Most "dry bags" have a stiffener strip along the closing edge. Cut off the buckles and you have a lightweight, firm edged bag for getting water from a shallow stream. Having said that, I also use the bottom of a Platy bag as a water scoop (I cut it at the narrow "waist" area). It's plenty stiff enough to allow water to flow in. I like that my fingers don't get dunked in the water on cold days!