| AGENCY | MSR/SOI | BOUNDARY MAP |
| Coffee Creek FPD | Adopted 2.18.2020 | |
| Hayfork FPD | Adopted 2.22.23 | |
| Hyampom CSD | Adopted 6.15.2021 | |
| Middle Trinity River Regional Fire Services | Adopted 12.17.2025 | |
| Post Mountain PUD | Adopted 8.15.2023 | |
| Ruth Lake CSD | Adopted 4.19.2022 | |
| Trinity Center CSD | Adopted 2.18.2020 | |
| Trinity County Waterworks District #1 | Adopted 2.18.2025 | |
| Trinity PUD | Adopted 4.20.2021 | |
| Weaverville CSD | Adopted 10.20,2020 | |
| Weaverville Sanitary District | Adopted 8.18,2020 |