Bend’s Lost Cave

A couple years ago, I published a technical article in issue 29 of the Oregon Underground newsletter. It was about Brogan’s mention of a “lost cave” in Bend. It was thick with references and not easy to read. This blog post will take another approach in exploring the possibility of a lost cave in Bend. Phil Brogan, a historian of Bend among other things, wrote about a lost cave in a 1941 issue of the Oregon Journal. Here’s what he had to say:

“In east-side Bend, on or near the old L. D. Wiest property, there is a ‘lost cave.’ When Bend was a pioneer town, this cave had a big opening. Because such an opening was dangerous, it was closed with rocks and carefully covered with dirt, old timers say. And now, not even the old timers know the exact location of the cavern. But occasionally there is heard under the earth dull thuds, probably loose rocks falling from the roof of the lost cave.”

Now there is a tempting morsel! To my knowledge, this single paragraph is the only original documentation of a cave located on the east side of Bend. By the east side of Bend, Brogan is describing the Wiestoria property roughly between NE 2nd Street and NE 12th Street north of Greenwood Ave.  This historic Wiestoria is not to be confused with the new Wiestoria development property at the corner of 8th and Revere, though it does fall squarely inside the historic Wiestoria.

So Brogan says this lost cave is squarely in the center of good ‘ol Bend! Any cave in the vicinity of Wiestoria would be a part of the flow that created Lava River Cave, or a small lava flow that issued from the northwest flank of Pilot Butte. There is a small chance that the cave is related to the fault scarp that runs through Wiestoria, but typically these scarps are oblique-slips, which is to say, they are a combination of fault boundaries moving horizontally and vertically against one another, but it’s uncommon to have the boundaries of these faults shift away from another to leave a gap.

And what’s this about “dull thuds?” I suppose this cave periodically would have a rock dislodge from the ceiling and fall to the floor creating a loud booming noise. No one I’ve spoken with has heard this sound. I personally feel that the occasional “dull thud” being heard is too often an occurrence for a cave that has lasted around 100,000 years. At that rate, I would think the cave would have dismantled itself by now. Perhaps these rocks were falling off from an increase in water erosion caused by the settlement of Bend? In that case, it may be that in the next 100 to 500 years, this cave may open itself up again. If it exists at all.

There are a ton of anecdotal reports on caves on the east side of Bend. Too many to list here, but a few of the noteworthy ones include:

• a cave off Brinson Blvd in the industrial section and since been built over (probably a fault cave) has been noted by two unrelated residents
• a lava tube east of Pilot Butte Middle School near Cliff Dr (estimated to be about 100 feet long) has been noted by two unrelated residents
• a possible cave underneath St. Charles hospital discovered during test drilling or excavation
• a fault cave off Full Moon Dr that was used to funnel treated waste from the old treatment plant (hence the inside joke “Full Moon.”)
• a dubious report of a cave underneath or near the intersection of Penn Ave and NE 12th St, but noted by three unrelated residents
• a bootlegger cave reported south of East Hwy 20 near the intersection of Bear Creek Rd and Purcell Ave (more on this in a later blog)

If you have any information on caves in the city of Bend, especially in the historic Wiestoria area please contact me. Confidentiality is always respected.