Houghton Highway

Houghton Highway
Houghton Highway at sunset
Coordinates	27°16′43″S 153°04′05″E
Carries	Motor vehicles, 3 lanes
Crosses	Bramble Bay
Locale	Redcliffe (Clontarf) north end, Brisbane (Brighton) south end, Queensland, Australia
Official name	Houghton Highway
Maintained by	Department of Main Roads
Characteristics
Design	Reinforced concrete viaduct
Total length	2,740 metres (8990 ft)
Width	11.1 m (36.1 ft)
History
Opened	20 December 1979
Location

The Houghton Highway is a 2.74 km (8990 ft) reinforced concrete viaduct, shortening the road distance between the cities of Redcliffe and Brisbane in Queensland, Australia. It is the longest bridge in the country, the third largest in the Southern Hemisphere.

Almost immediately after opening it faced a greater capacity task than originally intended, and in later years became a contentious issue politically with concerns about its ability to meet growing traffic demands, refusal to build another bridge, and the lowering of its speed limit.

History

With rising traffic levels on the two-lane Hornibrook Bridge in the 1970s, the Department of Main Roads investigated the construction of another structure to increase capacity and cope with future demand. Authorisation by the department was given to construct a new bridge in 1977, and the new Houghton Highway opened on 20 December, 1979, by the then Premier of Queensland, The Hon Sir Joh Bjelke-Petersen.

The Houghton Highway is named after The Hon James 'Jim' Houghton, Member for Redcliffe (1960-1979) and Speaker (1974-1979). Houghton resigned from parliament on 7 August, before the bridge opened.

Design

Roosting pelicans are an icon of the bridge ...Except on five light poles with deterrents. While the 2006 trial of the Daddi Long Legs-brand bird deterrents was successful, considerable misinformation that pelicans would be injured has put-off their rollout to the other 44 light poles.

The all-concrete Houghton Highway consists of 99 spans atop of some 400 T-beams, supported close to sea level by headstocks connected to five octagonal piles each.

Rough ride

A notable characteristic of the Houghton Highway, other than its significant length, is the particularly rough surface and therefore ride quality. In addition, each concrete span has a slight concave curve, so a distinct corrugated ride is felt when driving over the bridge. These unfinished surface characteristics are due to the absence of a bitumen overlay.

Worst road recognition

In February 2004, an RACQ survey recognised the Houghton Highway as the number one "pain in the neck" with Queensland motorists. Some 1200 members responded to this survey, asking them to nominate problem roads and intersections in the state. Respondents identified problems with insufficient capacity, problems with tidal flow or an accident/breakdown on the bridge causing major congestion, an inappropriate speed limit (60 km/h trial, now permanent), and the lack of consideration given by authorities to another bridge crossing.

Original layout and intention

The original intention of the Houghton Highway was to eventually carry two lanes of southbound traffic, with the old Hornibrook Bridge rejuvenated for two lanes of northbound traffic, doubling original capacity. When the Houghton Highway opened, it simply temporarily replaced the old bridge with the same capacity of one lane in each direction while the refurbishment was conducted.

The initial deck layout (from west to east) consisted of two 3700 mm lanes, an 1800 mm shoulder or "breakdown lane", and a 1900 mm footway. With just a diminutive reinforced concrete kerb to separate pedestrians from 80 km/h passing traffic, the use of the footway was minimal. While the bridge had a southbound breakdown lane, it did not prevent severe disruption to northbound traffic caused by breakdowns in that direction. This layout may appear to be a design oversight; however, it is important to remember that the two-way traffic flow was only meant to be temporary.

With the Hornibrook Bridge now closed for refurbishment, engineers were able to make a closer examination to determine more clearly the extent of work required. They found that deterioration of the bridge was worse than first expected, and the cost to bring the old bridge up to an acceptable standard, and its continued maintenance, would be far greater than original predictions. At the same time, the state government believed that Redcliffe's future growth would be in its western areas, and therefore the connections of Redcliffe to the Bruce Highway should receive more attention – the original land-based and much longer route to Brisbane before the Hornibrook Bridge opened in 1935.

