Plumbing Africa September 2017 | Page 31

project The problem After the heavy storms and subsequent flooding in the Meadowdale, Johannesburg area last year, the client at Clandale Projects called in Burgess and Partners Plumbing Services to come up with a solution to prevent future water issues. With the heavy rains last year, the infrastructure in the area was unable to cope with the excess rainwater from the continuous rainfall at the time. The Clandale property has stormwater facilities, as well as stormwater pumps that pump the rainwater into the municipal stormwater drains; however, the infrastructure in the area cannot cope with that amount of water. They needed an alternative solution. 29 The solution Warren Burger, business development manager at Burgess and Partners, got involved and suggested that a rainwater harvesting system take care of the excess water (which could then be used at the client’s will) and also provide a backup to the municipal water supply feeding the toilets. The rainwater harvesting system would feed the 6 500m 2 property’s irrigation system alongside the toilets, drastically reducing Clandale’s municipal water usage. The client was happy with this solution and Burger got to work designing the system. He was also responsible for managing the installation with the help of two of Burgess’ trusted plumbers, Roland Palm and Sam Ngoepe, who completed the job in record time. The system collects rainwater from a portion of the property’s roof and discharges into the five 5 000ℓ Rain Cell rainwater storage tanks. Depending on the client’s preference, the rainwater can then be used at will. By opening and closing two different valves, the system will automatically switch over from the municipal supply, after which the pump will engage and ultimately feed the building with pressurised backup rainwater. The client can now let the water run out into the municipal stormwater drain at their own pace, allowing it to drain properly without flooding the entire system. Tackling the project Burger did a lot of research before sitting down to do the design. Preparations for the project involved working out the total roof space and calculating the rainfall quantities over the past 20 years. He also had to calculate the best place to install the tanks. It was important to ensure that the tanks did not obstruct any windows and that they were not too close to any air conditioners. With regard to the pumps, it was vital to keep them isolated and away from gas bottles and other electronics, according to industry standards and requirements. Burger went to site to establish the number of people on the property, together with the number of taps and toilets the system would be feeding. It was also important to find out what type of toilets were on site (flush master operated toilets or normal low level flushing toilets). The system The first phase of the project involved installing new 110mm PVC downpipes and five 5 000ℓ rainwater tanks Rainwater is collected from the two sides and front of the building. www.plumbingafrica.co.za September 2017 Volume 23 I Number 7