Here is a plant that enjoys the wet, the Stream Lily, Helmholtzia glaberrima from Australia. It has the added advantage of enjoying shade as well. They will stand surprisingly dark areas, which are usually very hard to grow plants in. Some people try Clivias in this situation.
In shade the slightly flax-like plant will grow to about 1.5metres high though I have seen a photo of an impressive one nearly two metres high. In full sun they are much smaller. They grow naturally alongside and even in the water of streams along the eastern edge of Australia from Melbourne to north of Brisbane.
They can stand light frost and will survive droughts without water but do suffer in the dry times. They make good tub plants for that shady space.
Habit is similar to Dietes robinsoniana. Leaves are sword-like, stand in upright fans and have an interesting difference of being dark green on one side and light green on the other. Flowers, which appear from late September to January, are small, pink to white, in huge numbers on conical heads and last well as a cut flower. The leaves should also last well when cut.
This plant is still relatively new to the New Zealand scene and is not cheap to buy but it is a plant well worth trying