Centennial Trail Post Falls, Idaho and Spokane River

Walked from the Avista Island Trailer Park trail head on Lundy Blvd along the river, the path doesn't go very far along the river but it was pretty. Avista Island is across the river from this trail. The concrete bunker was along the path by the river, it looked like there might have been a house down along here at one time, but I don't know what the purpose of the bunker was.
 I then went up to the Centennial Trail at S Elm Road and went back toward Post Falls. Interesting sign posts and history lessons on this leg. I didn't know about Corbin's Ditch, but that finally explains the concrete viaduct I have always wondered about. In 1899, according to the sign a gentleman named DC Corbin formed the "Spokane Valley Irrigation Company and built this concrete "ditch" to bring water to the farms as far away as the Spokane Valley from Post Falls. Neat History!