Monument record LKD 034 - Lackford double lock, River Lark Navigation

Double lock on River Lark Navigation. The Lark Navigation was constructed between 1699 and 1715 (between Mildenhall and Fornham, and extended to Bury about 1715)(S1, S2). For various Acts relating to the Lark Navigation see 'River Lark Acts 1700-1817 in Suffolk Recod Office (SRO Bury 386.09.42644).
Described by Weston (S1) as "staunches Nos 4 & 5 (Lock No 10) TL 782714 LACKFORD DOUBLE LOCK. This consists of two staunches 283' apart, thus making and serving the function of a lock. A large meander [of the river] is by-passed by them."
Brick built lock and staunch abuttments separated by circa 283ft of river. The North gate has C18 yellow bricks near the waterline but mid C19 above. The South (upstream) gate only C19 brick, both gates show signs of C20 repair in Flettons. Examination was not thorough as it was done entirely from the East bank - these E structures could not be clearly seen (S3?).
It appears to be a 2-phase structure with the N lock having been used alone in the C18 and early C19. It has been compared to the Turf lock at Mildenhall (MNL 456) - this is not acceptable.
2010: A building recording project was carried out on two locations along the River Lark, Suffolk, to record two locks structures known as the Cavenham Lock and the Hengrave Lock, which had been part of the Lark Navigation. Some time was also spent monitoring repair works carried out on the Cavenham Lock. These observations revealed that both locks were of late 17th to early 18th century date and had been repaired at various points throughout their lifespan, up to and including the 20th century. They were mainly constructed from bricks of varying sizes, as well as a timber superstructure designed to reinforce the brickwork and to hold the locks gates, which were no longer present. Concrete, metal fittings and stone were also used (S4). Included in the Proceedings of the Suffolk Institute of Archaeology and History annual round up of individual finds and discoveries for 2010 (S5).