• Whitewater Guidebook
  • By State
    • Idaho
    • Oregon
    • Utah
    • Washington
    • California
    • Colorado
    • West Virginia
    • Bhutan
  • Bucket List
    • Middle Fork of the Salmon River
    • Illinois River
    • Grand Canyon of the Colorado River
    • Futaleufu River
    • Rogue River
    • Selway River
    • Tuolumne River
    • Alsek River
    • Zambezi River
    • Forks of the Kern
  • Gear Garage
    • Gear Garage YouTube Channel
    • Gear Garage Live Show
    • Ask A Question
    • Best Practices Questionnaire
    • Interesting Articles
  • Blog
    • Gear Reviews
    • Pro Tips
    • Events
    • Trip Reports
  • About Us

Cobra Oar Locks & Undercut Rocks | Gear Garage Live Show

Courtney Sweeney / Wednesday, May 27, 2026

Gear Garage Live Show
Gear Garage Live Show
Cobra Oar Locks & Undercut Rocks | Gear Garage Live Show
Loading
00:00 / 00:50:31
Apple Podcasts Google Podcasts Spotify YouTube
RSS Feed

Subscribe: Apple Podcasts | Google Podcasts | Spotify | YouTube

Cobra Oar Locks & Undercut Rocks | Gear Garage Live Show

This podcast is the audio version of the Gear Garage live show, where Zach covers whitewater rafting, river safety, gear, and answers viewer questions. In this episode, Zach discusses the dangers of undercut rocks and addresses a question about a 14-foot Star raft and calculating oar length.


Episode Summary

Zach begins the show by highlighting that this episode will focus on answering user questions and revisiting a video from Bedrock on the Grand Canyon. The main technical segment covers a question regarding undercut rocks and what happens when a swimmer encounters them. He notes that hazards like nasty ledge holes, weirs, trees, and sieves are also major concerns. To look at specific statistics, Zach pulls up the American Whitewater accident database to review trends regarding fatalities, highlighting that "flush drowning" represents about 19% of recorded fatalities.

The second user question comes from a viewer who purchased a 14-foot PVC Star raft from NRS for $600 and wants to know if they wasted their money, alongside asking for the best oar length for a 66-inch wide boat. Zach reassures the viewer that $600 is an incredible price for a raft, making it a very smart financial choice even though PVC boats might not have the absolute best performance or last forever. Regarding oar length, Zach reiterates his standard formula: measure the exact distance between the oar locks and multiply by 1.63. Boaters can then add or subtract half a foot depending on personal preferences like tube size, height, or shoulder width.


Key Questions and Discussion Points

  • Topic: Undercut Rocks. What exactly happens when a person swims into an undercut rock, and can they get pinned like a boat?
  • Topic: Boat Value. Is buying a $600 PVC Star raft directly from NRS a waste of money?
  • Topic: Sizing Math. Does the overall width of a raft dictate your oar length, or does it strictly depend on the distance between the oar locks?

Connect with Zach

  • Instagram
  • YouTube

Zach Collier is the owner of Northwest Rafting Company and an International Rafting Federation Rafting Instructor. He has decades of river guiding and expedition experience across the American West and internationally, specializing in technical rowing and professional guide training.

Author

Courtney Sweeney

Courtney Sweeney grew up in Texas, and has spent the last decade living in different areas of the Rocky Mountains and on the West coast. She enjoys both melted and frozen water, rafting in the summer and skiing in the winter.

Connect with Courtney: 

  • YouTube
 
 

Supported By

Sawyer

Cascade River Gear

Maravia Rafts

River Hardware

NWRC Whitewater Education & Safety Training

Affiliate Links: We receive a commission when you click some of the links on this page and purchase items through Amazon.


Disclaimer: River conditions, obstacles, and rapids can vary for a variety of reasons. Please combine this general information with good judgment and your own river reading skills.


© 2026 Whitewater Guidebook