July 24, 2014

The Demerara Harbour Bridge: A floating wonder

By Danielle Campbell

The Demerara Harbour Bridge

Though taken for granted by many, the Demerara Harbour Bridge (DHB) is a basic necessity for thousands of commuters on any given day.
Spanning Peter’s Hall on its eastern edge and Schoonard/ La Grange on the western edge, the bridge is a vital, linking spanning the east and west banks of the Demerara River. Persons living in the Essequibo communities and beyond also utilise the bridge to access the capital city and other areas in eastern Guyana.
Considered one of the world’s longest floating Bridges, the harbour bridge was established in 1978. The bridge consists of 61 spans of varying lengths and floats on 122 steel pontoons.
A number of buoys are attached to the structure and serve as a safety measure in case of persons accidentally falling overboard. Described as a majestic landmark, the 6074- foot floating toll structure was opened to the public on July 2, 1978.
Attached to the bridge is a walkway which is used by pedestrians for various reasons. Sightseers, tourists, and lovers spend many leisurely hours on the walkway while health enthusiasts use it as an exercise footpath. The bridge’s walkway is seen as a recreational outlet from where the public views the awesome fireworks display by the Guyana Defence Force on holidays.

Retractor span
The harbour bridge is an awe-inspiring sight as the central section is retracted each day to allow oceangoing ships and other large vessels to pass. During the retraction, vehicular traffic is restricted for a period of about one and one-half to two hours. The harbour bridge, which was initially given a lifespan of about 15 years, is crossed by an average of 16,000 vehicles per day in both directions.
The DHB was rehabilitated during the 1994-1997 period and was given a second lease on life for another 15 years. According to General Manager Rawlston Adams, this does not mean that the bridge has outlived its usefulness, as with the requisite maintenance, its life can be further extended.
Adams explained that although commuters are requesting a new bridge, he believes that this has more to do with the capacity of the bridge given the increased volume of traffic. He acknowledged that rapid housing development, the presence of more vehicles on the road and increased business investment in Region Three are just some of the factors which contribute to traffic congestion in recent years.
However, management has taken a very proactive approach and has implemented many effective measures to ease this congestion, including halting the collection of tickets at the western end of the bridge.
Adams has also implemented a double-lane system whereby traffic is allowed to proceed on both lanes in the same direction for about 15 minutes twice per day.
The general manager disclosed that the double-lane system is currently under review and will most likely be rescheduled to 07: 00h.
He explained that utilising the double-lane system in the evenings have proven much more difficult to coordinate since the peak hours vary, with school being dismissed at 15: 00h and employees’ work days coming to an end at 16: 00h, 17: 00h and 18: 00h.
“This double-lane would tend to fluctuate depending on what time of the evening it is,” Adams noted.
Over the years, the bridge has been subjected to heavy traffic and over-laden vehicles which have contributed to its wear and tear.

DHB General Manager Rawlston Adams

As such, management has placed a restriction on vehicles weighing in excess of 22.4 metric tonnes, facilitating special crossings for vehicles beyond this limit but not exceeding 35 tonnes.
These vehicles are allowed to cross, once 24 hours advance notice is given to the bridge’s management.
Adams revealed that there has been an increased demand for special crossings.
Heavy vehicles and speeding which result in the dislodging of the deck plates have always been major causes of concern for the bridge management.
Since the deck plates are manufactured from smooth steel, the bridge was asphalted to prevent slippages and accidents especially when it rains.
That project has been successful and several damaged plates were replaced on the various bridge spans identified for resurfacing.
Continuous maintenance and rehabilitative works on the existing structure has been an ongoing process to ensure a safer and more reliable service.
“Our mandate is to effectively maintain this structure and to ensure it is accessible to traffic for the movement of goods and people on both sides,” Adams stated.