There are occasions when a dry sack might appeal to a lightweight backpacker, for example when canyoneering, or in extreme wet weather as found in Patagonia, New Zealand and the US Pacific Northwest to name a few locales. But under what conditions can you expect a lightweight dry sack to keep your gear dry? How about if you fall when crossing a river, don't have room in your bivy and leave clothing in a dry sack out in the rain all night, or, as happened to one of our staff in Patagonia, unpack in camp in the evening to find that your pack is holding a couple of inches of water in the bottom - where your sleeping bag is?
Descriptions on manufacturer web sites aren't of much help, only emphasizing that the dry sacks are waterproof. A typical description (from Outdoor Research) is, "This dry sack offers lightweight, compressible protection. The fabric has a waterproof coating and the seams are taped to keep moisture out. A roll-top closure keeps your gear dry and secure." There is no mention of the limit of conditions the bag is expected to keep gear "dry and secure." Performance is caveated by all the manufacturers of lightweight dry sacks I tested (except Outdoor Research) somewhere, at a minimum saying that the bags won't withstand extended submersion, and often that valuable items should be double bagged. Only Granite Gear mentions any caveat on their website, other companies mention the limitations on the packaging or in the instructions inside the package.
I put the lightest dry sacks available from Outdoor Research, Sea to Summit, Granite Gear, Cascade Designs (SealLine), and Pacific Outdoor Equipment through five tests. My objective was to understand the performance limitations of these dry sacks. The test methods and results follow.
- Dry Sacks Tested
- Granite Gear Drysack
- Cascade Designs SealLine Storm Sack
- Outdoor Research HydroLite
- Sea to Summit Ultra-Sil
- Pacific Outdoor Equipment WXtex Pneumo Lightweight
- TABLE: Test Results
- Observations from the Tests
- Roll Tops
- TABLE: Water Weight Gain
- TABLE: Manufacturer Claimed Weight vs. Measured Weight
- TABLE: Weight Comparison for Similar Sized Dry Sacks
- Overall Observations
- TABLE: Plus/Minus
- Recommendations for Consumers
- Recommendations for Manufacturers
# WORDS: 4100
# PHOTOS: 10
# TABLES: 5