King's Highway 40, commonly referred to as Highway 40, is a provincially maintained highway in the southwestern portion of the Canadian province of Ontario. The route links Chatham and Sarnia via Wallaceburg, following close to the St. Clair River. The southern terminus is at Highway 401 south of Chatham, while the northern terminus is at Highway 402 in Sarnia.

Highway 40 was built as a depression-relief project in 1934. The original routing followed what is now the St. Clair Parkway, but was rerouted to create that scenic road in the mid-1970s. The Sarnia Bypass was built between 1963 as Highway 40A and renumbered as Highway 40 by 1965; the original route through Sarnia became Highway 40B until it was decommissioned during the early-1990s. The route was extended to Highway 3 in Blenheim during the early 1970s; however this section would be the sole part of Highway 40 decommissioned during the Ontario highway transfers. The route is 91.8 km (57.0 mi) long.

Route description

Highway 40 begins at an interchange with Highway 401 (Exit 90) southeast of the urban centre of Chatham, within the Municipality of Chatham-Kent.[3] Southwest of the interchange is C.M. Wilson Conservation Area, a 30 hectares (74 acres) campground named for the former Chair of Directors of the Lower Thames Valley Conservation Authority, Clarence Michael Wilson.[4] The highway proceeds northwest as Communication Road, passing between farmland on the outskirts of Chatham. It crosses a Canadian National Railway (CN) mainline followed by the Thames River, then turns southwest onto Grand Avenue East and crosses a Canadian Pacific (CP) railway line. The highway progresses from the outskirts of Chatham to downtown before turning onto St. Clair Street and travelling northwest. It encounters the Nortown Centre mall as it passes through the suburbs and eventually leaves the city.[3]

Between Chatham and Wallaceburg, Highway 40 divides a large swath of farmland established in the fertile soils of the region. The only community between the two places is Oungah, Ontario. Immediately southeast of Wallaceburg, the highway turns to the north and becomes known as Murray Street. As it enters the town, it turns onto McNaughton Avenue and crosses a CSX railway line then the Sydenham River. The route turns west onto Dufferin Avenue and proceeds out of the town, crossing the CSX railway a second time. After crossing an irrigation canal, Highway 40 turns north onto Arnold Road and crosses the CSX railway a third and final time before exiting Chatham–Kent.[3]

The route enters Lambton County in the municipality of St. Clair, passing through more farmland.[3] Seven kilometres (4.3 mi) north of the county line, the highway crosses the W. Darcy McKeough Floodway, a channel constructed in 1984 to protect Wallaceburg from flooding.[5] Highway 40 continues north parallel to and several kilometres east of the St. Clair River. At Bickford, it swerves slightly to the east while passing between the CF Industries nitrogen fertilizer plant to the west and Bickford Oak Woods Provincial Conservation Reserve to the east.[3][6] As the highway approaches the south end of Sarnia, it widens into a divided four lane expressway and passes through Chemical Valley, the location of several industrial plants.[7] The route enters Aamjiwnaang First Nation at La Salle Line wherr the surroundings abruptly switch to forest from a mix of industry and farmland.

At the intersection with Churchill Line, Highway 40 enters the Sarnia city limits and turns east onto the Sarnia Bypass. Approximately three kilometres (1.9 mi) east of the intersection, the highway narrows back to a two lane road. Soon thereafter, it gently curves to the north, intersecting Plank Road and becoming Modeland Road. It passes along the western edge of the Sarnia Photovoltaic Power Plant, the world's largest photovoltaic (solar) power plant.[8] The route passes above a CN and VIA rail line as it travels along the eastern rural–urban fringe of the city. After a signalized intersection with Wellington Street, Highway 40 widens to a divided four lane road once more just prior to an interchange with London Line (former Highway 7), then ends at an interchange with Highway 402 (Exit 6). Modeland Road continues north as Lambton County Road 27.[3]

The African-Canadian Heritage Tour follows a portion of Highway 40, from the interchange with Higwhay 401 to Chatham-Kent Road 29 (Countryview Line) in Oungah, Ontario, midway between Chatham and Wallaceburg, where it turns east on to Road 29 towards Dresden.


Highway 40 was established at the height of the Great Depression, during the spring of 1934. The subsequent improvement of the roadway employed several dozen men eight hours per day, six days per week at minimum wage as a depression-relief project.[9] Highway 40 was created by the assumption of several lengths of concession road created as a result of statute labour by adjacent farmers as part of the requirements to secure a land deed. On March 28, the road connecting Chatham with Wallaceburg was assumed by the Department of Highways (DHO) and designated King's Highway 40. Just over a month later, on May 2, the DHO assumed the route between Wallaceburg and Sarnia known today as the St. Clair Parkway. The 50.1-mile (80.6 km) route connected Highway 2 in Chatham with Highway 7 and Highway 22 in Sarnia.[1]

