Civil Designer Showcase

Challenges With The Addo Elephant National Park

"THE Addo Elephant National Park project is perhaps one of the most challenging yet rewarding ventures that I have had the privilege to work on," says Africon PE engineering representative, Graham Webster. The project was recently completed with funding received from the Department of Environmental Affairs and Tourism, and entailed the upgrading of existing roads in the Park.

"The various project participants include Vuka Project Management Services, appointed by the SA National Parks to implement the project, George based contractor ACV Civils, and Africon as project consultant. The finalisation of the venture, estimated at a cost of R19,5 million, has seen the realisation of two important objectives: that of job creation, and tourism development," says Graham.

Africon was tasked with the re-design and monitoring of the existing road upgrade and construction, to formation level. "The access road comprised of a new 30km southern access road from Colchester in the south over Addo Heights, to link up with the Parks existing road system in the main tourist attraction area to the north."

"Approximately 28km of road was upgraded to a gravel surface, while a total of 14km of bitumen-surfaced roads were up-graded in the park's existing game viewing area," explains Graham, adding that the upgrade of the roads has allowed for uninterrupted business flow, as roads no longer have to be closed due to rainfalls that exceed 8-10mm.

Design Challenges
According to Graham, South Africa has a total of seven natural biomes - self-sustainable areas in terms of the earth's natural environment - and five of these biomes are found at the National Addo Elephant Park. Animals in the "big five" area include elephants, often within ten meters of a work team, while the introduction of lion into the park in September 2003 held a further complication with regard to safety arrangements.

Apart from the fauna, the park's flora was equally challenging during the design. "Determining the horizontal alignment of the new southern access road was difficult with the impenetrable bushveld valley. We therefore had to clear the undergrowth on the 30km new access road with the use of manual labour."

In addition to the actual terrain, the project itself presented some interesting design challenges. "We had to establish a winding road, so that visitors at the park could anticipate what was around each bend and not see a lot of cars up ahead. Although this helped to create the feeling of being alone in the "bush", it was quite difficult for the team to spot any oncoming dangers up ahead while working," says Graham, explaining that when they dealt with the vertical alignment, they had to ensure that it could accommodate buses while still minimising the amount of cut to fill.

"We completed the design almost on an ad-hoc basis and would roughly sketch a route on the map and then tweak it according to the client's needs before the alignments were entered onto the computer. We constantly had to adjust the design in order to meet the criteria of the client."
 
Addo Elephant National Park | Africon


"This is where a program like CIVIL DESIGNER is particularly helpful, as it could handle our numerous changes with absolute ease. In theory, we could do the design on site on a laptop, draw in the design criteria, survey it and then peg points according to requirements."

"We found that one of the requirements of the poverty relief program that supplied the projects funding, was to select appropriate construction methods that would generate the maximum number of employment opportunities."

"The project required manual labour for drainage and drainage structures, the finishing and trimming of road verges, landscaping and planting work, as well as the manual collection of discarded railway ballast from alongside the Addo Patterson Railway line. We used the ballast along the railway to improve the CBR of the calcrete material that was used as a sub-base layer for the bitumen-surfaced roads," explains Graham.

The project's final challenge was to identify and obtain permission from the Park's Management for the borrowing of suitable road building material for the project. "We identified three calcrete quarries and one Table Mountain quatzitic quarry through material testing, and then obtained environmental approval in order to establish a crushing plant at one of the quarries, in order to produce a G4 base cover using the Table Mountain quatzitic sandstone."

Graham's experience on the project is summed up by the following words: "I was extremely privileged to have worked with excellent team mates during the project's completion, and I would like to acknowledge the invaluable contributions of Joubert Nel (Africon), Andre du Plessis (SANParks - Cape Town) and Lucius Moolman (SANParks - Addo. It is always an enriching experience to share the rewards of months of hard work with such special people."

image Graham Webster completed his National Survey Diploma at Pretoria Technikon. In 1968 he was a pupil technician for the Cape Provincial Roads Department in Cape Town, he then joined the PE Divisional Council in 1971 where he worked for 21 years, and then became the Chief Roads Technician at the Western District Council PE. After accepting a retrenchment package offered by the Western District Council in 2000, he worked as the Engineer's Representative for Africon on the upgrading of the Oyster Bay/ Palmietvlei and Addo Elephant National Park Road Projects.

 
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