Mtentu Bridge: Africa’s Tallest and Longest Cantilever Bridge

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Mtentu Bridge is one of the significant infrastructure investment projects that the South African government is implementing in the country present in its current construction phase in the course of implementing the N2 Wild Coast Road (N2WCR). This project involves the construction of new road infrastructure to improve the transport link between the Eastern Cape and KwaZulu-Natal Provinces in South Africa The South African National Roads Agency Limited (SANRAL) is responsible for the implementation of this project. It will be the tallest bridge in Africa and one of the longest main-span balanced cantilever bridges in the entire globe. It is part of a larger program called N2WCR, which the South African government categorizes as a Strategic Infrastructure Project.

Location

The Mtentu Bridge is located over the Mtentu River on the Wild Coast of the Eastern Cape, which is characterized by steep cliffs and picturesque scenery. The bridge shall cross the Mtentu Gorge, with the height of up to 223 meters and the main span of 260 meters. Once it is finished, the bridge will not only be a part of unique architecture and a great engineering marvel but also African record-breaker, with a status of the tallest bridge in Africa.

Construction and Engineering

The construction of the Mtentu Bridge is being undertaken by the China Communications Construction Company (CCCC) in partnership with MECSA Construction Company. The project was awarded back to this joint venture in November 2022 after the construction stopped in 2018 due to protests and contractual issues. Total cost estimate for the bridge is R4. 5 billion which is about 270 million dollars and the construction is expected to end in December 2027. The bridge forms part of the N2WCR project, which is about 410 km long transport corridor starting from East London to the Mtamvuna River at the border between the Eastern Cape and KwaZulu-Natal provinces.

Mtentu Bridge

The bridge will be designed using the balanced cantilever method, which is effective in construction of long span bridges in hard landscapes. This method involves constructing a bridge deck which is then projected forward from two piers located on both ends of the gorge, and when joined together at the middle they make the bridge span. The design and construction of the Mtentu Bridge have been applauded for its ingenuity and intricacy for the challenging landscape of Wild Coast.

The Mtentu Bridge is not just an engineering marvel; it also holds a prospect of yielding numerous socio-economic returns for the area. The construction is expected to generate 1800 full-time employment opportunities which preference shall be given to residents within the local region. The projectโ€™s contract requires that 4 percent of the total projectโ€™s cost or about 141 million Rand be spent on wages and salaries for local employees.

Economic and social impact

This shall be carried out as a strategy to promote economic development and job creation within the Eastern Cape. Similarly, the N2WCR, which encompasses the Mtentu Bridge, intends to reduce the time required to travel to the Wild Coast area besides boosting the economic sector, tourism, and trade within the region.

The road is also part of the governmentโ€™s over strategic infrastructure projects (SIPs) that have been adopted to ensure that growth and development of the underdeveloped regions of the country is boosted. Due to its location in a sensitive environmental area, the Mtentu Bridge project also incorporates sound environmental and social impact studies. Local communities and other stakeholders have been consulted throughout the pre-planning and construction of the project by SANRAL. Procedures have been implemented to reduce the effects on the environment in the locations where the mining operations are located with regard to local species and their natural habitats.

 

Also included in the project is the construction of the three community access roads and extension of the provincial road network by 18 kilometers; in essence local communities will benefit from improved access to facilities and services.

 

Project Challenges and Timeline

Since the onset of the construction of the Mtentu Bridge, the project has been subjected to a number of challenges such as the protest on the construction and the recent cancellation of the initial contract in 2018. Yet, construction has begun anew, after the re-award of the contract in mid 2022 and the project is expected to be delivered in mid 2027. Depending on the construction phase, it appears that the following construction activities are in the pipeline: mobilization phase, site clearance, and progressive construction whereby most of the construction work of the bridge structure is expected to commence within the next few years.

Mtentu Bridge tender in South Africa awarded

In 2017 South African National Roads Agency SOC Ltd (SANRAL) awards the highly anticipated tender for the Mtentu Bridge. SANRAL has awarded the project to the Aveng Strabag Joint Venture (JV).

