Cascade Locks and Bonneville will switch to new telephone numbers at 12:01 a.m. Sunday, Oct. 17, according to J.B. Mason, manager for Pacific Northwest Bell. On that date, the two telephone offices will be combined into one office in Cascade Locks and long distance calls between the two towns will be eliminated. Existing three-digit customers at Bonneville will be replaced by new seven-digit numbers, all beginning with the prefix “374.” Cascade Locks will add “374” to the present four numbers