I'm not sure that you still need the answer, but the baffle curtains are not real sturdy. Environetics will tell you they last forever. They even use our company in their brochure. But what I've seen of our flexible baffles is that they're poor at any place where you're changing direction of the water. This includes entrances, if the influent is perpendicular to the baffle, and ends where the water needs to turn 180 degrees. Pressures that seem negligible in any other case balloon and stretch these baffles. Eventually, this stretching finds a weak spot and things start popping loose.
Another very worrisome case is filling the basin. If the operators turn loose a slug of water into an empty basin, there's no way to avoid unbalanced forces on the baffles.
I've designed several of these systems. I armor (using block or concrete) all turns and entrances for 30 ft. or so. I run the flexible baffle material between these hardened walls. I also add a six inch concrete curb at the base to mitigate some of the filling forces. And if possible, I make sure there's gaps at the base and edges to relieve some of the pressures.
