| Naics index | Naics index description |
|---|---|
| 221210 | Natural gas distribution with transmission |
| 221210 | Natural gas marketers |
| 221310 | Canal, irrigation |
| 221310 | Filtration plant, water |
| 221310 | Impounding reservoirs, irrigation |
| 221310 | Irrigation system operation |
| 221310 | Water distribution (except irrigation) |
| 221310 | Water distribution for irrigation |
| 221310 | Water filtration plant operation |
| 221310 | Water supply systems |