Sarnia Bypass

In the decade following World War II, automobile use in North America increased dramatically, inundating many highways on the approach to and within urbanized areas with heavy traffic. As a result, freeways and bypasses were constructed throughout the province, allowing drivers not destined for those locations avoid congestion. In 1957, the DHO announced that Highway 402 would be extended east of Sarnia to London, starting with the construction of an interchange at Modeland Road.[10] This interchange would serve as the terminus for a new bypass of Sarnia.[11] On May 1, 1963, portions of Modeland Road and Churchill Line were taken over by the DHO and numbered as Highway 40A. These roads were reconstructed over the following year as a continuous divided highway. On October 25, 1963, the Sarnia Bypass was opened to traffic.[12] By 1965, the bypass was renumbered as the northern end of Highway 40; the former route on the west side of Sarnia, via Brock Street, Vidal Street and Front Street, was subsequently renumbered Highway 40B.[13]

During the early 1970s, the province extended Highway 40 along Kent County Road 11, to meet with Highway 3 in Blenheim, Ontario, adding 17 km to the roadway's distance.

East of the Murphy Road overpass, Highway 402 was re-aligned to bypass the original interchange with Highway 40 constructed in 1963; Exmouth Street was redirected to connect with Highway 7 (London Line) at that junction, and Quinn Street now follows the former alignment of the freeway.[14] For the realigned Highway 402, a new interchange was constructed with Highway 40 just north of the original interchange.[15]

St. Clair Parkway

During the late-1950s, the Saint Lawrence Seaway project created a navigable lock system between the Atlantic Ocean and Lake Superior, while simultaneously reclaiming properties along the shoreline to create a continuous parkway. Seeing the potential tourist draw, several groups and organizations, including the district Chamber of Commerce, convened at the second annual conference of the Southwestern Ontario Chambers of Commerce and Boards of Trade in February 1960. Several resolutions were passed, calling for the DHO to create a new Highway 40 several kilometres inland from the St. Clair River and to have the old highway rebuilt as a scenic route.[16] These resolutions were echoed by Lambton County Council and the 21 municipalities in the county.[17]

Plans for the parkway were crafted over the next several years before being presented to minister of highways Charles MacNaughton in the spring of 1965.[18] Subsequently, the St. Clair Parkway Commission was formed in 1966.[19] Construction of the new inland route of Highway 40 began in 1972. Working south from Sarnia, the first contract reached as far south as Highway 80, a distance of 13.4 km (8.3 mi).[20] A second contract, awarded in 1974, extended construction south an additional 11.0 km (6.8 mi) to Lambton County Road 2.[21]

Construction began in the early 1970s on a major realignment of Highway 40 between Wallaceburg and Sarnia. The old alignment of the road was bypassed by a newly constructed (and much straighter) road around 5 km inland from the St. Clair River. This new alignment of Highway 40 opened in stages in the mid-1970s. From roughly halfway between Highway 80 (now Lambton CR 80) and CR 4, to the Sarnia Bypass, the road was built as a four-lane divided highway. Once this new alignment was created, the road's length was 103.1 kilometres (64.1 mi), as around 44 kilometres (27 mi) of the old alignment was bypassed.

The old alignment was turned back from Sarnia to Sombra in 1979, from Sombra to Walpole Island in 1980, and finally from Walpole Island to Wallaceburg in 1984. It was named the St. Clair Parkway and designated as Lambton County Road 33 and Kent County Road 33.

The new (current) alignment of Highway 40 was built with a wide-enough right of way for future twinning and upgrading to become a freeway, if the need ever arises. There are no private properties on Highway 40's new alignment, and the only access is at intersecting roads, or at traffic signal-governed intersections, which may become overpasses and interchanges if upgrading takes place. The entire Sarnia Bypass (along the south and east ends of Sarnia) is also built to this standard for relatively easy upgrading. At the moment, the only parts of the Bypass which are four-lane divided are the Michigan Avenue to Wellington Street stretch and from Indian Road to Churchill Road, the latter where Highway 40 changes direction from east-west to north-south to lead to Wallaceburg. The Highway 40 remains a four-lane divided road from the change of direction to north-south to just south of Rokeby Line.


April 1, 1997 saw a huge change in Ontario's provincial highway network: over 4000 km of highways were turned back to county, city, and local authorities. Highway 40 was largely spared, although south of Highway 401, the road was turned back, shortening the road by the 17 km it gained in the 1970s.

January 1, 1998 saw further changes to Highway 40. It was rerouted through Chatham, Ontario along the route of Former Highway 2 (along Grand Avenue), instead of its old route through downtown via Third Street, Wellington Street, Lacroix Street, and Park Avenue. Highway 40 is now 91.8 kilometres (57.0 mi) long.

