Thank you for adding a bit of information to the story. Spring of 1969 was my first visit to Riparia WA just a few months after the Union Pacific bridge across the Snake River was removed. I remember standing on the new Camas Prairie line built from Riparia to Central Ferry to gain elevation over Little Goose dam located just east of Riparia. There was a new little depot and a few additional structures built at the west end of the bridge on this new section at Riparia, which also are now long gone except for the concrete slabs. Looking down on the old town site of Riparia from the new line I have no image in my mind of what was left in 1969, most likely nothing. The old UP main track to Hay and on to La Crosse was still active up to 1980 I believe. What I would like to know is did the section from Riparia to Hay remain in service longer than the section from Hay north to la Crosse. My memory says that was the case.
What I remember is seeing a tank car at Hay sometime in the early 1980's but no track north of Hay at that time.