There were originally thirteen locks and thirteen staunches (also known as flash locks) along the river and these were entirely constructed form timber. A distinguishing feature of the locks was the lintel that prevented the locks from collapsing inwards. This was almost unique to the Stour and has therefore been used in the River Stour Trust logo as well as being the name of our bi-annual journal, the Lock Lintel.
The early designs of staunches or flash locks had a single gate that upon opening would release a sudden surge of water. Boats moving downstream would wait above the lock until the gate was opened and a ‘flash’ of water carried the boats with it. Later designs comprised two sets of lock gates and a central chamber. Craft enter the chamber and water is released either from or into the central chamber. This brings craft to the same level as the water beyond the second pair of gates to continue passage along the river.
The River Stour Trust seeks to reinstate the locks along the river to enable through navigation. We have successfully restored the locks at Dedham, Flatford and Great Cornard whilst the restoration of Stratford St Mary Lock is our current major project.
Download lock operation guides by clicking on the links below:
DEDHAM LOCK
In 1990 the Environment Agency decided to utilise both Dedham and Flatford Locks for flood control purposes and a tilting weir was inserted into the floor of each lock. At the same time, the River Stour Trust carried out improvement works to the lock gates that enabled the lock to be re-opened for navigational use. The unique paddle gear and gates are replicas of the original design.
FLATFORD LOCK
The River Stour Trust restored Flatford Lock which involved removing tons of mud and silt from the chamber and making the gates watertight. It was opened on Easter Day in 1975 by Lord Greenwood of Rossendale who was a President of the Trust at that time. In 1990, the Environment Agency decided to utilise both Flatford and Dedham Locks for flood control purposes and a tilting weir was inserted into the floor of each lock. By this time, the lock gates were in a poor condition once again and a national appeal successfully attracted sponsorship for the works and new lock gates were installed in 1991. Lintels were also added to maintain a traditional appearance. It was officially re-opened in 1992 by John Constable, a descendant of the well known painter and a President of the Trust at that time.
GREAT CORNARD LOCK
The lock had become derelict in the 1920s and an automatic weir was built on its site. The River Stour Trust was responsible for the construction of a new lock adjacent to the site of the original lock. The new lock has a chamber constructed from concrete and brick whilst the gates are steel.
The addition of the wooden lintels was not structurally necessary but retained the traditional and unique design element of the original lock. The lock was formally opened in September 1997 and restored passage between Sudbury in Suffolk and Great Henny in Essex. It was the first new lock on the river for over 200 years and the first completed Millennium project in East Anglia.
STRATFORD ST MARY LOCK
The restoration of this lock will follow the successful restoration of the locks at Flatford, Dedham and Great Cornard; and open a further three miles of navigation along the River Stour. In Victorian times, and until the late 1950s, a boat hire station existed in the lock cut demonstrating that the river has been used recreationally for many years.
The environmentally sensitive nature of the site means we can only work there during a few summer months each year.
Click here for more information about our working parties.