Though the flooding in Grand Forks has been dubbed a once-in-500-years event, experts say the next flood could happen soon -- like next year. University of North Dakota geographer Paul Todhunter says it's more than likely next spring will also bring high waters, if not as bad as last year. Floods, he says, naturally come in clusters: University of North Dakota geographer Paul Todhunter Sun 28-MAY 19:41:15 MPR NewsPro Archive - Fri 04/13/2001