In the 1930s, the mill was removed and the river was isolated from the tides by the construction of locks at both ends.

This changed over the later periods, with the construction of dams and locks for greater navigation improvement.

Much of the ecosystem was formed during the last half-century by the construction of locks and dams.

In 1870, the Oregon State Legislature allocated funds for the construction of locks on the west side of the falls.

Improvements to assist navigation began in 1618, with the construction of sluices and locks.

Navigation on the Don was improved by the construction of cuts and locks, with the lowest lock situated at Stainforth.

The chief technical difficulty was the construction of locks and dams to lift vessels to Lake Winnebago.

The construction of locks (or weirs and dams) on rivers obstructs the passage of fish.

Additional transportation improvements included the construction of several locks and canals to ease river navigation.

Eighteen months later, when the island was completed, construction of locks began for inland navigation and yachts.