Allan’s Dam & Allan’s Dam Bridge, Guelph, Speed River.
Our own research revealed that Allan’s Dam is a legacy mill dam, originally constructed in the 1830s to power Allan’s Mill—one of Guelph’s founding industrial sites. Sometime later, the structure was adapted for hydroelectric generation, likely in the early to mid-20th century. It is our understanding that this facility has not generated electricity for several decades and now functions only as an aging dam, concrete spillway and sluiceway, impounding a shallow headpond on the Speed River. It appears that this infrastructure no longer serves any useful purpose while continuing to fragment habitat, degrade water quality, and emit copious amounts of carbon, methane, and nitrous oxide into the atmosphere.