Tri-City Water District #45, WA
Exceeded the action level in the past
Latest 90th-percentile lead: 4.4 ppb (monitoring period 2023-2025). The federal action level is 15 ppb today and drops to 10 ppb in Nov 2027; EPA's health goal is 0. The latest result is under the action level, but this system has gone over 15 ppb before. Lead comes from pipes, not the source water, so a home with a lead service line can still be exposed. Test your own tap.
About Tri-City Water District #45
Tri-City Water District #45 serves about 300 people through 108 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, Washington. EPA system ID: WA5389400. Ask the utility on your bill for your address in their service line inventory.
Tri-City Water District #45's lead record
That is down 33.7 ppb from 38.1 ppb in the period ending 2021. The highest 90th-percentile result EPA holds for Tri-City Water District #45 is 38.1 ppb across 3 monitoring periods, 1 of them over the 15 ppb action level.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 4.4 ppb |
| 2021 | 38.1 ppb over 15 |
| 2018 | 1 ppb |
How Tri-City Water District #45 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. Tri-City Water District #45's 4.4 ppb sits at the 89th percentile in Washington and the 89th nationally (higher means more lead).
Neighbouring systems
42 other systems share Benton County; 1 of them has a higher latest lead result than Tri-City Water District #45. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Kennewick City Of | 118,164 | 0 (not detected) |
| Richland City Of | 106,499 | 2.4 ppb |
| West Richland City Of | 21,231 | 0 (not detected) |
| Prosser City Of | 8,030 | 0 (not detected) |
| Benton City Water | 5,626 | 0 (not detected) |
| Badger Mountain Irrigation District | 2,331 | 2.8 ppb |
| Summit View Water System | 1,869 | 0 (not detected) |
| Bc Water Co | 1,262 | 0 (not detected) |
| Community Sewer And Water District | 1,200 | 0 (not detected) |
| Oasis Water Corporation | 556 | 0 (not detected) |
Your move
Test your own tap with a certified lab first-draw sample; Kennewick, 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 Tri-City Water District #45 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. Why an old exceedance still matters: over the limit before, under it now.