 An island in the Mississippi River near Minnehaha Creek once existed ; the receding St. Anthony Falls divided into two as it passed around the island . The falls in the channel farthest from Minnehaha Creek reached the upstream end of the island first , cutting off water to the west channel and resulting in an " abandoned waterfall " at the north end of the channel . The abandoned west channel is now a grassy cul @-@ de @-@ sac known as the " Deer Pen " . Locating the abandoned waterfall was made difficult in recent years since the Deer Pen was partially filled with tons of fill dirt from nearby construction projects . The lower portion of Minnehaha Creek now flows through a wide and deep channel once belonging to the larger stream that was still receiving glacial runoff . The mouth of Minnehaha Creek where it joins the Mississippi River is the lowest surface point in the city of Minneapolis at 686 ft ( 209 m ) above sea level . 
