For my "big" pack - food, cooking, tent, tarp, tools - I have an Ostrom Wabakini. Inside it I use an Ostrom pack liner (similar to RBW). Inside the Ostrom liner, I use a contractor trash bag (3 mil) twisted shut and secured with a velcro strap. This serves both as a second layer of waterproofing and to reduce abrasion on the Ostrom liner. For my "personal" pack - sleeping bag, pad, spare clothes, ground sheet (in tent), reading material, spare maps etc.- I use a sealine 70 L pack, also lined with a 3 mil contractor bag sealed as above.
Both of these packs have survived unplanned downstream testing with no water leakage. I've never managed submersion - unless trapped or lashed in a pinned canoe it's not easy to submerge a pack. Even the heaviest pack is generally very buoyant. An 80 litre pack would displace 176 pounds of water - only a really big guy carrying an awful lot of beer could have a pack that heavy.
Once my two-layer waterproofing is in place, I tighten my belt, snug up my suspenders, and head downstream.
Both of these packs have survived unplanned downstream testing with no water leakage. I've never managed submersion - unless trapped or lashed in a pinned canoe it's not easy to submerge a pack. Even the heaviest pack is generally very buoyant. An 80 litre pack would displace 176 pounds of water - only a really big guy carrying an awful lot of beer could have a pack that heavy.
Once my two-layer waterproofing is in place, I tighten my belt, snug up my suspenders, and head downstream.
