Detroit Lakes Carnival To Open TonightDETROIT LAKES—More than 25,000 visitors arc expected here this weekend for the 20th annual Northwest Water carnival.The show will open tonight with a street dance and a torchlight parade.Sunday a parade featuring 15 bands and 100 uniLs will be staged along with a $250 fishing derby and the Miss Northwest contest.Nancy Louise Jenson, 19, Fergus Falls, Minn., is Lhe reigning queen. She also is a princess of the Minneapolis Aquatennial.