Green Tank Irr District 11, WA
Lead detected, under the action levels
Latest 90th-percentile lead: 0.6 ppb (monitoring period 2021-2023). 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.
Who runs the water here
Green Tank Irr District 11 serves about 553 people through 196 service connections, which makes it a small system under EPA's size classes. It is owned by a local government (city, town, county or district) and draws groundwater, in Walla Walla County, Washington. EPA system ID: WA5329550. Ask the utility on your bill for your address in their service line inventory.
Green Tank Irr District 11's lead record
Against the period ending 2020 (0.4 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Green Tank Irr District 11 is 0.9 ppb across 3 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2023 | 0.6 ppb |
| 2020 | 0.4 ppb |
| 2017 | 0.9 ppb |
How Green Tank Irr District 11 compares
Of the 2,218 Washington systems with a lead result, the median latest reading is 1 ppb; 18 are over 15 ppb right now and 62 have gone over at some point. Green Tank Irr District 11's 0.6 ppb sits at the 41st percentile in Washington and the 45th nationally (higher means more lead).
Neighbouring systems
32 other systems share Walla Walla County; 15 of them have a higher latest lead result than Green Tank Irr District 11. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Walla Walla Water Division | 42,959 | 4.4 ppb |
| College Place Water Dept | 8,147 | 2.1 ppb |
| Snake River Housing Water System | 3,036 | 0 (not detected) |
| Waitsburg City Of | 1,817 | 1.7 ppb |
| Consolidated Irrigation Dist 14 | 1,555 | 0 (not detected) |
| Walla Walla University | 1,273 | 0 (not detected) |
| Valle Lindo Homes | 787 | 0 (not detected) |
| Veterans Affair Med Ctr Dept Of | 785 | 1 ppb |
| Great Basin Water Burbank | 656 | 0 (not detected) |
| Burbank Irrigation District 4 | 527 | 0 (not detected) |
Next steps for Walla Walla, WA
Test your own tap with a certified lab first-draw sample; Walla Walla, WA 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 Green Tank Irr District 11 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.