There should be no net fishing for any river period . Talk about non selective!
Actually, terminal fisheries are the most selective practice because you're specifically targeting one stock. Fisheries that take place in the ocean, or in the mainstem Lower Fraser River, are not selective because you're intercepting multiple runs of fish at once. You can be targeting runs that are very sustainable, but you can also be catching fish from runs that are almost extinct. Catching fish closer to the spawning ground can also lead to better management because by this point you have a better idea how large the return is, so your margin of error is much smaller when taking fish out of there.
The problem with these two gill nets being used in the lower section of the Vedder Canal is that two stocks are being intercepted. One is the targeted Chilliwack Lake stock which will have 100,000+ fish returning this year, while some Cultus Lake fish, which are endangered, might be intercepted because they are already moving through the system.
The better alternative is to have the netting taking place further upstream above the hatchery up to the lake, where pretty much all of the fish are Chilliwack Lake stock. It is also taking place outside of the recreational fishing boundary so user conflicts are unlikely.