[TapStyx]

I ran the stretch of the Gunnison River last weekend at ~10,000 cfs and heard a very strange sound coming from the either the vicinity of the pontoons of my cat or from the water under the platform. The sound was like "frying bacon" with a popping noise. It wasn't constant at least that I could tell. I looked for bubbles but didn't have a great vantage since the decking on my cat is a poly max mesh deck. My sight was limited and had to pay attention to the river mostly as debris was all over the place and I was moving.

I inflated the tubes and cleaned with sudsy soaping water and couldn't really find a leak of consequence when I got home. The only bubbles I saw came from D-ring patches that overlapped the seam tape. The one or two bubbles came out when I had to really push down hard. Infrequent bubbles seem to be air from the overlapped fabric. Someone told me that with the river cranking the debris and sediment is being churned up and the fine sediment would likely be the cause of that sound. Buzzards what do you think?

 

[washoe99]

I'd guess is was suspended sand rubbing on the tubes which is common at high flows. I head it on the Main Salmon last week but not the clearer Middle Fork


Sent from my iPhone using Mountain Buzz

 

[bigscottone]

Silt and sand for sure. This is super common down here in NM, where when it flows, it flows brown.

 

[Gremlin]

The same gravel that flows into the footbed of your sandal when you wade in the current.

 

[stinginrivers]

Heard it as well on ruby horsethief. Drove me nuts trying to find the hole till I figured out what it was.

The kayakers on our trip showed me a cool trick, you put the paddle blade in the river and put your ear to the shaft or other blade and you can hear the same sound.

 

[fiya79]

This happened to my group too last weekend on the Snake in Wyoming. High water, high silt content and cat tubes. Both boats pulled over to find the leaks. it is a very disconcerting sound.

After some expermenting we decided it was the silt content. In addition to the possiblilty of sand abrasion I felt like the supsension somehow made the water form bigger bubbles, like someone had added a few billion gallons of soap. If I slapped the water with my kayak paddle the bubbles were unusually large and lasted a long time and popped noisily. Put those bubbke next to a big hollow urethane tube and it sounds like a giant vat of boiling oil.


I'm glad I'm not the only dummy out there looking for a leak.

 

[G-wood Todd]

I was chasing the same "leak" on my raft as you described around the same time on the gunison. It was not a welcoming sound and was driving me nuts as I could not pinpoint a leak. Good to know what was causing the sound.

 

[LSB]

MMMMMMMMMMM BACON !!!!

 

[mcfarrel]

Heard it as well on ruby horsethief. Drove me nuts trying to find the hole till I figured out what it was.

The kayakers on our trip showed me a cool trick, you put the paddle blade in the river and put your ear to the shaft or other blade and you can hear the same sound.

I've had the same occur in canoes... I was once told that the noise is created because of the velocity profile of the river being faster at the surface and slower at the bottom of the river due to frictional forces.

The theory was that the current of the river is different at the draft line and the bottom of the boat. The water makes the popping sound you described because when you are floating on the top of the water surface which is faster than the water at the bottom of the boat. This makes the water speed relative to the water surface different than at a the bottom of your boat. Kind of like how an air plain has both ground speed and air speed.

maybe that's it? or maybe i'm totally incorrect but I bought into the BS and sounds like a good explanation.

 

[Jensjustduckie]

Or, you could be hearing the sound of saltation?

Saltation (geology) - Wikipedia, the free encyclopedia

 

[laterwagged]

Or, you could be hearing the sound of saltation?

Saltation (geology) - Wikipedia, the free encyclopedia

What you heard is likely a combination of several things already mentioned. Saltation is a definite possibility, though that term isn't always used when the fluid medium is water.

It will depend greatly on the velocity of the medium (water in this case), the impact medium (your boat or the riverbed), and how well the sediment in question is "sorted" which is a technical term that I won't belabour here.

Saltation in rivers often refers to extreme flow events where large sediment (think bowling ball and larger) are moving downstream without rolling along the bottom, you can often hear them when they hit bottom again - it sounds like thunder and is a solid indication that you have no business on that river at that time.

 

[elkhaven]

I totally aggree, you are simply hearing geology in action, you're hearing the substrate move, rock on rock, pebble sized material to bolders (bowling ball and bigger) rolling down the river. Laterwagged is totally right about saltation. In geology it's typically reserved for wind transported material, but the term can be applied in any medium. It's all energy related but it's likely the medium sized material, gravels to large cobbles that would be saltating in a flood stage river. But with the amount of material moving the only impacts you'll hear will be the big ones. Like he said the bowling ball and bigger stuff, that's rolling down the river. The smaller material is the white noise behind it

 

[Jensjustduckie]

Thanks guys!

I have heard several bowling ball sounds near the take out on Filter Plant on the Poudre this year, kind of unnerving because it sounds like you hit something except you didn't.

 

[laterwagged]

We heard/felt what felt like a lightning strike on the Grand Ronde a couple years ago when it was cranking up near 19K. It shook our tents enough to be visible.

it ended up being a tree in the river that dislodged a major boulder that was banging its way (that the technical term) down the river. Or so we surmised from the new tree that we found in red rock rapid. (Which is no longer there for the record).

 

[TapStyx]

Thanks Buzzards, I knew I could count on ya'll with a great explanation.

 

[BarryDingle]

Where is this Flying bacon cat you speak of

 

[ridecats]

It COULD actually be bacon...