Civil Engineering October 2021 | Vol 29 No 9

Civil Engineering October 2021 5 effort that took several attempts before the team succeeded in crossing the river. 12 m deep jacking pits were first con- structed on either side of the river before a 1 m diameter concrete sleeve was bored beneath the riverbed. The concrete sleeve was then grouted in place and the 750 mm diameter pipeline pushed through it to complete the process. A similar approach was deployed to cross the N1 highway, while smaller pipe jacking operations were used at other road and railway crossings. This trenchless technology proved to be very effective in mitigating the impact of construction operations on the surrounding environ- ment. Although a significant challenge, the construction team adhered to very strict environmental controls throughout the works programme. Gaining the necessary permission to access the many properties through which the pipeline travelled was also a complex undertaking and the task had to be carefully managed to avoid delaying the works programme. QUALITY PIPES The pipeline was delivered to site in 18 m lengths which were then welded together by M&D’s team of welders who are certi- fied by the American Petroleum Institute. A dye penetrant test was used to in- spect the quality of all the welding joints which were then sealed with a coating to prevent corrosion. The cement-mortar lining inside the pipe at every joint was also restored after welding. As part of quality control, M&D kept a record of the block and chainage of every pipe, as well as the number of the joints and the welder who completed the weld, in addition to the date that it was un- dertaken. This documentation was then submitted to Magalies Water Board. M&D sourced the 3-LPE pipes from Hall Longmore. The first fusion bonded epoxy layer inside the pipe protects against corrosion. A second layer, consisting of copolymer adhesive, offers sound chemical bonding to the fusion bonded epoxy layer. The third, comprising polyethylene, also bonds well and seals the two layers. Elbows and joints for the pipeline were manufactured at M&D’s pipe fit- tings factory and sent to Hall Longmore where they receive their internal coating layers. This facility helps the Pipelines Division fast track the manufacture of steel pipeline connections and fittings of up to 3 m in diameter. Notably, it was one of the first of such facilities to be certified to ISO 3834 quality standards by the South African Institute of Welding, the International Organization for Standardization’s (ISO) authorised na- tional body for company certification. COMMUNITY DEVELOPMENT De Coning is proud of the fact that the project has also had a significant positive socio-economic impact on the two commu- nities located within the extensive project footprint. This is an important focus point for Magalies Water Board on all its infra- structure projects, including the Moretele South Water Supply Bulk Pipeline. M&D hired all its ancillary plant and equipment from small, medium and micro enterprises (SMMEs) to ensure that it was able to meet its enterprise development targets on this contract. This is despite M&D’s Plant Division owning all equipment required for this project in its large fleet to complement its state-of-the-art pipelayers that were deployed to work on this project. Moreover, many employment and training opportunities were created for community members throughout the construction programme. Approximately 120 locals worked alongside M&D’s team when the project peaked between November 2020 and February 2021. Up to 30% of the total value of the con- tract was designated to socio-economic and enterprise development. To further demonstrate its commitment to previ- ously disadvantaged communities located within the project footprint, M&D paved a 1.8 km gravel road in Hammanskraal to help uplift the area. “This is yet another example of how M&D implements its Khula Nathi motto on our worksites. We have a very good reputation for being able to work well with emerging contractors, SMMEs and people who we employ from communities. This includes being able to manage the expec- tations of communities within our project footprints to mitigate work stoppages on our contracts. This ability also acted in our favour when tendering for this project and helped mitigate disruptions on the worksite,” says De Coning. Certainly, working with eight dif- ferent wards, each with their own project steering committees consisting of coun- cillors and community liaison officers, was a complex undertaking that had to be carefully managed to avoid delays in sourcing equipment and labour for the works programme. Rukesh Raghubir, CEO of M&D, says that he is proud of his team’s exceptional performance for a longstanding client. “I am confident that we will have the opportunity to work with this leading pro- vider of water services to Water Services Authorities, Water Services Institutions and other users in the foreseeable future. The water infrastructure solutions that we provide water boards, municipalities and mines complements the skills that our Pipelines Division continues to hone while also delivering cutting-edge construction services to the petrochemicals and gas industries,” concludes Raghubir. For more information www.mdconstruction.co.za +27 11 463 1962 info@mdconstruction.co.za The pipeline traverses under­ ground along the entire route