| Business | Phone |
| Cortright & Seibold 411 S Oregon St, Yreka 96097 | (530) 842-7121 |
| D H Engineering Po Box 1775, Yreka 96097 | (530) 938-1774 |
| James G Bray Civil Engineering 220 Butte St, Yreka 96097 | (530) 842-6813 |
| Piemme & Bryan Inc Engineering 329 W Miner St, Yreka 96097 | (530) 842-4367 |
| Schlumpberger Engineering 409 N Main St, Yreka 96097 | (530) 842-2377 |