Multiple Drivers of Flooding in SW Manitoba

Professor John Pomeroy has contributed to an article in the Winnipeg Free Press which describes how the convergence of changing climatic influences with continuing major efforts to squeeze greater productivity from farmland has resulted in widespread flooding across large areas of south-west Manitoba.

Local livestock farmers see the immediate culprit as being the continued implementation (often illegally) of drainage schemes in upstream areas, primarily by grain producers. While the removal of sloughs in the natural ‘Prairie Pothole’ landscapes adds productive acreage, it also reduces local storage capacity, thereby facilitating runoff and artificially augmenting flows further downstream. The problem is compounded by the damage wrought to soil structure by progressively more intensive and industrial agricultural practices during the past century, which has reduced its ability to hold moisture internally.

This year, these effects are exacerbated by the past winter’s unusually heavy snowpack. Increasing incidence of heavy fall rainfall, and ice crusts resulting from spring rain-on-snow events, have also been found to amplify the overall problem.

The article is available online in its original form, and for download in PDF format.