in 1966, lachute and the village of ayersville merged, forming the "cité de lachute". in 1971, during the construction of montréal-mirabel international airport, a part of the saint-jérusalem parish was added to lachute. in 1981, "cité de lachute" became "ville de lachute". in 2000, about 10 km of mirabel's territory were annexed by lachute. in 2002, the "service de police municipale de lachute" was transferred to the sûreté du québec.