ROADS & BRIDGES
Small town road upgrades strengthen their economies Situated on the Garden Route, Great Brak River is a bustling coastal town and popular seasonal tourist destination. As with any urban space, the town’s commercial and residential mix has evolved over time, influencing current and future town planning requirements, as well as the need to reconstruct key road networks.
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he town falls within the jurisdiction of Mossel Bay Municipality (MBM), which recognised the need for an extensive upgrade of two key routes, along with improved safety for parking and pedestrians. The works entailed the rehabilitation of Long Street and Stasie Road (MR348), and the upgrading of Sandhoogte Road, with design and construction supervision carried out by SMEC South Africa’s George office. “Over the years, the town of Great Brak River developed around the MR348, and the road’s cross section was never formalised,” explains Altus Eitner, a professional engineer in the Streets & Stormwater Department at MBM. “One of the objectives of the MR348 upgrade was to implement a standard cross section and to restore the pavement to Western Cape Provincial Government (WCPG) standards. We also recognised that due to the area’s high water table, constant patching and pothole repairs were proving to be ineffective, and the increasing deterioration of the road required a full rehabilitation,” he continues. Valued at approximately R47 million, works commenced in February 2020 and were completed in March 2021. The MR348 roadworks phase was 80% funded via the WCPG Maintenance and Construction
of Transport Infrastructure Grant, with the remaining 20% financed by MBM. MBM provided the funding for the town’s upgraded sidewalks (totalling some 4 600 m), which included wheelchair access points, upgrading sections of Sandhoogte Road, and the construction of a new traffic circle at the Amy Searle intersection. “An important point to note is that provincial funding models place a key distinction between a rehabilitation and rebuild application submitted by a municipality. The first provides funding for surface repairs (between kerbs). In contrast, a rebuild application covers the bulk of the costs, so it’s essential for municipal engineers to be very specific about their funding requirements,” Eitner explains. As part of the contract, 108 local unskilled labourers were employed via the MBM shakeshake system (effectively a lottery process for the fair selection of qualifying applicants), all of whom were drawn from surrounding residential areas. In total, 86 individuals received stop/go and/or flagman training.
Key construction phases The rehabilitation of Long Street and Stasie Road, measuring 2.56 km in length, entailed: base patching and edge break repairs; crack sealing; the replacement of a damaged culvert; bridge maintenance; new kerbs and channels; stormwater upgrades; and a
40 mm medium A-R2 (bitumen-rubber) asphalt overlay. The asphalt was supplied by AECI Much Asphalt in George and amounted to some 2.6 tonnes. “Approximately 70% of the MR348 is constructed below the 1:50-year flood line, so the original road design was outside the current recommended design standards. SMEC’s pavement rehabilitation design allowed for pavement strengthening in those sections worst affected by water ingress, as well as minor level corrections. Overall, we decided to leave the sub-base undisturbed, based on geotechnical investigations,” says André Delport, professional technician: Roads and Highways, SMEC. Prior to construction, some 40% of the sidewalks within the town were gravelled shoulder sections. In-between maintenance intervals, these became rutted and contributed to ponding. The lack of a hard edge also resulted in edge breaks along the road. Adding kerbs and paving sidewalks in a uniform colour was a definite aesthetic and safety improvement, and contributed to more effective stormwater management. Works on Sandhoogte Road, measuring 380 m in length, entailed an upgrade from a gravel to asphalt surface. This comprised the construction of new layer works, stormwater improvements, and surfacing with a 30 mm medium A-E2 (elastomer modified) asphalt layer. The road is a strategic one as it supports heavy vehicles from surrounding farms and a quarry.
Business rights and traffic accommodation “During the MR348 upgrade, traffic accommodation needed to be carefully managed since this is the only road passing
The new traffic circle at the Amy Searle intersection
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IMIESA August 2021