The venture consists of Aveng Grinaker-LTA, a major South African-based construction company and Strabag, a leading construction company in Europe with extensive experience in major balanced cantilever methodology bridge construction.

Construction of the US$123.7m project is set to start in early November 2017 and take approximately 40 months. The tender forms part of the N2 Wild Coast road (N2WC) project.

Also read:ย Platjan bridge construction in Botswana starts

A first for SA

As the first of its magnitude in South Africa, the Mtentu Bridge is one of the longest main span. Moreover, the project is balancing the cantilever bridges in the world and will reach heights of approximately 220m.

โ€œCritically, it is going to create employment and business opportunities in the area. The whole of the project will be a growth engine for the Eastern Cape both during and post construction,โ€ Vusi Mona, SANRALโ€™s Communications Manager said.

Also read:ย Botswana-Zambia bridge construction project on track officials say

However, the construction of the 1.1km long bridge in a remote location is a major undertaking that requires specialized engineering skills and building techniques.

According to the roads agency, the bridge forms the backbone of the greenfields portion of the N2WC road. The project is a national priority under coordination and direction of the Presidential Infrastructure Coordinating Commission (PICC) and one of governmentโ€™s 18 Strategic Integrated Projects (SIPs) to support economic development and address service delivery in the poorest provinces.

Also read:ย Nigeriaโ€™s Lagos 4th mainland bridge set for construction

Improving travel time

The entire project will play a vital role in improving travel time, connecting previously divided communities in the region. Also business opportunities and community-based tourism for the Wild Coast will get boost.

The route will have significant social and economic benefits. Nonetheless, the bridge will act as a catalyst for local and regional development,โ€ said Vusi Mona.

SANRAL says Mtentu Bridge will be built

In 2019 South African National Roads Agency Limited (Sanral) through the organization’s engineering executive Louw Kannemeyer said that Mtentu bridge whose construction came to a standstill in early February will resume on an unknown date.

The Avengย Strabagย joint venture (ASJV), which clinched the contract in 2017 and was to deliver it in May 2021, terminated the US $115.5m bridge contract located in theย Eastern Cape claiming that it had been unable to work on theย projectย site since October last year due to continued violent protests related to job and contract demands made against Sanral by locals.

However Sanral believes that the situation had been stabilized, following a community level intervention, for the contractor to resume work.

Also Read:ย Zambia set US $1.7m to repair Lunzuwa Bridge

SANRAL to seek a new contractor

As of now Sanral and ASJV are locked in a legal process related toย projectย guarantees. โ€œWe will have to see how the legal process unfolds before we can decide the way forward,โ€ says Kannemeyer. โ€œThe legal process will determine the mechanism used to appoint a newย contractorย for theย Mtentu Bridge.โ€

Kannemeyer believes that other international firms will be willing to travel to theย Wild Coastย to build the structure although he also acknowledges thatย buildingย theย Mtentu Bridgeย is not an easy task.

The twin support towers of the bridge will be higher than Carlton Centre, currentlyย Africaโ€™s tallestย building. The Towers of the bridge are approximated between 55 and 60 storeys high, withย constructionย teams thenย buildingย the bridge deck from these towers. Considering the height of the towers, as well as the fact that the bridge crosses a gorge, dealing with high winds may prove particularly challenging.

Sanral believes the complexity of theย projectย will result in a new, extended tender period of at least five months. To compile a new tender, go through the tender process, adjudicate, award, obtain the necessary labour permits, mobilize and establish on site, is likely to take at least 12 months.

Legal issues may extend this period even further.

Construction works on US $4bn Mtentu bridge in South Africa halts

By March 2019 construction works on the US $4bn Mtentu bridge US $4bn Mtentu bridge had stopped following Construction company Aveng terminating itsย contract with the SA National Roads Agency Limited (Sanral) to build the bridge.

The decision follows violent protest action against the project, which entails building the 1.1km-long bridge across the Mtentu River on the N2 Wild Coast. With the nearby Msikaba Bridge, the Mtentu Bridge is part of an improvement to make the N2 Wild Coast toll roadย shorter and faster.

