One of the instream uses of waterways is for navigation, and waterways are sometimes characterized in statutes and state constitutions as “common highways” open to all. In the case of man-made waterways such as canals, however, the notion of these channels as “common highways” has often been muddled or lost, as control of such canals has often been turned over to private companies.1 As some of these older canals have become less economically viable as corridors for commercial shipping, however, perceptions of these waterways have begun to change. These waterways are viewed less as privatized artificial conduits and more as public natural space.

When thinking about the concept of protected natural areas, there is often a tendency to consider such protected natural areas in contrast to or in opposition to artificial man-made structures. Similarly, when thinking about the concept of protected natural areas, there can be a tendency to assume that the appropriate location for such areas is geographically remote from the more built-up urban environment.