Route planning documents show two proposals that may utilize the Highway 58A corridor: a southern extension of Highway 406 and the eastern portion of the Mid-Peninsula Highway, referred to as the Niagara South Highway in planning documents.
Documents outlining route plans suggest using Highway 58A for two different purposes: extending Highway 406 southward or building the eastern section of the Mid-Peninsula Highway, which is called the Niagara South Highway in planning materials.