AWE - Penstocks

Penstocks are also known and referred to as sluice gates, slide gates or water gates. The word ‘penstock’ originates from the days of water mills where a pond (a body of stored or ‘penned up’ water) was used to feed the water wheel or mill race and was referred to as the ‘pen’. The timber stoplogs used to control the flow onto the water wheel was called the ‘stock’. Later, as the need to accurately control the speed of the water wheel became more critical, a single sliding gate operated with a lifting mechanism replaced the stoplogs. During the 17th century, the words ‘pen’ and ‘stock’ became combined into a single word – PENSTOCK.