 Most of the 47 people killed in this incident were in Pendleton and Grant counties, according to the National Weather Service.Flooding in the Tygart Valley River basin (a tributary to the Monongahela River) set new records for peak discharge at all five of the long-term unregulated gauging stations in the basin.However, the peaks were not as extreme, relative to the previous peaks of record, as those in the Cheat River and South Branch Potomac River basins.