Ministry of Works and Transport has said that the reopening of the old Nalubaale bridge does not pose any safety threat to road users because the infrastructure is still strong and durable.
Uganda National Roads Authority (UNRA) will from next week April 15 through to July 10, close part of the recently commissioned Source of the Nile Bridge to allow for restoration works to replace the defective pavement and asphalt layer.
During the works, some of the traffic will be redirected to the old Nalubaale bridge that had been closed to motor vehicles since last year. Only the Kampala-bound traffic will allowed on the new bridge while Jinja-bound traffic shall be diverted to the Nalubaale bridge.
The Nalubaale bridge was initially declared weak, according to periodical studies conducted more than a decade ago. The bridge was constructed in 1954 and had reportedly outlived its lifespan.
Despite the safety concerns, state minister for Works, Gen Edward Katumba Wamala says that the old bridge was never condemned and it is still strong enough to serve the purpose.
The old bridge survived without major repairs since it was established except in 2011, a process that continued to 2013 with tarmac and road surface being fixed. The new Source of the Nile bridge developed surface defects 10 days after it was commissioned on October 17, 2018 drawing public outrage.
The Observer recently exposed how the asphalt layer on the 120-year bridge had once again peeled off in less than a month after being restored.
The latest scope of works will include an application of a waterproofing material to the concrete deck surface that will effectively bond with the modified polymer asphalt layer, according to a statement issued by UNRA last week. The works will be undertaken through a Joint Venture of the Zenitaka Corporation and Hyundai Engineering and Construction Co. Ltd.
According to UNRA project engineer Morris Odru Odoch, the cracks and rutting were observed on October 20, 2018, just three days after opening the bridge to traffic on October 17, 2018. He says that the sudden defects resulted from the lack of bonding between the waterproofing materials and asphalt used on the surface of the bridge.
"Due to lack of bond, the asphalt surface was unable to withstand the shearing force of the passage of traffic," said Odoch in a recent interaction with MPs on the Physical Infrastructure committee.
Odoch assured MPs that the Source of the Nile main bridge structure has been designed for a period of 120 years and has no single defect save for the cracked outer layer.
Source