During flood years such as the 2011 Assiniboine River flood , inlet flows to the Portage Diversion control structure were measured at over . This amount of water would have disastrous effects if left to flood southern Manitoba . During the flood of spring 2011 , the Portage Diversion handled roughly half the flow of Niagara Falls
2011 Assiniboine River flood
2011 Assiniboine River flood
Portage Diversion