WALLA WALLA, Wash. – The Walla Walla District of the U.S. Army Corps of Engineers will open Rooks Park to vehicles for the upcoming recreation season one day earlier than originally planned. The park will open to vehicle traffic on Sunday, March 31, instead of its usual annual seasonal opening date of April 1. Rooks Park is located on Mill Creek Road just east of Walla Walla, Wash.