Ecosystem services provided by floodplains include removal of nitrogen, phosphorus, and sediments, and sequestration of carbon. Effectiveness of floodplains in providing these services is dependent on the extent and location of connection between floodplain and river. Tributary loading of sediments, nitrogen and phosphorus to the Upper Mississippi River contribute to the development of river and coastal eutrophication as well as hypoxic conditions in the Gulf of Mexico. Recent research has shown that management of river connectivity of channels to floodplains is an effective mitigation strategy to remove nutrients, sediment, and carbon from river flows. The confluence of the Maquoketa and Mississippi Rivers is a unique site because: 1) the Maquoketa River carries some of the highest documented sediment and nutrient loads in the Upper Mississippi River (Garrett 2013, Robertson et al 2009); 2) the delta at the confluence with the Mississippi River is heavily managed by a State-Federai-NGO partnership and includes several Habitat Rehabilitation Projects designed to enhance fish and wildlife production and recreational access; 3) a recent nonreparable break in the levy near this confluence has provided an unprecedented opportunity to quantify the biophysical outcomes of increased river-floodplain connectivity; and 4) a new Federai-State-NGO collaboration focused on this site has already produced highly collaborative and productive interactions focused on evaluating the impact of the increased connectivity on numerous ecosystem services, including water quality improvement, flood control, and fish and wildlife productivity and biodiversity enhancement. Further, this site appears to be an ideal test-bed for scaling-up of ecosystem service benefits associated with increased floodplain connectivity to other deltaic sites in the Upper Mississippi River.
