Civil Designer Showcase

Water Wonder Works

THE history behind the Ngqusi bulk water supply project in the Eastern Cape began with a struggling community who were severely affected by limited water supplies in the area. As a result, many residents were forced to collect drinking water from nearby springs.

"This extremely poor community consists of either small scale farmers or residents that rely on government grants and pensions to survive. The rural Ngqusi area accommodates some 26 villages and has approximately 11 300 residents that live there," explains Francois Lyons from Africon East London.

"The idea of this project was to design an adequate water supply system that would meet the needs of 26 villages. Amongst others, this meant designing two pumping mains with a combined distance of approximately 10km and gravity and reticulation pipelines of around 127km. This would accommodate for a project demand of 309kl per day," he says.

Francois was responsible for the layout planning and design of the scheme. "The preliminary design for the scheme was detailed with the help of Civil Designer's Design Centre, Survey, Terrain, Roads and Water modules. The program helped us to produce the long section data of the topography which we exported from the program into spreadsheets where we did the preliminary calculations."

"The data was then imported back into the program in order to test the calculations before outputting the final product in the drawing package. I find that the different modules work together in a harmonious way and allow complete freedom when designing schemes like these," says Francois, clearly impressed by the programs capabilities.

"We used the Roads module to help us produce long sections in order to help position the air and scour valves for the pipelines. We also used the program to help grade the pipelines optimally to make use of the pipe's joint deflection so that we could prevent expensive bends in cases where large and costly diameter pipelines were used. In addition, we made good use of the Survey & Terrain module to convert our GPS readings to projected coordinates and to help produce coordinate lists for the layouts," he continues

The project required extensive use of data which was accumulated from maps, GIS and various aerial photographs in order to assist with the route planning for the pipelines. "We co-ordinate the plans in AllyCAD and then make use of Civil Designer to insert the bend points. GPS co-ordinates are also used to determine the exact position of specific obstacles. It is great to systematically build up your model and then see the final product unfold on screen. I enjoy working with the program and all the modules are extremely effective."
 
Ngqusi bulk water, Eastern Cape | Africon


During the project, the team had to avoid sensitive vegetation and wetland areas. "When we came across environmentally sensitive zones, we had to re-route the pipelines to prevent damage to these areas. This affected the design considerably but we were compelled to work within these parameters," explains Francois.

Another stipulation was the use of labour intensive construction methods which were prescribed for job creation purposes. "Our tender document had to incorporate measures to ensure that labour was optimized. There were however instances where the use of machinery was unavoidable especially in cases where the terrain was difficult to excavate by hand. In order to conform to the labour requirements of the project, local operators were appointed and trained in each village to perform scheme servicing functions like scouring pipelines, checking for air valves and cleaning flow restrictions."

The Ngqusi bulk water supply project is a long way from completion but the many challenges already faced serve only to fuel Francois even further in achieving unparalleled greatness. "I am passionate about water design and the great thing about the Ngqusi project, is that it will be a challenge right through to the end. I am grateful for this because it allows me to test my competence and reach new heights." Francois' confident smile says it all.


 
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