Civil Designer Showcase

Moving The River That Ran Through It

"We were busy moving this river just outside Witbank. The project was on an opencast mine and we had to divert the river around the 2km area to be mined. Someone then strolled in and announced that there would be a 'controlled flood' in five days. They said it was a regular occurrence and seemed quite amazed that we didn't know about it."

Adrian Skea is the Cape Town branch Manager of UWP Consulting. He has led an interesting and exciting professional life since qualifying as an engineer in 1987. "Cape Town has a different excitement, as I am involved in a lot of interaction with our clients and the ever-present bureaucracy. This can almost be as exciting as a flood," he says with a huge grin.

After spending his early career years working on projects in Ulundi and Lesotho, Adrian was transferred to a new JCI open cast coal mine in Witbank. "This was a strip mining operation using a drag line. The only unfortunate thing was that a river ran through the mining area. 'No problem' they said, 'just move the river.' So we built a dam at each end to stop the flooding on the strip. We planned to deviate the river by blasting and excavating a "new river" about 15m deep and roughly 40m wide around the strip, but a lot of water had to flow under the proverbial bridge before we finally achieved our objective."

"We had to build a huge reinforced earth retaining wall about six storeys high. That was actually quite interesting - as we had to divert the river under the main Richards Bay coal line bridge, and it had to go through ninety degrees under the bridge. The earth wall had to protect the bridge foundations and this was a huge challenge."

Then panic! "We had just built our two downstream coffers, and done the excavations down to bedrock and were about to put the clay core in when we were shocked rigid. We had been informed that a flood would come sometime, but no-one could tell us when."

"So we got our drill rigs out, blasted for three days, excavated using two CAT 245ís and two 35-ton dump trucks and finished with about four or five hours to spare." The laughter bubbles again. "Unfortunately, the blasting had fractured the rock in between, so when the deluge came, it flooded the excavation, so we should just have left it alone."

"After a stint on the Sasol One mine, I realised that I'd had enough of mining, so I joined Mike White at UWP in Cape Town in 1994. I have done a lot of work in Atlantis, Khayelitsha and out in the Winelands. When Mike got transferred to Joburg, I had to take over the Cape Town office."

UWP uses Civil Designer throughout their thirteen offices. Seventy-five percent of their employees are technical, but most of the design work is done in Johannesburg, Pietermaritzburg and East London. "It is excellent software," says Adrian.

The reconstruction of Jan van Riebeek Drive in Paarl brought about excitement of a different kind. This 2.1km road has taken nearly four years before the construction commenced. "The rehab investigation was done back in 2000. The intention was to reconstruct on the original alignment with either four-lane undivided, or dual-carriageway. In January 2002, a decision was made to go ahead with the detail design, and we were told to get on with it."
  "There are a couple of farms alongside this section of road. One of the farmers arrived and said, 'we have just paid R10m for this farm, and we can't have this road running just 20m from our front door.' We also had to consolidate their accesses into one to comply with the provincial guidelines."

"They then proposed that Jan van Riebeek Drive be moved further away from their front doors and agreed in principle to pay for the diversion. At the time however, the neighbouring farm was up for auction, so we had to wait for this to be finalised. In the meantime we conducted a series of public participation meetings. We also did a stage one scoping investigation, got the heritage consultants and the archaeologists in, and got the whole process going."

"Once the auction was concluded, the two farmers confirmed their offer to fund the additional costs of construction to move the road. Our cost estimate indicated about a million rand extra to relocate the road and electricity pylons etc. At that point we had done a preliminary design. Province eventually gave the go ahead to realign the road. They signed contracts with the farmers and we started designing."

The new design was duly finished, but the record of decision (ROD) took a further six months. Just before National Heritage was about to approve, a Provincial Heritage body was established. "So the ball was tossed to the new body who understandably took some time to find their feet. Finally in October 2003, the ROD was issued, which was promptly appealed by a neighbouring farmer during the statutory 30-day appeal period."

"The Minister of Environmental Affairs was then suspended, leading to yet another delay. The delays just never seemed to stop. We ended up with a R34 million budget for 2km of road, and only started the job in August 2004, the end of the wet Cape winter."

"The new road reserve was thoroughly soaked by a once-in-forty-year storm, leaving the ground really wet. The Bell dumpers got stuck, so the best solution was to simply re-program the work, extending the project by another month and half," he says ruefully.

"Life is definitely interesting as an engineer," says Adrian. With unexpected floods, prickly farmers, and public participation meetings, 'social' engineering skills are now a definite requirement. Adrian Skea continues to define the new role that so many civil engineers will have to adopt - and he still manages to laugh infectiously when the going gets tough.


 
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