Windward Knoll Mhp, MD
Exceeded the action level in the past
Latest 90th-percentile lead: 1.5 ppb (monitoring period 2025-2025). 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
Windward Knoll Mhp serves about 208 people through 155 service connections, which makes it a very small system under EPA's size classes. It is privately owned and draws groundwater, in Hillsborough County, Maryland. EPA system ID: FL6291988; phone on file: 202-838-6471. Ask them for your address in their service line inventory - every system had to publish one by Oct 2024.
Every lead result on file
Against the period ending 2024 (1.6 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Windward Knoll Mhp is 21 ppb across 6 monitoring periods, 1 of them over the 15 ppb action level.
| Period ending | 90th-percentile lead |
|---|---|
| 2025 | 1.5 ppb |
| 2024 | 1.6 ppb |
| 2023 | 2 ppb |
| 2023 | 2 ppb |
| 2022 | 21 ppb over 15 |
| 2018 | 10.7 ppb over 10 |
Where this result ranks
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. Windward Knoll Mhp's 1.5 ppb sits at the 67th percentile in Maryland and the 63rd nationally (higher means more lead).
Other water systems in Hillsborough County
1 other system shares Hillsborough County; 0 of them have a higher latest lead result than Windward Knoll Mhp. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| The Oaks Of Thonotosassa Mhp | 330 | 0.1 ppb |
What to do in your house
Test your own tap with a certified lab first-draw sample; Potomac, 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 Windward Knoll Mhp 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.