Finding potential WetlacultureTM sites in the former Great Black Swamp and the western Lake Erie basin

Abstract

This landscape investigation is focused on finding the most suitable Wetlaculture^TM (wetland + agriculture) restoration sites within the former 6700 km² Great Black Swamp in the western basin of Lake Erie, the shallowest of the Laurentian Great Lakes in North America. The western basin of Lake Erie is now plagued by harmful algal blooms annually due to nutrient discharges primarily from this basin, and water quality was impacted so significantly with toxic cyanobacteria in 2014 that the city of Toledo’s water supply was shut off, affecting hundreds of thousands of residents. This study is aimed to estimate the area of suitable Wetlaculture^TM zones using multi-criteria decision-making GIS model with Analytical Hierarchy Process analysis, especially in agricultural and historic wetland area, with high suitability for flipping farmland to wetlands. A potential indicator GIS model was developed, with various layers of hydrology, soils, and prime farmlands combined, to identify and classify suitable Wetlaculture^TM areas in the now-drained Great Black Swamp region that could mitigate nutrient inflows to Lake Erie. Overall, the estimated area of highly suitable potential Wetlaculture^TM restoration areas in the Western Lake Erie Basin and in the Great Black Swamp area is approximately 1000 km² (4 %) and 800 km² (13 %), respectively, much larger than the 400 km² of wetlands that have been suggested as necessary to control the algal blooms in Lake Erie.