Our Cape Town office recently implemented a rainwater harvesting system, in an attempt to reduce its reliance on the overburdened municipal water system.
The company has adopted various sustainable practices and technologies over the past few years. These include implementing waste recycling, procuring environmentally-friendly cleaning products nationally, training staff on ‘greening’, renovating the Johannesburg and Cape Town production facilities to increase the use of natural lighting, and powering the Johannesburg office with solar panels.
Tashreeq Benjamin, a Quantity Surveyor in our Cape Town branch, took on the task of finding an effective long-term water solution for the Cape Town office. He explains, “We opted for rainwater harvesting instead of pumping water from a borehole for two reasons: Firstly, we have a huge roof area, so we have a catchment advantage. Secondly, pumping requires energy to pull water from the ground, filter it, and then an additional booster pump is needed to send the water to its various outlets for usage. This means three pumps are needed in total. So, going for rainwater harvesting is both greener and more cost-effective than the alternative.”
Two 5 000 litre tanks are now set up to collect run-off from a 780m² section of the warehouse roof. After one tank is full, a switch is triggered to fill the second tank. The tanks connect to the building in such a way that the water is available by simply turning on a tap. The smallest possible pump is used to power the water flow throughout the building, to ensure minimal energy consumption.
A single day with 15ml of rainfall will fill both tanks. This supplies us with enough water to use for our production requirements, cleaning and ablutions for a two-week period.
The long-term goal is to become self-sufficient for all water requirements. To do this, we will install more tanks to capture water from the total roof area, which is an additional footprint of 1 560m² – double what is currently being used.