Predecessors

The alignment of Highway 174 originated during the late 1940s. Aiming to bypass the winding and hilly route between Montreal and Ottawa, the Department of Highways, predecessor to the Ministry of Transportation, planned a new route for Highway 17. The majority of this new route was built along the right-of-way of a former Canadian Northern Railway track.^[13][14][15] Construction began in 1947 at Green's Creek, east of Gloucester, and proceeded east towards Rockland.^[13][16] Another contract, which began in August 1949, extended construction beyond Trim Road to Canaan Road.^[17] The new route, which was internally referred to as Highway 17 Alt, was completed and opened to traffic on November 10, 1952.^[15][18] However, it was not given unique designation until 1955.^[10][19][20]

To the west, construction of the Queensway was soon to begin. It was a major part of the Greber Plan, which was produced by Jacques Gréber under the direction of Prime Minister Mackenzie King in the late 1940s. Although Gréber had been corresponding with King as early as 1936, World War II halted any plans from reaching fruition at that time. Following the war, Gréber was again contacted and his expertise requested. He arrived on October 2, 1945 and began working almost immediately.^[21] The Greber Plan was released in 1950 and presented to the House of Commons on May 22, 1951.^[22] The plan called for the complete reorganization of Ottawa's road and rail network, and included amongst the numerous parkways was an east to west expressway along what was then a Canadian National Railway line.^[23][24]

With the rail lines removed, construction of the new expressway got underway in 1957 when Queen Elizabeth visited Ottawa to open the first session of the 23rd Parliament. On October 15, the Queen detonated dynamite charges from the Hurdman Bridge, which now overlooks the highway as it crosses the Rideau River, and formally dedicated the new project as the Queensway. At the ceremony, premier Leslie Frost indicated that the entire project would cost C$31 million and emphasized the importance of the link to the Trans-Canada Highway.^[25][26]

The Queensway was constructed in four phases, each opening independently. The section from Alta Vista Drive (now Riverside Drive) east to the split between Highway 17 (Montreal Road) and Highway 17 Alt was the first phase,^[27] and was opened to traffic on November 25, 1960, extending west to the Rideau River.^[28] Construction of a new freeway between Ottawa and Montreal, entirely bypassing the route of Highway 17, began in the late 1960s. Contracts to construct the route were opened to bidding on November 15, 1968; construction began in May 1969 starting at Base Line Road (now Ramsayville Road) and proceeding easterly.^[29][30] The segment of this new freeway that linked to the Queensway at The Split was the final one to open, on December 2, 1975.^[31] The portion of the Queensway west of the new interchange became part of Highway 417 by 1980, while the portion to the east remained part of Highway 17.^[32]

Extension of four-laning

The portion of Highway 17 immediately east of Montreal Road quickly became known for routine fatal accidents. During the course of a 27-month study conducted between 1966 and 1969, 56 deaths occurred on what had by then become known as the "killer strip".^[33] However, the provincial government was reluctant to upgrade the highway due to the construction of Highway 417 between Ottawa and the Quebec boundary, which it expected would handle the majority of traffic.^[34] However, despite the completion of Highway 417 at the end of 1975, crashes continued to occur on the 3-kilometre (1.9 mi) stretch Highway 17 west of Champlain Street, including 132 in 1978, 5 of which were fatal. Residents and local politicians began a campaign by early 1979, pressuring the provincial government to widen the route and build interchanges.^[35]

The province announced the widening of Highway 17 from Montreal Road to Champlain Street on April 15, 1980;^[36][37] construction began in late May and was scheduled for completion in November, but would not include any grade-separations or interchanges.^[38] The Jeanne D'Arc Boulevard interchange was built in 1985.^[39] Studies began in 1986 to examine the Highway 17 corridor east of Ottawa, and recommended that the route be widened between Champlain Street and Trim Road.^[40] Reconstruction of the section between Champlain Street and Trim Road was officially announced on May 17, 1988.^[41] Work began in mid-1990, with the highway being detoured onto the future offramps to Champlain Street to allow the at-grade intersection to be rebuilt.^[42] the Champlain Street/Place d'Orleans interchange and the Tenth Line Road interchange were opened along with the widened Highway 17 on November 4, 1994.^[43]

Despite the protests of the city that the road served a provincial purpose, a second round of transfers saw Highway 17 east of Ottawa downloaded entirely on January 1, 1998 adding 12.8 km (8.0 mi) to the length of Regional Road 174. The Trans-Canada Highway designation was subsequently moved from the former Highway 17 to Highway 417. Ottawa immediately renumbered the transferred sections of Highway 17 as Regional Road 174.^[44] Regional Road 174 was renamed Ottawa Road 174 when the Regional Municipality of Ottawa–Carleton amalgamated with the municipalities of the region to form the new City of Ottawa in 2001.^[45] The region, and later city, as well as the neighbouring county of Prescott-Russell, have petitioned the provincial government to "upload" the route back into the provincial highway network since then, and as recently as December 2021.^[46][47]

Despite no further work occurring since 1994 to extend the widening beyond Trim Road, several Environmental Assessments (EAs) have taken place since 1988, particularly to widen the segment between Trim Road and Prescott-Russell County Road 8 (Landry Road) near Rockland to a limited-access highway with a central concrete barrier.^[48][49]

Uploading to Provincial Government

On March 28, 2024, Ontario Premier Doug Ford announced^[3] a phased plan to guide the upload of Ottawa Road 174 to the province. The announcement was made alongside Ottawa Mayor Mark Sutcliffe. The deal between the provincial and municipal government was made as a part of a larger agreement for city funding. The funding included maintenance and rehabilitation for Ottawa Road 174 while a three-stage phased assessment of potential provincial ownership of the road is underway.