Inundations were an easy method of making an area impassible to enemy Armoured Fighting Vehicles. Along with other natural beach obstacles such as steep cliffs, they would have shortened the area of beach that the artillery and infantry weapons would have to cover in order to produce a co-ordinated belt of fire to break up any attempted enemy landing (e.g. as noted in 125th Brigade War Diary).
From north to south the following inundations were prepared in Suffolk:
Kessingland and Benacre Broad: The sluice at the River Hundred controlled the amount of water in Benacre Broad and at Beach Farm and Church Farm Marshes. The water level was maintained at these marshes at 15” above normal to ensure the ground remained in a permanent boggy condition. It was not possible to flood higher than this otherwise the main road would be flooded. The water level in Benacre Broad was maintained to ensure a permanent anti-tank obstacle.
Southwold: In 1941 arrangements were made to flood Salt Creek by reversing the sluice so water could flow in at high tide but was restricted from flowing out.
Corporation and Dingle Marshes: These were saltwater marshes controlled by a sluice at Walberswick. Water was allowed to flow over the sluice at high tide.
Minsmere Levels: North of the New Cut the marshes were flooded in 1940 as far back as Eastbridge. South of the New Cut, on “Action Stations” the sluice would be raised to flood the country south of the New Cut to Goose Hill and as far west as The Grove. The raising of the sluice would be carried out by employees of the East Suffolk Catchment Board (Robert Smith, Old Rectory, Middleton and Thomas Spindler, No. 1 Heath View, Westleton). The local battalion was to advise when action was required and also to provide a suitable escort.
Church Farm Marshes, Aldeburgh: These marshes, south of Thorpeness and north of Aldeburgh were permanently flooded in places to a depth of 1 ft 6” to 2 ft 6” as far west as the railway but it was not possible to flood to a depth to provide a complete anti-tank obstacle.
Aldeburgh Marshes: two sluices were constructed in the seawall which would be opened on “Action Stations” flooding the marshes to approx 1 ft 6 inches per high tide. This would be done by employees of the East Suffolk Catchment Board and the local battalion was to advise when action was required and also to provide a suitable escort.
Oxley Marshes: On “Stand To” the area from the head of Barthorpe’s Creek at the Dumb-boy Bridge would be flooded between twin banks to form a tank obstacle connecting on the north with an anti-tank ditch east of the Labour Colony (i.e. Hollesley Bay Colony) and on the south with an anti-tank ditch to the east of Buckany Farm. The sluice was to be operated by East Coast Catchment Board employees (Mr V. A. Gooding on weekdays and Mr S.H. Curtis on weekends).
Above: The flooding of Minsmere Levels north of the New Cut clearly show up in this Lufftwaffe Aerial photo
(the dark area in the centre of the photograph).
Battalion commanders were instructed to take the necessary arrangements to prevent sluices required for inundations from being tampered with or sabotaged. This included placing guards during “Stand To”. The Home Guard later took over the duties of guarding sluices and at Aldeburgh Marshes and Dumb-boy Bridge were also trained to operate the sluices.
Local commanders were instructed that no additional inundations could be carried out without the authority of 11 Corps although ditches could be filled after consultation with the local agricultural authorities.
As well as the manipulation of water levels there also existed other marsh areas such as Covehithe and Easton Broads which would form anti-tank obstacles (except in periods of exceptional drought).
15 Div papers, TNA
37 Brigade papers, TNA
45 Brigade papers, TNA
46 Brigade papers, TNA
East Suffolk sub-district papers, TNA