Willow Grove Mill, DE
Lead reported as not detected
Latest 90th-percentile lead: reported as 0 (not detected) (monitoring period 2023-2023). The federal action level is 15 ppb today and drops to 10 ppb in Nov 2027; EPA's health goal is 0. The latest 90th-percentile result was reported as 0 (not detected at the lab's limit). That says the sampled homes were low, not that your home has no lead service line. Check your utility's service line inventory for your address.
Willow Grove Mill at a glance
Willow Grove Mill serves about 3,090 people through 1,026 service connections, which makes it a small system under EPA's size classes. It is owned by a local government (city, town, county or district) and draws groundwater, in New Castle County, Delaware. EPA system ID: DE0020122; phone on file: 302-275-6072. 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 2022 (0 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Willow Grove Mill is 0 ppb across 2 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2023 | 0 (not detected) |
| 2022 | 0 (not detected) |
Against other Delaware systems
Of the 196 Delaware systems with a lead result, the median latest reading is 0.31 ppb; 1 are over 15 ppb right now and 14 have gone over at some point. Willow Grove Mill's reported as 0 (not detected) sits at the 39th percentile in Delaware and the 33rd nationally (higher means more lead). Systems reporting 0 tie at the bottom, so the rank mostly reflects size among them.
Neighbouring systems
30 other systems share New Castle County; 17 of them have a higher latest lead result than Willow Grove Mill. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Artesian Water Company | 231,114 | 1 ppb |
| Wilmington Water Department | 107,976 | 0 (not detected) |
| Veolia Water Delaware, Inc | 100,495 | 2 ppb |
| Newark Water Department | 40,000 | 1 ppb |
| Middletown Water Department | 17,700 | 0 (not detected) |
| Municipal Services Commission | 5,549 | 0 (not detected) |
| East Ncc District | 5,538 | 0 (not detected) |
| North West Pump District | 4,149 | 0.8 ppb |
| Delaware City Water Department (Awc) | 2,610 | 1 ppb |
| Delaware Correctional Center | 2,000 | 0 (not detected) |
Your move
Look up your address in Willow Grove Mill's service line inventory. If it says lead, galvanized or unknown, test your tap. If your own line is lead, replacing the private side runs about $1,200-$12,300 (EPA average about $4,700). Ask Willow Grove Mill 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. A zero today does not rule out a jump later - the rules are tightening in 2027.