High-volume dry bags, like the Sea to Summit Big River Dry Backpack, are a near essential for anyone looking to do longer trips where there’s a real threat of water putting a damper on your festivities. Whether this is headed to the river for a multi-day rafting trip, trekking through canyons, or diving at your nearest coastline- keeping your 
Durability
Strong seams, sturdy components, and reasonable resistance against abrasion are some of the first things we look for in any dry bag. All of these qualities are even more important when you anticipate long carries or keeping your gear dry for multiple-day stretches. Fortunately, we truly loved this version of the Big River with all the usual features you come to expect from Sea to Summit dry bags, plus the added backpack harness system.
We tested the Big River, naturally, by filling it to the brim with things we needed to keep dry in the field. Even when stuffed with a menagerie of pointy and oblong pieces of camping and fishing gear, we didn’t see any signs of stress along the seams or on the main body of the bag. Not much to be surprised about here, but it’s good to know that the basic functions of the bag perform up to Sea to Summit’s expected quality.
Our biggest concern with this pack was the backpack carry system. Convenience carry features like this tend to overpromise and underdeliver when put to the test in the field, but we’re happy to say that we didn’t get this feeling from the Big River Backpack. We’ll touch on this more below, but the carry system feels much less like an afterthought and more like a great addition to a high-volume bag. While we don’t necessarily think it’s indestructible, we felt like our shoulders would give out before the backpack when it comes to durability.
Waterproofing
Sea to Summit employs their standard roll top closure for the Big River Dry Backpack. Between this proven seal and the 420D fabric body, we weren’t too concerned about the overall integrity of the build. What we did question were the places welded to the bag – like around the shoulder straps and daisy chains – it seemed like more potential points of failure compared to simpler bags.
To test the backpack’s waterproof qualities, we gave the Big River Dry Backpack our standard hosedown, with a focus on potential problem areas. Despite the heavy stream of water, the backpack’s outer surface wicked the water away and dried quickly. Everything inside was completely dry, and there was no threat of any outside water getting things wet when taking objects out of the bag.
The backpack straps stayed damp for over an hour after use, but they were not sodden or dripping. The fabric added some cushion but did not hold water, taking into consideration that hiking around with sodden straps could be uncomfortable.
Backpack Carry
It follows that the standout feature of this drybag is the titular backpack carry system. Our overall impression is positive, the backpack carry on this version of the Big River is very central to the build. We appreciate the thought that went into the design, and the feature escapes the usual pitfall of feeling like an afterthought.
While a far cry from a fully-built overnighter, the Big River 50L Dry Backpack has many of the comfort and fit amenities we’d look for in any backpack. The straps are fully adjustable, allowing you to raise or lower the height of the straps to ensure a comfortable fit. The straps also feature load lifters, which help to distribute the weight of your fishing gear or outdoor essentials evenly and reduce pressure on your shoulders.
We were less impressed but do understand why the design choices were made for non-padded chest and waist straps. They help the backpack dry quickly, and stay secure and stable but notably lacked the comfort that we want for hauling weight over any kind of distance. Also, from a carrying perspective, we noted the lack of a backplate. While we understand again that this could hold water and could sacrifice the waterproofing of the bag, without one, there’s no real structure to the bag beyond how you pack it, so plan accordingly.
Overall, the backpack fits comfortably, and we had no issues carrying it fully loaded. However, you may want to be mindful of how much weight you are carrying and what items will be pressed against your back.
Sizes and Other Features
The Big River 50L Dry Backpack is simple and serviceable, with a streamlined build that prevents leaks and keeps its uses pretty specific. What it does offer in the way of a well-built, dry backpack that is comfortable to carry is complemented by a couple of simple amenities like a white liner interior for better visibility along with a combination daisy chain/side handle for tie downs and convenience.
We tested the 50L version and were impressed with how comfortably we could carry all our necessities. Sea to Summit also makes a 75L model if you think your needs merit a bigger bag.
Value
These models run on the upper end of dry bag price ranges because of their distinctive features.
The Sea to Summit Big River Dry Backpack is priced at a premium compared to some other dry packs on the market. However, its high-quality construction, well-designed backpack components, and waterproof qualities may justify the higher price point for those who need a reliable and durable dry backpack for outdoor activities like kayaking, rafting, or camping. As we’ve mentioned several times in this review, we haven’t found any other dry bags with a backpack system that works as well as this one.
Do We Recommend It?
Yes- and we’ve made it an Editor’s Choice! If you’re frequently finding yourself in positions where you need to haul a dry bag back and forth, this model makes a lot of sense. If you are like us and taking trips where you are getting in and out of boats, transporting camera gear through wet and rainy places, or canyoneering, this bag will keep your gear dry, haul your loads, and keep your hands free.
Yes- and we’ve made it an Editor’s Choice! If you’re frequently finding yourself in positions where you need to haul a dry bag back and forth, this model makes a lot of sense. If you are like us and taking trips where you are getting in and out of boats, transporting camera gear through wet and rainy places, or canyoneering, this bag will keep your gear dry, haul your loads, and keep your hands free.
Specs & Features
| Material | 420D nylon build |
|---|---|
| Buckles | Field repair buckle with stainless steel pins |
| Seams | Taped and reinforced seams |
| Attachment points | Hypalon lash loops and plastic tie-down rings |
| Closure | Non-wicking Hypalon roll-top closure |
| Base | Roll-resistant oval base |
| Sizes | Available in sizes 50L or 75L |
