Diamond Springs Water Association, WA
Lead detected, under the action levels
Latest 90th-percentile lead: 3.5 ppb (monitoring period 2014-2016). 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
Diamond Springs Water Association serves about 138 people through 43 service connections, which makes it a very small system under EPA's size classes. It is privately owned and draws groundwater, in King County, Washington. EPA system ID: WA5319215. Ask the utility on your bill for your address in their service line inventory.
Lead results over time
The highest 90th-percentile result EPA holds for Diamond Springs Water Association is 3.5 ppb across 1 monitoring period, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2016 | 3.5 ppb |
Against other Washington systems
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. Diamond Springs Water Association's 3.5 ppb sits at the 85th percentile in Washington and the 85th nationally (higher means more lead).
Neighbouring systems
153 other systems share King County; 18 of them have a higher latest lead result than Diamond Springs Water Association. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Seattle Public Utilities | 1,161,961 | 1.6 ppb |
| Bellevue City Of | 321,349 | - |
| Kent Water Department | 166,421 | 0 (not detected) |
| Redmond Water System City Of | 163,335 | 2 ppb |
| Lakehaven Water And Sewer District | 148,809 | 3.3 ppb |
| Renton City Of | 108,091 | 1.9 ppb |
| Auburn City Of | 107,655 | 2.2 ppb |
| Highline Water District | 100,170 | 1.4 ppb |
| Northshore Utility District | 99,789 | - |
| Sammamish Plateau Water & Sewer | 79,362 | 1.7 ppb |
What to do in your house
Test your own tap with a certified lab first-draw sample; Port Orchard, 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 Diamond Springs Water Association whether it covers that cost before hiring anyone - many utilities now do. Its latest copper 90th percentile is 2481.5 ppb (copper action level 1,300 ppb).
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.