Diablo Wtr Sys-Seattle City Light, WA
Above the federal action level
Latest 90th-percentile lead: 15.5 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. In the most recent monitoring period, more than 10% of the sampled homes measured above 15 ppb. Use a filter certified to NSF/ANSI 53 for lead for drinking and cooking now, and test your own tap.
Diablo Wtr Sys-Seattle City Light at a glance
Diablo Wtr Sys-Seattle City Light serves about 53 people through 41 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 Whatcom County, Washington. EPA system ID: WA5319200. Ask the utility on your bill for your address in their service line inventory.
Every lead result on file
Against the period ending 2021 (14.5 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Diablo Wtr Sys-Seattle City Light is 15.5 ppb across 3 monitoring periods, 1 of them over the 15 ppb action level.
| Period ending | 90th-percentile lead |
|---|---|
| 2024 | 15.5 ppb over 15 |
| 2021 | 14.5 ppb over 10 |
| 2018 | 4.5 ppb |
Where this result ranks
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. Diablo Wtr Sys-Seattle City Light's 15.5 ppb sits at the 99th percentile in Washington and the 99th nationally (higher means more lead).
Other water systems in Whatcom County
100 other systems share Whatcom County; 0 of them have a higher latest lead result than Diablo Wtr Sys-Seattle City Light. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Bellingham-Water Division City Of | 141,127 | 3.4 ppb |
| Lynden Water Department | 20,062 | 2.3 ppb |
| Ferndale | 19,305 | 5.6 ppb |
| Lwwsd - South Shore Water System | 10,028 | 4.2 ppb |
| Birch Bay Water & Sewer District | 9,046 | 1.8 ppb |
| Blaine City Of | 6,800 | 1.6 ppb |
| Everson City Of | 3,893 | 2.1 ppb |
| Columbia Valley Water District | 2,648 | 1.5 ppb |
| Nooksack Water Dept | 2,427 | 0 (not detected) |
| Glacier Water District | 2,383 | 1.1 ppb |
Your move
Use a filter certified to NSF/ANSI 53 for lead on the tap you drink and cook from, now, before you test. Then test your own tap. If your own line is lead, replacing the private side runs about $1,200-$12,300 (EPA average about $4,700). Ask Diablo Wtr Sys-Seattle City Light 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. Size matters more than most people expect: small vs large water systems.