Canal Safety Gates

Canal Safety Gates or Canal Air Raid Protection Gates are structures that were installed on canals specifically to reduce or prevent flood damage to dwellings, factories, etc. in the event of aqueducts, canal banks, etc. being breached either through natural events or by enemy action during wars, insurgency, sabotage, etc. They sometimes have a secondary function in regard of canal maintenance work. Substantial structures or simple 'Stop Gates' or 'Stop Planks' were used to prevent flooding and were usually only put in place when air raid warnings were given.

Large volumes of stored water have considerable destructive potential and where structures such as canals run on embankments above low lying built up areas or where aqueducts exist, appropriate safety precautions were taken either as a war time contingency or at the time of construction. These 'Canal Safety Gates' or 'Canal Air Raid Protection Gates (ARPG)' were constructed and installed in regard to the scale of the danger posed and ranged from simple wooden planks known as 'Stop Gates' or 'Stop Planks' to more massive constructions built of concrete and steel such as the safety gates built on the Forth and Clyde Canal near and on the Glasgow Branch at Firhill Road and Craighall Road.

Where a water link was no longer commercially important, but still represented a risk in case of damage, it might be closed off permanently with concrete or an earth bank. This was done in Bristol at the beginning of WWII to protect the floating harbour by blocking the river access from the harbour at Bathurst Basin and the Feeder Canal at Totterdown Basin.

In 1942 two massive steel safety or stop gates were constructed on the Edinburgh side of at what is known as the Stockingfield Narrows. The purpose of these two hand cranked steel gates was to hold back the waters of the Forth and Clyde Canal to prevent serious flooding in Glasgow in the event of bombing destroying or breaching the nearby Stockingfield Aqueduct. The nearest lock on the Edinburgh main line that could control the water loss after a breach is 17 miles away at Wyndford, Lock 20.

Further sets of safety or stop locks were also created in WWII on the Glasgow Branch at the Firhill Road Narrows and at Craighall Road Narrows near Speirs Wharf, protecting the city from potential damage to the two aqueducts on this route. The Stockingfield Narrows gates are substantially intact whilst mainly the concrete parts of the structures remain at Firhill Road Narrows.

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Wikipedia