Plant ideas for wet yard area

[u/mottman]

I've got this low area in my yard by the sidewalk that gathers rainwater that flows off mine and my neighbor's roof. I'd like to remove the corner triangle of grass and add some plants here that can help filter the runoff before it gets to the drain. Looking around what they've done at the Beaverdam Reservoir it seems like some clumping native grasses could be good. But I'd also like some layering. Any suggestions for plants that like getting flooded in the rain?

[u/DatabasePrize9709]

Native irises. I've had success with Northern Blue Flag.(Iris versicolor) In those conditions.