This years rains most likely killed or did not allow the vegetation to grow for the birds. I would check with the biologist before going regardless. In the past the marsh is usually very packed. If the birds are there you can usually find a spot to hunt but you may not have the space you desire.
Nothing like working birds in and the guys next you to taking passing shots. That's pretty much the case for all the big reservoir duck hunting places in KS, in my experience at least.
Dos is right. Lots of sky-blasting from neighboring hunters. With all the rains, it could be interesting what vegetation is available, as stated. Not to mention, there are a lot of other areas that may hold a lot of water and pull some birds away. Last time I was there, I was on the firing line with a customer shooting geese. I don't like pass shooting but that's what he wanted to do, so we went. It was lights out. Unfortunately, the Whooping Cranes were in the area and snows were off limits. We could've killed a pile of them.
There are some smaller marshes that a guy could hunt, but it is all going to come down to what the water level is when you hunt. If the lakes are still flooded there will be flooded timber hunting available, if you can get the boat in.
Definitely wouldn’t hunt the opener. Would try and hunt during the week as much as possible. The reservoirs in North East KS are holding a huge amount of water still. Almost all the ramps are closed. I’ve had lots of successful scouting trips the last few weeks. I launch my boat right on flooded roadways. It’s going to keep raining though, and if a hurricane comes up into the gulf we will have even more. Anyone have any good primers on hunting timber?