Left Hand Wd, CO
Lead detected, under the action levels
Latest 90th-percentile lead: 1 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. 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.
Left Hand Wd at a glance
Left Hand Wd serves about 20,280 people through 7,769 service connections, which makes it a large system under EPA's size classes. It is owned by a local government (city, town, county or district) and draws surface water, in Boulder County, Colorado. EPA system ID: CO0107471; phone on file: 303-530-4200. They can tell you what your service line is made of and whether they pay to replace it.
Every lead result on file
Against the period ending 2021 (2 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Left Hand Wd is 2 ppb across 8 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 1 ppb |
| 2021 | 2 ppb |
| 2020 | 1 ppb |
| 2019 | 0.9 ppb |
| 2018 | 1 ppb |
| 2017 | 1 ppb |
| 2016 | 2 ppb |
| 2016 | 1.7 ppb |
How Left Hand Wd compares
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. Left Hand Wd's 1 ppb sits at the 56th percentile in Colorado and the 55th nationally (higher means more lead).
Neighbouring systems
39 other systems share Boulder County; 13 of them have a higher latest lead result than Left Hand Wd. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Boulder City Of | 166,080 | 2 ppb |
| Longmont City Of | 104,178 | 1.6 ppb |
| Erie Town Of | 47,444 | 2.6 ppb |
| Lafayette City Of | 28,700 | 2 ppb |
| Louisville City Of | 20,975 | 0 (not detected) |
| Superior Md No 1 | 17,900 | 0 (not detected) |
| Longs Peak Wd | 3,200 | 2 ppb |
| Lyons Town Of | 2,990 | 0 (not detected) |
| Nederland Town Of | 2,406 | 1 ppb |
| Boulder Meadows Mhp | 1,657 | 0 (not detected) |
What to do in your house
Test your own tap with a certified lab first-draw sample; Niwot, 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 Left Hand Wd 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. What a 90th-percentile result does and does not tell you: how to read a lead result. The action level is dropping - the 10 ppb rule from 2027.