GUYANA – $350m Hope Canal Bridge defective
GEORGETOWN – Two years after the Hope Canal Bridge on the East Coast of Demerara was commissioned, it continues to cause great inconvenience to road users. However, the problem can be narrowed down to the fact that not enough thought was put into the design of this multimillion-dollar structure.
This opinion was expressed Thursday by highly experienced Geotechnical Engineer, Terrence Fletcher.
The eastern and western approaches of the $350M structure have been sinking, resulting in officials now scrambling to rectify the problems. Road users have also been registering their concerns – deeming the depressions leading up to the bridge as a major traffic nuisance and a hazard to motorists.
Fletcher, who has over 50 years experience in the field of Geotechnical Engineering, said that based on his observation, he can only come to the conclusion that the consultants did not cater for the amount of settlement that would take place after construction. Fletcher said that he does not know what the consultants were thinking. He explained that most bridges, drains and seawalls along the coast are built to a certain height in accordance with the Georgetown Datum (GD). The GD, he explained, was derived after a lot of discussions, and experiences with flooding in the city.
Experts came up with some information to establish a level for various structures. For example, having established the GD, engineers should know that the streets of Georgetown should not be less than 52.5 feet above the datum of zero which is below the surface of the earth, he said.
“To make it practical, they actually have a mark on the lighthouse which is somewhere at 55 GD, so you can either measure up or down from that . . . a convenient mark, and so for our highways on the coast, the general level is 54, and for the Hope Canal Bridge, [it] is 58. So it’s higher than the average bridge.”
Fletcher explained that because of this uniqueness, the approaches should have been on piles.
“The Hope Bridge is okay. It has been built on piles. The problem exists with the approaches; the embankment going up to the bridge is not on piles and that is settling. They [authorities] have been adding asphalt to bring it back to the level,” he said.
“This may or may not solve the problem,” Fletcher said. He added that “it still needs to be determined whether the approaches are settling normally”.
Asked what his recommendations were, Fletcher candidly asserted that “not much can be done at this stage”. He is however urging that the authorities continue doing what they are doing until the settlement comes to a stop, which may be within two to three years.
The bridge is 74.4 metres long and has 47-metre sloped approaches on each side; it has the capacity to accommodate two-lane traffic, with sidewalks on both sides. It was constructed by DIPCON Engineering Company and commenced in 2011. The completion date was rescheduled from July 2013 to end of August of that same year.
However, as a consequence of several “setbacks” the completion date was subsequently slated for December 31. The bridge was completed several months later.
Minister of Agriculture, Noel Holder, a few weeks ago had stated that the faulty bridge was a result of politicking and poor design.
The bridge was part of a four-component project that was the brainchild of the former administration – the People’s Progressive Party/Civic.