Riverine wetlands upstream of towns store floodwater and can reduce downstream flood levels. Flooding of areas adjacent to streams and rivers is a natural occurrence that has led to the development of fascinatiang ecosystems. Colonization of the US has led to the construction of levys and floodwalls to prevent flooding. Because wetlands receive floodwater from rivers and streams they can remove suspended sediments and pollutants from the water before it flows back into the rivers. Less turbid and polluted water can benifit aquatic organisms and improve the aesthetics of downstream ecosystems.
Many school systems have wetland sites used to educate students.
The above is just a small example of the value wetlands provide society.