The Conestogo River has been a blessing and a trial for the Drayton townspeople. In spring spate, the river rises above its banks and much of the community trail disappears under water.

Bunches of grass caught in trees at eye level stand in mute testimony to the power of the normally sluggish river and the volume of water that moves down the valley each spring. The trail follows the floodplain, with much of it on a berm that protects downtown businesses. A good stone dust surface requires regular maintenance to undo the effects of flooding.

Wetlands and riverbanks are probably the most...