The City of Mountlake Terrace has two main surface water drainage courses, one on the west and one on the east side of the city. Hall Creek, Lake Ballinger and McAleer Creek comprise the main drainage features on the west side of the city. Lyon Creek is the main drainage course on the east side of the city. There are several branches of the creek within the city converge into one channel at the Cedar Way Detention facility located in the 23900 block of Cedar Way. Downstream of the detention facility, Lyon Creek enters into the City of Lake Forest Park at the intersection of Cedar Way and 244th Street Southwest / 205th Street Southwest at the Snohomish/King County border and eventually drains into Lake Washington east of the Lake Forest Park Town Center.