(1) The commission shall adopt rules defining geographical boundaries of the following Columbia river tributaries and sloughs:

(a) Washougal river;

(b) Camas slough;

(c) Lewis river;

(d) Kalama river;

(e) Cowlitz river;

(f) Elokomin river;

(g) Elokomin sloughs;

(h) Skamokawa sloughs;

(i) Grays river;

(j) Deep river;

(k) Grays bay.

(2) The commission may authorize commercial net fishing for salmon in the tributaries and sloughs from September 1st to November 30th only, if the time, areas, and level of effort are regulated in order to maximize the recreational fishing opportunity while minimizing excess returns of fish to hatcheries. The commission shall not authorize commercial net fishing if a significant catch of steelhead would occur.