A water resistant backpack is capable of keeping your items dry when there is a rain. However, if you accidentally drop it in a puddle of water, then it cannot keep your things from getting wet. A waterproof dry bag on the other hand, would carry on protecting your valuables no matter the circumstances. The seams of a waterproof bag are not sewn with needlework but welded together so that the water cannot seep through. They are also made of stronger materials. Thus, waterproof bags are more durable and lighter.
No one prefers to carry an enormous bag over their shoulder when they cycle. A light weight waterproof bag would be more suitable for them. In case of a sudden downpour, there is no need to stop the vehicle and dump a rain cover over a waterproof bag. It can also be very valuable to runners.
Certain items work just as well even when they are wet but there are things that must be kept dry under any condition such as outdoor sleeping bag, toilet paper, food etc. Hence, it is essential to have a waterproof bag when you hike.
When you are descending canyons, your backpack would be submerged into the water and it is best to invest on a waterproof bag if you want your things to stay dry.
When you are involved in this activity, there is a high chance your backpack would get wet. So, buy waterproof bags to keep your things safe.
There are lots of choices for you out there for waterproof bags and you can easily choose the right kind of bag which suits your specific needs. Make sure you check our Backpacking, Camping and Outdoor Gear section for more products.