Increasing capacity with just one bridge

A rejuvenated Hornibrook Bridge now not an option, in October 1982 the Department of Main Roads ordered an investigation into modifying the Houghton Highway, only ten months after it opened. Facing an awkward situation where the new bridge would not deliver any increased capacity but just keep the status quo, the modification of the bridge was to be urgently completed within twelve months.

The investigation found that, with the removal of the unsafe and unpopular pedestrian footway, the bridge could accommodate three lanes, and a tidal flow arrangement would provide extra capacity of two lanes where and when it was needed most – southbound in the morning and northbound in the afternoon and evening (reverse on weekends). Because this new layout did not involve breakdown lanes, emergency telephones and overhead lighting were also fitted to the bridge at the same time. Interestingly, the Houghton Highway did not originally include overhead lighting, whereas the old bridge did.

Modifications to the bridge commenced in March 1982, and completed by 3 September the same year, at a total cost of $435,000. Materials used included six gantries, eight switchable message signs, 54 traffic signals, two mast arms, 51 overhead lights, 12 emergency telephones, 27.5 km of power cable and 2 km of communication cable.

Cracking and deterioration

A routine inspection of Houghton Highway in 1991 found an alkali-silica reaction in the prestressed concrete piles. This reaction caused internal cracking of the concrete, and crumbling and spalling of the concrete leaving the reinforcing steel exposed to the marine environment.

Some 500 piles were encased in concrete below the water surface and up to 500 mm above the high water level. Above this point, an externally bonded carbon fibre reinforced polymer was applied, wrapping the column to cover the damage and contain and conceal the existing cracks. It was also believed that such composites offered re-strengthening and a protection of the piles through encapsulated resin during the lamination.

The treatment work was completed in 2000, and the repairs and condition of the piles are continually monitored.

Upgrading and political controversy

Concerns about increasing traffic demands and questions about the capacity of the Houghton Highway started in the late 1990s. The issue was agitated every time a crash caused delays, with the closure of one or two lanes or the entire bridge while the scene is investigated then cleared-up. Similarly, vehicle breakdowns on the bridge blocked lanes, also causing congestion and delays.

Tidal flow upgrade

The upgraded tidal flow LED lane control displays

Evening peak traffic arriving into Redcliffe

To dispel the public concerns, the Department of Main Roads ordered an upgrade of the bridge's tidal flow system. Commissioned in 2002 at a cost of $1.8 million, this upgrading included the replacement of the overhead arrow and cross signals with brighter displays, monitoring of traffic flows and conditions with supervision of the system data and view of the bridge by CCTV at the remote Traffic Management Centre in Woolloongabba, Brisbane. Operators were for the first time also able to close and open lanes as required from the remote location.

The upgrade project suffered delays from "technical issues", compelling the Transport and Main Roads Minister, The Hon Steve Bredhauer, to thank Redcliffe residents for their patience. Just six months later, the minister apologised for extensive delays after the system failed when a council contractor cut both the main and back-up power supplies to the tidal flow system just before 10:00am. Evening peak hour traffic was severely disrupted and banked-up for several kilometres as the bridge fell into "safe mode" with just one lane open in each direction for over 10 hours until Energex reconnected power at 8:00pm. Changes implemented after this incident included a better back-up power supply that was separate from the main supply, tighter controls on works near the bridge requiring approval by the Department of Main Roads first, and a variable message sign on the Gateway Motorway at Deagon to warn motorists of delays and suggest taking the longer, western route to Redcliffe via the Bruce Highway.

Reduced speed limit

Another initiative to stop debate over a new bridge was the reduction of the speed limit from 80km/h (49.7mph) for most of its length since the highway was built, to entirely 60 km/h (37.2 mph). The reduced speed limit also included a 500 m (1640.4 ft) approach to the southern end of the bridge along mostly 90 km/h (55.9 mph) four-lane Deagon Deviation dual carriageway. This 500 m approach was previously 80 km/h along with the bridge, and became 60 km/h with it. The professed reason behind this reduced speed limit was to reduce crash incidents, therefore reducing delays and blockages.

This reduced speed limit was initially a trial for nine months from September 2003 until June 2004, then a further unexplained six months. The City of Redcliffe moved in a General Purposes Committee meeting on 8 October 2003, that it can not support a 60 km/h speed limit trial, and requested to the Minister for Transport and Main Roads that the trial period be reduced to just three months. The minister replied committed to the nine-month trial.

