Keystone Ranch, CO
Exceeded the action level in the past
Latest 90th-percentile lead: 6 ppb (monitoring period 2026-2026). 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.
Who runs the water here
Keystone Ranch serves about 670 people through 108 service connections, which makes it a small system under EPA's size classes. It is privately owned and draws groundwater, in Summit County, Colorado. EPA system ID: CO0159065; phone on file: 303-404-8000. They can tell you what your service line is made of and whether they pay to replace it.
Keystone Ranch's lead record
Against the period ending 2025 (5 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Keystone Ranch is 32 ppb across 9 monitoring periods, 1 of them over the 15 ppb action level.
| Period ending | 90th-percentile lead |
|---|---|
| 2026 | 6 ppb |
| 2025 | 5 ppb |
| 2025 | 32 ppb over 15 |
| 2025 | 5 ppb |
| 2021 | 9 ppb |
| 2020 | 9 ppb |
| 2019 | 7 ppb |
| 2018 | 8 ppb |
| 2017 | 9 ppb |
Where this result ranks
Of the 1,025 Colorado systems with a lead result, the median latest reading is 1 ppb; 2 are over 15 ppb right now and 71 have gone over at some point. Keystone Ranch's 6 ppb sits at the 95th percentile in Colorado and the 93rd nationally (higher means more lead).
Neighbouring systems
22 other systems share Summit County; 2 of them have a higher latest lead result than Keystone Ranch. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Breckenridge Town Of | 28,315 | 2 ppb |
| Snake River Wd | 9,900 | 0.9 ppb |
| Silverthorne Town Of | 8,400 | 0 (not detected) |
| Copper Mountain Consolidated Md | 5,785 | 5 ppb |
| Frisco Town Of | 4,495 | 4 ppb |
| Dillon Town Of | 3,254 | 5 ppb |
| Dillon Valley District | 3,063 | 3 ppb |
| Buffalo Mountain Md | 2,650 | 1 ppb |
| East Dillon Wd | 2,501 | 4.2 ppb |
| Mesa Cortina Wsd | 466 | 2 ppb |
What to do in your house
Test your own tap with a certified lab first-draw sample; Keystone, CO 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 Keystone Ranch 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. More in what a past exceedance means today.