Hillsborough River Bridge

The Hillsborough River Bridge refers to two separate Canadian bridges which crossed the Hillsborough River estuary between Charlottetown and Southport (now know as Stratford) in Queens County, Prince Edward Island.

Railway bridge, 1905-1962

The first crossing of the Hillsborough River, a 30 km long and up to 1 km wide tidal inlet which emptied into Charlottetown Harbour, was a used railway bridge.

The bridge opened in 1905 after the Prince Edward Island Railway, a railway company owned by the Government of Canada, constructed a railway line from Charlottetown to Murray Harbour. At the time of its construction, the railway line was built using the narrow gauge of 3 ft 6 in (Cape gauge). The last remaining link in this line involved crossing the Hillsborough River from Charlottetown to Southport.

The Government of Canada owned the Intercolonial Railway, a sister company to the PEIR in the neighbouring Maritime provinces and Quebec, and was upgrading its mainline through northeastern New Brunswick to handle heavier locomotives and rail cars. The Intercolonial Railway crossed the Southwest Miramichi River and Northwest Miramichi River between Nelson and Newcastle using two iron bridges set upon stone piers, as designed by engineer-in-chief Sir Sandford Fleming.

These spans were considered surplus after their heavier replacements were installed, thus the federal government decided to salvage the structure for use on the PEIR's line to Murray Harbour. Both bridges, consisting of 12 spans, were transported on barges to Prince Edward Island.

Before installing the used bridge from New Brunswick, the PEIR hauled thousands of rail car loads of soil excavated alongside the railway line east of the St. Dunstan's University campus several miles northwest of the bridge abutment. These railcars were pushed in 10-15 car trains to the waterfront and used to in-fill large areas for expanded rail yards and wharves, as well as to build an approach causeway from the Charlottetown side. A corresponding approach causeway was built on the Southport side using soil excavated along the railway line in Bunbury east of the bridge.

The remaining gap had 11 stone piers constructed deep into the mud of the Hillsborough River using cofferdams and high pressure air, with stone being imported from Nova Scotia and cemented into place atop the sandstone bedrock beneath the riverbed. The bridge had a motorized swing span in the centre to permit ship traffic to operate upriver on the Hillsborough River with 2 supporting piers when the span was opened.

The bridge opened in 1905 and immediately revolutionized travel in southeastern Prince Edward Island, allowing narrow gauge passenger and freight trains to operate between Charlottetown and Murray Harbour, as well as pedestrians and horse-drawn carriages and sleighs (and later automobiles) to use the bridge when trains were not crossing; for this purpose, wood planks were placed between and on each side of the rails.

The railway bridge saw steady use through to the early 1930s when the PEIR's successor, Canadian National Railways (CNR), completed the conversion of its rail lines in the province from narrow (3 ft 6 in) to standard (4 ft 8.5 in) gauge. The larger dimensions and weight of standard gauge rail cars and locomotives saw the railway's structural engineers deem the railway bridge unsafe, so a bypass route from Mount Stewart Junction to Lake Verde Junction was built as a depression-era project.

Following the opening of the "Short Line", all heavy rail traffic bound for Murray Harbour was routed through Mount Stewart. The rails on the Hillsborough River Bridge were standard gauged but only lightweight rail cars and locomotives were permitted to use it, thus its use by CNR declined markedly.

In 1950 CNR structural engineers felt the bridge was unsafe for any rail traffic and the rails were removed while the railway instituted taxi service for passengers travelling to Murray Harbour, allowing them to board passenger trains at its terminus near the bridge abutment in Southport.

No longer used for rail traffic, CNR wished to rid itself of operating the bridge and tried to get the provincial government to take ownership of the structure. The provincial government, which had been getting away with having the federally-owned railway company operate this important bridge for many years, sought to delay any handover and at one point in the early 1950s, CNR engineers barricaded the bridge to public travel, partly out of concern that the bridge was unsafe, and partly to pressure the provincial negotiators.

The provincial government was outraged and Premier J. Walter Jones staged a publicity stunt at the Charlottetown abutment of the bridge, boarding a bulldozer and demanding in front of local media, that the bridge be reopened.

CNR relented and reopened the bridge, making temporary repairs, however the long-term viability of the bridge, then approaching 85 years of age, was in doubt.

Highway bridge, 1962-present

By the late 1950s, the federal government began to develop the Trans-Canada Highway network across the country and sought to fund a route between the ferry terminals in Borden and Wood Islands via Charlottetown.

The federal and provincial governments jointly funded the construction of a new 2-lane highway bridge to carry Route 1 over the Hillsborough River parallel to, and immediately upstream of, the 1-lane railway bridge.

This new bridge used the original soil-infilled approach causeways on both sides of the river that were constructed for the railway bridge, however these were widened to the Trans-Canada Highway standard width of 3 lanes (2 travel lanes and emergency shoulders), as well as lengthened to narrow the spanned distance to roughly half that of the railway bridge.

The new bridge structure was constructed using structural steel as an arched truss using 2 piers. The emergency shoulders on the bridge structure were occupied by concrete sidewalks.

The original railway bridge was dismantled and the iron structure was scrapped, although the stone piers were left in place. These proved to be a popular nesting site for a colony of cormorants throughout the 1960s-1990s. Ice and wind and wave damage by the turn of the 21st century had caused the majority of the original railway bridge piers to collapse and are mostly invisible from the highway bridge.

In 1992 the Government of Canada signed an agreement with Strait Crossing Joint Venture, an international construction consortium, to build the Northumberland Strait Crossing Project (today known as the Confederation Bridge) between Prince Edward Island and New Brunswick. Part of the agreement negotiated with the Government of Prince Edward Island provided for a federal-provincial cost-sharing to have Strait Crossing Joint Venture expand the Hillsborough River Bridge from 2 lanes to 4 lanes.

This expansion had been studied since the late 1970s when traffic delays began to occur as residential development took place in areas east of Charlottetown, namely the communities of Bunbury, Southport, Kinlock, Keppoch and Cross Roads, creating changes in commuting patterns. Studies indicated that vehicle counts on the 2-lane bridge were approaching 30,000 trips per day.

SCJV expanded the 1962-era Hillsborough River Bridge in 1995, placing additional continuous span girders on each side of the original structure with expanded piers, then removal of the guardrails and concrete sidewalk and bridge deck from the original structure, replacing it with an integrated deck. This work took place without any significant delays or closures.

Additional work was undertaken by the provincial government on the approach routes to the span, with additional infilling of Charlottetown Harbour to extend Water Street through the former railway yard (CN Rail abandoned rail service in PEI on December 31, 1989) and intersection with Grafton Street and Riverside Drive. Additional redesign work was undertaken on the Southport side of the bridge to allow for a more efficient traffic flow.

References

* [http://www.city.charlottetown.pe.ca/search/story_hillsboro_br.cfm Hillsborough Bridge]
* [http://www.mountstewartpei.com/birding.html Hillsborough Bridge tern and cormorant colonies]
* [http://www.town.stratford.pe.ca/about/about_history.cfm Town of Stratford history]
* [http://www.chrs.ca/Rivers/Hillsborough/Hillsborough-F_e.htm Canadian Heritage River System - Hillsborough River]
* [http://www.archives.pe.ca/finding_aids/4559.pdf Construction of certain Bridges, Causeways, and Water Control Structures in P.E.I. Period 1951 to 1994 - O.J. McCulloch Engineering Consultants Inc., Public Archives and Records Office, Province of Prince Edward Island]