Royal Oaks Mhp, IL
Lead reported as not detected
Latest 90th-percentile lead: reported as 0 (not detected) (monitoring period 2024-2026). The federal action level is 15 ppb today and drops to 10 ppb in Nov 2027; EPA's health goal is 0. The latest 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.
About Royal Oaks Mhp
Royal Oaks Mhp serves about 170 people through 65 service connections, which makes it a very small system under EPA's size classes. It is privately owned and draws groundwater, in Mchenry County, Illinois. EPA system ID: IL1115145; phone on file: 312-857-7777. They can tell you what your service line is made of and whether they pay to replace it.
Lead results over time
That is down 5.2 ppb from 5.2 ppb in the period ending 2023. The highest 90th-percentile result EPA holds for Royal Oaks Mhp is 5.2 ppb across 4 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2026 | 0 (not detected) |
| 2023 | 5.2 ppb |
| 2020 | 3.9 ppb |
| 2017 | 3.4 ppb |
How Royal Oaks Mhp compares
Of the 1,744 Illinois systems with a lead result, the median latest reading is 0 ppb; 22 are over 15 ppb right now and 152 have gone over at some point. Royal Oaks Mhp's reported as 0 (not detected) sits at the 7th percentile in Illinois and the 14th nationally (higher means more lead). Systems reporting 0 tie at the bottom, so the rank mostly reflects size among them.
Other water systems in Mchenry County
31 other systems share Mchenry County; 20 of them have a higher latest lead result than Royal Oaks Mhp. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Crystal Lake | 40,661 | 6.8 ppb |
| Algonquin | 30,700 | 1.96 ppb |
| Lake In The Hills | 28,661 | 0 (not detected) |
| Huntley | 28,495 | 1.1 ppb |
| Woodstock | 25,630 | 1.5 ppb |
| Mchenry | 22,335 | 6.7 ppb |
| Cary | 17,826 | 1.7 ppb |
| Harvard | 9,469 | 7.1 ppb |
| Il American-Whispering Hills | 8,300 | 0 (not detected) |
| Marengo | 7,572 | 0 (not detected) |
Next steps for Chicago, IL
Look up your address in Royal Oaks Mhp'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 Royal Oaks 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. Small systems behave differently: why small systems go over more often.