Also Read:Senegal inaugurates the new Senegambia bridge

Community unrest and protest action

The construction company which isย a joint venture with Europe-based Strabag International, saidย contractors have not been on site since October 22 due to threats of violence and levels of community unrest and protest action related to demands made against Sanral.

โ€œThe joint venture does not agree with Sanralโ€™s view and related events do not support Sanralโ€™s view. The ability to execute works safety and in accordance with international best practice is our primary concern,โ€ said Aveng.

โ€œThe construction of the Mtentu Bridgeย is technically demanding and requires compliance with the most stringent international engineering and safety standards, with zero margin for the disruption of the nature experienced,โ€ย added Strabag spokesperson Diana Neumรผller-Klein.

Upon completion the bridge is set to beย one of the longest main-span balanced cantilever bridges in the world, and will reach heights of around 220 m.

Construction of the R4.05bn Mtentu Bridge begins

In August 2023 The South African National Roads Agency SOC Limited (SANRAL) announced about the commencement of construction work on the significant Mtentu Bridge contract. This follows a four-month mobilization phase which began on April 5, 2023, and concluded on August 4, 2023.

The contract for the Mtentu Bridge was granted to the China Communications Construction Company (CCCC) and MECSA Construction joint venture (CCCC MECSA JV) on November 1, 2022. The allocated budget for the Mtentu Bridge contract is estimated to be R4.05 billion. The construction of the bridge is expected to span 50 months, with a projected completion date towards the end of 2027.

“Throughout the mobilization phase, SANRAL interacted with stakeholders from both the Northern and Southern sides of the Mtentu Bridge. The local stakeholders have received information about the contract being re-awarded with enthusiasm and are eagerly anticipating the resumption of work after the project halt in October 2018,” explained Mbulelo Peterson, Southern Regional Manager at SANRAL.”

The height of the Mtentu Bridge

Once completed, the Mtentu Bridge will be the highest in Africa and one of the longest main-span balanced cantilever bridges in the world, with a main span of 260 metres at a maximum height of around 223 metres.

This week, a team of 15 general workers will initiate the construction of site offices, while 30 general laborers will undergo medical assessments and safety training. Afterward, they will engage in site clearance and grass cutting activities. Additionally, two recently qualified unemployed civil engineering graduates have been enlisted through the Project Liaison Committee (PLC) to contribute to this contract.

 

The commencement of borehole construction on both the North and South banks is scheduled for August 15. Following that, on September 1, activities including toilet construction, security installations, and the relocation of affected households will commence.

N2 Wild Coast Road

The Mtentu Bridge is an integral component of SANRALโ€™s N2 Wild Coast Road (N2WCR) initiative, encompassing a 410km road stretch from East London to the Mtamvuna River on the border between the Eastern Cape and KwaZulu-Natal provinces. Approved by the Presidential Infrastructure Coordinating Commission (PICC), the N2WCR program serves as a catalyst for economic advancement in the region and is part of the government’s 18 Strategic Infrastructure Projects (SIPS). The N2WCR, identified as SIP3, specifically targets South-Eastern node and Corridor Development, aiming to significantly stimulate economic growth in the Eastern Cape and KZN provinces.

The Mtentu Bridge contract has a local labour Contract Participation Goal (CPG) of 4%. This will see a minimum of R141 million (excl. VAT) being paid to local labour in wages and salaries, creating a minimum of 1080 full-time employment (FTE) jobs for local skilled and unskilled persons during the contract.

โ€œWe are excited about the massive socio-economic impact presented by the construction of the Mtentu Bridge in this region. Approximately 1 800 full-time equivalent jobs will be produced during construction. While numbers will vary during the contract, this equates to an average approximate number of 360 jobs created per month over 50 months, of whom about 300 will be for locals,โ€ added Peterson.

“The establishment of the Project Liaison Committee responsible for supervising the effective project execution and protecting the concerns of the nearby residents has occurred subsequent to its selection by community representatives in 2021. Peterson emphasized that this PLC framework will play a crucial role in guaranteeing the attainment of the 30% contract participation objective specified in the agreement and in securing advantages for the designated recipients.”