Rates to pay for damage
Thursday, 28th April, 2011
By Gayle Hogan
Repairing a section of road in Thomas Street, which failed less than 12 months after it was laid, is expected to come at a cost of almost $200,000.
Record rainfall over an extended period of time has been blamed for the damage.
A report to City Council said a preliminary estimate of remedial works to repair the road was put at $184,000.
The new road, adjacent to the hospital between Chloride and Bromide streets, was laid in 2009 to allow for more parking spaces but within 12 months the smooth new surface began to crack and split.
"Over time a number of pavement failures have become evident over the entire length of the (road) pavement and water is seeping from various fissures and cracks," the report said.
Council has since conducted a three-phase review of the works which included a physical inspection, document review, inquiry and testing.
"The results of the review indicate that the probable cause of the road pavement failures was caused by ground water infiltration into the subgrade and pavement material reducing the overall strength of the pavement," the report said.
"This caused excessive stresses in the hotmix layer resulting in the alligator cracking.
"The recent consistent wet weather that has resulted in near record rainfall over an extended period of time was not predicted.
"Hence the potential adverse results of such weather conditions on the road pavement were not foreseen either during the design or construction stages."
Council is recommending that subsoil drains be installed to intercept the ground water and reduce the amount of moisture getting into the base, sub base and subgrade.
The issue will be considered at next week's Council meeting.