Barmby Barrage

These boats are on the tidal section of the River Ouse, waiting to enter the River Derwent. 

At the confluence of other rivers this would be a straight-forward matter of waiting for the water levels to rise to a navigable height, but here the Derwent is not free to flow.  Instead it is controlled by Barmby Barrage.

Seen from the Ouse the entrance to the River Derwent looks like this.  Built in 1975 Barmby Barrage stops the saline and sediment-rich tidal waters of the Ouse from contaminating the fresh and clear waters of the Derwent, which, further upstream, is extracted for drinking water.  Another function is flood-control by excluding high levels on the Ouse which sometimes struggles to deal with high volumes of fresh water coming down from the hills north of York, and abnormally high tides. All the water-level calculations are done automatically, with the barrage-keeper on hand to deal with any problems and operation of the lock for boaters.

On the left are the closed gates to the lock-chamber, the opening of which was awaited by the boats in the photograph above.  On the right are the sluices which control the levels between the Ouse and the Derwent.  Between the lock and the sluices is the jetty which juts out 37ft.

The jetty, seen from the Derwent side
(No, it doesn't have a power station on it). 

A recent addition is a “lamprey ladder”, seen here during installation, sloping down into the Ouse.  These eel-like, but not eels, fish need to come in from the sea to breed in fresh water  -  a supply of which from the Derwent flows down the “ladder” and the lampreys in the Ouse sense it and swim up the ladder.  It was installed in 2011, so what the lampreys had been doing since the barrage was installed in 1975 I don’t know.  Nevertheless, they now have an Environment Agency ladder to help them on their way.

Having passed through the barrage's lock boats are on a very different waterway.  Navigation on the Derwent has a complex history  -  the Navigation Act was repealed in 1935, and waterways enthusiasts fought long and hard in the 1970s and 1980s to have the legal right to boat upon the river.  The situation remains unclear - there is no navigation authority, and boats can only cruise as far as Stamford Bridge.

The Dewent, looking upstream
from the barrage's mooring pontoon

On the Derwent the surroundings of the barrage are a well-maintained amenity site with leisure facilities which include course fishing, a bird-watching hide, a wildlife reserve and a picnic area.  There’s also a mooring pontoon for boats waiting for passage through the barrage.  It’s a quiet area with free parking, at the end of the road from Barmby on the Marsh.  We like it.