White Rock, MD
Exceeded the action level in the past
Latest 90th-percentile lead: reported as 0 (not detected) (monitoring period 2024-2024). 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 White Rock
White Rock serves about 256 people through 95 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 Frederick County, Maryland. EPA system ID: MD0100026; phone on file: 301-600-3409. Ask them for your address in their service line inventory - every system had to publish one by Oct 2024.
White Rock's lead record
That is down 11 ppb from 11 ppb in the period ending 2024. The highest 90th-percentile result EPA holds for White Rock is 17.3 ppb across 6 monitoring periods, 1 of them over the 15 ppb action level.
| Period ending | 90th-percentile lead |
|---|---|
| 2024 | 0 (not detected) |
| 2024 | 11 ppb over 10 |
| 2022 | 2 ppb |
| 2021 | 17.3 ppb over 15 |
| 2021 | 7 ppb |
| 2017 | 2 ppb |
How White Rock compares
Of the 437 Maryland systems with a lead result, the median latest reading is 0 ppb; 3 are over 15 ppb right now and 21 have gone over at some point. White Rock's reported as 0 (not detected) sits at the 25th percentile in Maryland and the 17th nationally (higher means more lead). Systems reporting 0 tie at the bottom, so the rank mostly reflects size among them.
Neighbouring systems
27 other systems share Frederick County; 12 of them have a higher latest lead result than White Rock. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| New Design - Frederick County | 74,911 | 3 ppb |
| City Of Frederick | 54,000 | 1.1 ppb |
| Town Of Walkersville | 8,440 | 0 (not detected) |
| Fort Detrick | 7,900 | 0 (not detected) |
| City Of Brunswick | 7,312 | 1 ppb |
| Town Of Thurmont | 6,200 | 4 ppb |
| Town Of Middletown | 5,132 | - |
| Town Of Emmitsburg | 2,921 | 0 (not detected) |
| Mount Saint Marys University | 2,700 | 0 (not detected) |
| Fountaindale South | 2,610 | 1 ppb |
What to do in your house
Test your own tap with a certified lab first-draw sample; Frederick, MD 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 White Rock 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. Why an old exceedance still matters: over the limit before, under it now.