Major intersections

The following table lists the major junctions along Highway 40, as noted by the Ministry of Transportation of Ontario.[2] 

Division Location km[2] mi Destinations Notes
Chatham–Kent Blenheim −9.9 −6.2  Highway 3 (Talbot Street) Decommissioned, former southern terminus prior to 1998
Kent Centre 0.0 0.0  Highway 401 Exit 90
  0.3 0.19 County Road 14 east (Pinehurst Line)
1.5 0.93 County Road 14 west (Creek Road)
5.3 3.3 County Road 18 east (Fairview Line)
Chatham 6.2 3.9 County Road 30 north (Communication Road)
County Road 2 east (Longwoods Road) – London, Thamesville
Former Highway 2 junction, beginning of concurrency
12.3 7.6 County Road 2 west (Grand Avenue) – Windsor, Tilbury Former Highway 2 junction, end of concurrency
  19.1 11.9 County Road 35 (St. Andrews Line / Eberts Line)
Oungah 23.4 14.5 County Road 29 (Countryview Line) – Dresden
  30.5 19.0 County Road 42 (Electric Line / Oldfield Line)
Wallaceburg 39.6 24.6 County Road 78 east – Dresden Formerly Highway 78
42.2 26.2 County Road 33 (Dufferin Avenue) To St. Clair Parkway
Lambton St. Clair 49.0 30.4 County Road 1 west (Lambton Line) – Port Lambton
55.8 34.7 County Road 2 (Bentpath Line)
66.6 41.4 County Road 80 (Courtright Line) – Courtright, Brigden Formerly Highway 80
74.6 46.4 County Road 4 (Petrolia Line) – Corunna, Petrolia
Sarnia 77.3 48.0 County Road 35 (La Salle Street) City limits
80.1 49.8 Churchill Line Old Highway 40; route turns east onto Churchill Line
82.8 51.4 County Road 29 north (Indian Road)
85.2 52.9 County Road 20 (Plank Road) Churchill Line becomes Modeland Road
87.9 54.6 County Road 25 (Confederation Street)
90.7 56.4 County Road 22 (London Line) – London Formerly Highway 7
91.4 56.8  Highway 402 – London, Sarnia To Blue Water Bridge to United States
92.0 57.2   Former ending of Highway 40 prior to 1998
1.000 mi = 1.609 km; 1.000 km = 0.621 mi
  •       Closed/former


  1. ^ a b "Appendix 4 - Schedule of Assumptions and Reversions". Annual Report (Report). Department of Highways. March 31, 1935. pp. 119–120. 
  2. ^ a b Ministry of Transportation of Ontario (2010). "Annual Average Daily Traffic (AADT) counts". Government of Ontario. Retrieved January 15, 2014. 
  3. ^ a b c d e f Ontario Back Road Atlas (Map). Cartography by MapArt. Peter Heiler. 2010. p. 6, 12. § B7–T10. ISBN 978-1-55198-226-7. 
  4. ^ "C.M. Wilson Conservation Area". Lower Thames Valley Conservation Authority. Retrieved January 15, 2014. 
  5. ^ Phair, John (June 21, 2011). "McKeough Floodway controversial but has done its job, SCRCA says". Today's Farmer. Canoe Sun Media. Retrieved January 15, 2014. 
  6. ^ "Plants: Courtright, Ontario". CF Industries Holdings. Retrieved January 15, 2014. 
  7. ^ Morden, Paul (July 10, 2013). "New frack tower part of $250-million upgrading for Corunna plant". The Sarnia ObservEr. Canoe Sun Media. Retrieved January 15, 2014. 
  8. ^ CBC News (October 4, 2010). "Enbridge completes Sarnia solar farm". Canadian Broadcasting Corporation. Retrieved October 5, 2010. 
  9. ^ Annual Report (Report). Department of Highways. March 31, 1935. p. 96. 
  10. ^ "Sarnia Link to 401 Project". Windsor Daily Star. September 12, 1957. p. 20. 
  11. ^ "Highway District Reports - District 1 - Chatham". Annual Report (Report). Department of Highways. March 31, 1963. p. 77. 
  12. ^ A.A.D.T. Traffic Volumes 1955–1969 And Traffic Collision Data 1967–1969. Ontario Department of Highways. 1970. pp. 80–81. 
  13. ^ Ontario Road Map (Map). Cartography by C.P. Robins. Ontario Department of Highways. 1965. 
  14. ^ Google (June 24, 2010). "Quinn Drive - Former Highway 402 alignment" (Map). Google Maps. Google. Retrieved June 24, 2010. 
  15. ^ Highway Construction Program: King's and Secondary Highways. Ministry of Transportation and Communications. 1972–1973. p. xi. 
  16. ^ "Chambers Support Parkway". The Windsor Star. March 1, 1960. p. 3. Retrieved August 21, 2012. 
  17. ^ Bennie, Jim (December 8, 1960). "Area Chambers Support Back New Highway, Parkway". The Windsor Star. p. 1. Retrieved August 21, 2012. 
  18. ^ Stewart, Bill (March 12, 1965). "MacNaughton to See St. Clair Parkway Plans". The Windsor Star. p. 3. Retrieved August 21, 2012. 
  19. ^ Morden, Paul (January 19, 2009). "Parkway History Needs a Home". The Observer. Sarnia: Canoe Sun Media. Retrieved June 12, 2015. 
  20. ^ Highway Construction Program. Ministry of Transportation and Communications. 1972–73. p. ix. 
  21. ^ Highway Construction Program. Ministry of Transportation and Communications. 1975–76. p. x. 

External links

Route map: Google

KML is from Wikidata