James,
I wish it would be so simple as to change a few regulations. But the truth is the regs have nothing to do with it. The Red River flows north so the farther you go north the bigger the river is. Also there are about 10 dams on the Red and during certian times of the year, mainly Fall, catfish tend to move downstream looking for deep water or slack water areas to Winter. What happens as they move down river they go through a dam and can not come back unless there is high water during the time they are moving upriver.
The Red River drains into Lake Winnipeg. A lot of catfish Winter in that big lake, come Spring they make a run upriver and only make it to the first dam and pile up below it.
This also happens with the Walleyes in the Fall. They make a run upriver, coming out of Lake Winnipeg, and will stack up below that dam as they can go no farther.
The Red does have great fishing from Wahpeton all the way to Winnipeg, its just when you drop below the last dam does the fishing improve dramatically. Thats just because the dam is there to block the movement of the fish upriver.
I hope I have explained this good enough for you to understand.
Any other questions, just ask.
Dennis