The harbor here experiences tides of 28 feet which are not as large as some other parts of the Bay of Fundy but are sufficient to produce some very interesting effects. One of these is the Reversing Falls. These are not really water falls, as one would expect from the name, but are actually great rapids that are produced where the tides from the ocean meet the St. John river. The meeting place is a very narrow and deep underwater canyon that is up to 200 feet deep.
The battle between the river and the ocean is best explained by looking at the tide. When the tide is at a higher level than the river it is able to overcome the river's flow and push the ocean water up river. Salty water has been found at least 70 miles up river. When the tide then turns and flows out to sea its level falls below that of the river which produces a very large flow rate towards the sea. When the tide is the same level as the river's water there is a standoff and there is no flow.
We were fortunate to be able to see all three of these conditions in the same day and they are shown
in the pictures below. The ocean is to the left and the river to the right.
In this set of pictures it is high tide and the water is flowing to the right, up river.
These two pictures shows the same locations at slack water when the tide just balances the river's flow with the effect that there is no flow.
The third set shows what happens when the tide is low and the river adds its flow to the ebbing tide, producing the largest flows.
The "Flower Pots" are pillars of sandstone that have been eroded by the tidal action.
The photos below show them at low tide, when you can walk on the beach and observe
that they are pillars that have been undercut by the tide. During high tide they
appear as small islands with balsam fir and dwarf spruce growing on top, much like a
flower pot would appear. Just another example of what the tidal forces can do.