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Project
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Netcare
Private en suite room.
The hospital required a drainage system that drains quickly with little or no chance of blockages.
Client brief The client, Netcare, needed a water and drainage system that was efficient, compact and sterile, explains Reza Davids of Ekcon who handled the wet services design aspect of the project. The hospital required a drainage system that drains quickly with little or no chance of blockages. Water must be of adequate pressure and temperature( hot water), both for equipment and sterile purposes.
“ As it’ s a state-of-the-art hospital, it required many services to be incorporated into a small ceiling area, including HVAC, medical gas, water, drainage, fire protection sprinklers, electrical cables, and a pneumatic tube to transport medication,” explains Davids.“ Finding the space to route our piping was very challenging.” Thus the water system had to be designed in such a way that the water ring main stayed within 3 – 4m of the sanitary fixtures to minimise the length between the sanitary fixtures and the water ring main. This was to reduce the amount of stagnant water in the pipe and subsequently reduce the chance of bacteria being discharged.
System description Davids walked us through the wet services design of the hospital.
Sewer The sewer system consists of vertical sewer stacks running from the roof of the building all the way down to
the basement. There are areas where the stacks had to be re-routed to a different position on one floor to fit in with the architecture and routed back on the next floor, which made things quite challenging considering the amount of space and other services around.
All the stacks are collected on the soffit of the basement via collector pipes, which are then routed into a sewer manhole on the outside of the building. Ekcon, with the help of Modern Plumbing Works Cape as wet services contractor, also installed a backup sewer system that consists of a sewer sump in Basement-2( where the oncology bunker will be located). This system comprises an upsized sewer pump that will kick in when there is a blockage in the council’ s main sewer line in the road. This will pump the sewerage back into the sewer manhole on the outside of the building at a higher pressure, preventing the sewerage from building up and rising up through the sanitary fixtures on ground floor. As the hospital is a clinical area, such a rise up of sewerage would be completely unacceptable.
During construction, there were two cases of the council sewerage system causing blockages and as such, the sewage system was designed in this new manner to prevent this from happening once the hospital became operational.
The subsoil drainage system drains the water from the soil around the foundation of the building. This reticulates all around the pile footings, which then gravitates to two
February 2017 Volume 22 I Number 12 www. plumbingafrica. co. za