In late November 2004, the state government declared the trial a success, using crash data that allegedly showed only three crashes in the nine-month trial period. The data did not include vehicle breakdowns on the bridge that would have involved delays from blocked lanes and, if possible, the overriding of the tidal flow system to manoeuvre traffic around such incidents. Just weeks before the permanent speed limit was announced, a severe four-vehicle crash with a motorist trapped in her car closed the bridge in the evening peak for three hours, and again caused banked-up traffic for kilometres and forced motorists to take the longer western route via the Bruce Highway.

Numerous reports and letters to the local Redcliffe and Bayside Herald newspaper from people complaining about tailgating and motorists speeding past, point to that the reduced speed limit is not being adhered. The tidal flow system's monitoring data has shown the average speed travelled on the bridge is actually 70 km/h (43.5 mph), 10 km/h in excess of the signed limit said to be the reason for fewer crashes.

Government rejections and about-face

Labor's Ray Hollis won the seat of Redcliffe in 1989 with the election of the Goss government and, except for a slim 0.5% lead in 1995, the seat of Redcliffe built-up with a safe Labor majority of 13.7% in 2001.

Continuing disquiet about the bridge, and calls for it to be duplicated or replaced, were persistently rejected by the government – a media statement titled "Call for second bridge rejected" was issued by the Transport and Main Roads Minister on 11 July 2003. However, in only three months time the Queensland Premier, The Hon Peter Beattie, issued a statement announcing a study into when a new Redcliffe bridge might be built. A reason for this change of stance included campaigning by the Redcliffe City Council and a study they commissioned into the duplication of the bridge, frustrated by the apparent lack of interest in the matter by the state government. In addition, just over two months later, a state election would be called, earlier than anticipated.

In this 7 February 2004 election, the rival Liberal candidate, Terry Rogers, campaigned heavily for a new bridge to Redcliffe, and Hollis, the Labor incumbent, suffered a 10.5% swing but held on to the now-marginal seat. Suddenly a new bridge became a need for Redcliffe.

In the next year, Hollis became involved in two scandals and the opposition called for his resignation. When the state government announced the duplication of the Houghton Highway in April 2005, the opposition suspected that Hollis was going to resign and stepped-up their campaign. Hollis resigned for health reasons in July triggering a by-election, and the promise of a new bridge was a solid commitment on both sides; the government announced it had already started the survey and public consultation phase. The Liberal candidate, once again Terry Rogers, won the 20 August by-election, while Labor won the seat back in 2006.

Bridge duplication

Template:Future bridge The duplication is the first bridge in Australia designed to withstand Hurricane Katrina-type storm events. It is also possibly the only Australian bridge which may have to deal with shallow water storm surge. The duplication will incorporate two traffic lanes, a bus transit lane, a 4.5m wide pedestrian and cycle path connecting with existing cycle networks on either side of Bramble Bay, and a fishing platform near the Pine River channel. This differs sharply from the original plan which was for a similar structure to the existing. The cycleway will be separated from traffic by a concrete barrier, thereby being much safer. The existing bridge will be converted for three lanes of northbound traffic, with the new bridge carrying southbound traffic. The original plan called for the new bridge to be constructed between the exiting bridges, but was amended to have the new bridge constructed on the Moreton Bay (eastern) side of the existing Houghton Highway. Increases in the cost of construction materials and labour; changes to the scope of the project following technical investigations and community consultation; extra costs associated with the removal of the Hornibrook bridge; as well as changes to reflect post-Katrina design, means the total cost are projected to be $315 million, compared with the $149 million estimated in 2004.

It was hoped that tenders for the construction would be called early-to-mid 2007, and construction from late 2007 until mid 2010 but the preliminary design went on display in June 2007.

The old Hornibrook bridge entry portals on both the northern and southern foreshores will be maintained to preserve the cultural heritage of the area. Timber from the existing Hornibrook Highway bridge will be re-used to maintain a section of the bridge on the northern Redcliffe side.

External links

• Houghton Highway Bridge Duplication project by Department of Main Roads