1 ppb |
| Newhall Water Supply | 881 | 2.1 ppb |
| Van Horne Water Works | 779 | 0 (not detected) |
| Blairstown Water Supply | 738 | 0 (not detected) |
| Keystone Water Supply | 599 | 5.9 ppb |
Next steps for Traer, IA
Test your own tap with a certified lab first-draw sample; Traer, IA 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 Garrison Water Supply 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. The action level is dropping - the 10 ppb rule from 2027.