To understand rivers, we need to be able to get to them so that we can see, smell and touch their waters. Frequent access is especially important: it helps us understand that change is normal.

There are quite a few places along the Speed River in Guelph, Ontario, where you can reach the water. This location near my home is popular. A path leads straight down to the river. Dogs can play in the river, and children can explore the shoreline.

Regular visitors will notice that water levels can change dramatically from day-to-day. Some of this is natural -- a function of the seasons and precipitation. However, many people don't realize how much of the flow in the river is controlled by an upstream reservoir that evens out the flows.