Piara Waters is a southeastern suburb of Perth, Western Australia within the City of Armadale. Previously part of Forrestdale and gazetted in 2007, Piara Waters is located approximately 20 kilometres south-southeast of Perth. A large, central part of the suburb is taken up by the Piara Nature Reserve. This area was set on fire in March 2012 and threatened homes, but the fire was successfully contained by firefighters. As a suburb that has been converted from small farms to residential lots, the population of Piara Waters has grown significantly from fewer than 100 in 2006 to over 14,000 as of 2021. To accommodate this growth, new community and sporting facilities have spawned. Piara Waters Primary School was opened in February 2012 and caters for students from Kindergarten to Year 6.