I've fished jigs in the Fraser but found it difficult to fish them successufully from shore. It's hard to keep the jig at a good depth and with limited visibility it's hard for the fish to key on them and strike if you have too much jigging movement. You can still catch them this way though, as pointed out by cutthroat 22.
If you have a boat, it's much easier as you keep the cast distance to a minimum and focus on keeping the jig at a level depth as it goes down current. Very small jigging motion (two to four inches) gives the fish a good opportunity to grab it.