Perimeter Highway (Winnipeg)

Provincial Trunk Highways (PTH) 100 and 101, collectively known as the Perimeter Highway, form a beltway around the Canadian city of Winnipeg, Manitoba. The Perimeter Highway is approximately 90 km in length and serves as a ring road around Winnipeg for through traffic. It is often considered by local residents to be the city's unofficial boundary, although approximately three-quarters of the Perimeter Highway actually lies in the other municipalities within the Winnipeg Metropolitan Region.

Route
The beltway consists of two provincial highways connected at separate junctions with PTH 1, the Trans-Canada Highway (TCH), on the east and west sides of the Winnipeg. The North Perimeter highway is officially designated PTH 101 and is part of Canada's National Highway System. The South Perimeter highway is designated PTH 100 and is the official TCH bypass around Winnipeg but not part of the National Highway System. The entire route is a four-lane divided expressway with a mixture of interchanges and at-grade intersections. After many highway authorities in Canada have moved away from the cloverleaf interchange in favour of other designs, Winnipeg has the most cloverleafs of any city in Canada, with all six being on the Perimeter Highway.

History, ongoing work, and future upgrades
The highway was originally built in 1955 to bypass city centre rush hour traffic. This was done in lieu of a more expensive freeway system within the Capital Region. The South Perimeter Highway bridge across the Red River and roadway at Pembina Highway/PTH 75 south was constructed in 1958. The job was tendered to Peter Leitch Construction Ltd. at a cost of $188,670. In December 1957, Dominion Bridge was awarded the contract ($80,157) to supply the structural steel for the overpass. When constructed, the Perimeter Highway was located entirely in surrounding municipalities well outside of Winnipeg's official city limits, however roughly one-quarter of the highway is now inside proper city limits following the municipal amalgamation of Winnipeg in 1972.

The Perimeter Highway was originally unconnected between PTH 59 and PTH 15 as PTH 59 had received significant upgrades, making the need for a northeast section less pressing. PTH 59 continued to serve as the de facto northeast leg of the Perimeter until the mid-1990s, when PTH 59 and PTH 15 were connected. The last remaining two-lane section was the PTH 59 north interchange, which was upgraded over a three-year span ending in 2018. The highway now encircles Winnipeg as a four-lane roadway.

Improvements were made to the western segment of the highway in the early 2010s when PTH 190, Centreport Canada Way, was constructed. In addition to the interchange that connected to this new highway, a flyover was constructed over Saskatchewan Avenue (PR 425) and the adjacent railway crossing; and the median was closed at the entrance to Assiniboia Downs leaving only right-in/right-out access from the southbound side.

In 2018, the province announced its intention to upgrade the South Perimeter Highway to a limited-access freeway, the starting point of which was to close a number of uncontrolled median openings and accesses. This was followed by the release of a full South Perimeter Highway Design Study that proposed a set of upgrades to transform PTH 100 into a six-lane, free-flowing, limited-access freeway. The full vision for the freeway design would be realized through two multi-year phases, with some of the upgrades potentially tying in with a new by-pass around St. Norbert. Initial upgrades include the ongoing construction and improvement of various service roads, and the construction of multiple interchanges to replace the various traffic lights on the highway.

The first major upgrade from this plan, the replacement of the traffic signals at St. Mary's Road with an interchange, is expected to be complete by 2024. Following its completion, the traffic signals at PTH 3 (McGillivray Blvd) in Oak Bluff will be replaced with an interchange, a project that is currently in the planning and detailed design phase. Recently, the government announced the start of the planning phase for the next major construction project, which will collectively replace the traffic signals at St. Anne's Road with an interchange, and replace the adjacent at-grade CPR crossing with an overpass.

In 2021, the government announced a comparable proposal to upgrade the North Perimeter Highway, PTH 101, to full freeway standards. The first portion of this upgrade included the closure of multiple uncontrolled medians and accesses. A larger functional design study has since been commissioned to determine the final recommendations for the North Perimeter Highway, which is expected to be complete by 2025.

Exits and crossings
Exit numbering begins at Fermor Avenue and increases clockwise.