Townhead Reservoir, now called Banton Loch and known locally as the Big Dam supplies water to the summit level of John Smeaton’s Forth and Clyde Canal 1km to the south of the Colzium Lennox Estate.
The site of Banton Loch is between the village of Banton and Kilsyth and the loch is not a natural formation but is man-made. Prior to a reservoir being formed at this location the site was the scene of The Battle of Kilsyth on 15th August 1645. James Graham, 5th Earl of Montrose (Royalists) and General William Baillie of Letham (Covenanters) met on the battle field now under water. Montrose’s army defeated the Covenanters and a slaughter of the remaining Covenanters took place with General William Baillie escaping over Dullatur Bog a deep and treacherous marshy area lying to the south of Banton Loch and eventually reached his cousin’s house in Castle Cary (now Castlecary) and eventually to Stirling Castle.
The slopes along the north side of Banton Loch are known as ‘Slaughter Howe’ and the area to the north west of the loch is known as ‘Baggage Knowe’ there are other areas called ’Drum Burn and Bullet Knowes’
A land-surveyor John Laurie surveyed the site of Banton Loch for Civil Engineer John Smeaton in early 1770 and work on the dam and reservoir started in May 1770. By August 1772 the dam was finished and in the summer of 1773 the reservoir was full of water ready for use in the Forth and Clyde Canal.
The site topography is such that an earth-fill dam some 7.6 metres at its highest point, with a crest a little less than 90 metres long, was enough to impound a reservoir covering 21.9 hectares. It contains almost three quarters of a million cubic metres of water, enough to fill 2,245 canal locks the size used at the eastern end of the Forth and Clyde Canal.
The reservoir is the main source of water for the 25.7kilometre summit-level stretch of the canal which is 47.2 metres above the low water level of the River Forth.
In more recent times during the late 1800’s the reservoir was used by the curlers of the Kilsyth Curling Club. At the east end of the reservoir the two curling clubs located in the village of Banton at that time used the reservoir and at one time there was also a yachting Club using the reservoir. Today Banton Loch (The Reservoir or Big Dam) is used for fishing and its shores used for walking or watching the varied wildlife that frequents the water and surrounds.