Using treated effluent for a water resilient Century City Urban Square precinct

This case study by GreenCape examines the Century City Urban Square (CCUS), a mixed-use development by Rabie Property Group in Cape Town. The project demonstrates how the integration of treated effluent (TE) for non-potable uses—such as irrigation, cooling towers, and toilet flushing—reduces potable water demand, lowers operating costs, and increases resilience against climate-related shocks like droughts.

• The Century City Urban Square (CCUS) utilizes treated effluent (TE) sourced from the municipal Potsdam treatment works via a dedicated pipeline for irrigation, cooling tower consumption, and toilet and urinal flushing. This strategy has offset potable water consumption by approximately 44,000 kl per annum, resulting in water and sanitation savings of R2.3-million based on 2021 tariffs.
• The use of treated effluent is significantly more cost-effective than potable water. According to 2021 water tariffs, the cost of using treated effluent is R3.42 per kilolitre, compared to R28.39 per kilolitre for potable water, excluding sewer discharge costs.
• A comparison of 2017 data shows that the CCUS is substantially more water-efficient than a similar mixed-use development by Rabie Property Group that lacks resilience measures. The CCUS consumed 0.18kl per annum per Gross Building Area (GBA m2), while the comparable building consumed 1.09kl per annum per GBA, meaning the latter used 270% (2.7 times) more potable water despite being only 43% of the CCUS's gross building area.
• The CCUS was the first mixed-use development to receive a four-star rating from the Green Building Council of South Africa (GBCSA) and serves as a pilot project for the GBCSA's new mixed-use rating tool. Other sustainability features include a district cooling system with heat recovery, extensive metering for real-time monitoring and leak detection, and water-efficient fittings like low-flow shower hoses and tap aerators.

APA

GreenCape (2021). Using treated effluent for a water resilient Century City Urban Square precinct. https://greencape.co.za/wp-content/uploads/2022/10/GreenCape_CoCT-Resilience_Rabie_Group-2021-3.pdf

Chicago

GreenCape. Using treated effluent for a water resilient Century City Urban Square precinct. 2021. https://greencape.co.za/wp-content/uploads/2022/10/GreenCape_CoCT-Resilience_Rabie_Group-2021-3.pdf.

Wikipedia

{{cite report |author=GreenCape |title=Using treated effluent for a water resilient Century City Urban Square precinct |date=2021 |url=https://greencape.co.za/wp-content/uploads/2022/10/GreenCape_CoCT-Resilience_Rabie_Group-2021-3.pdf |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{greencape2021using, author = {{GreenCape}}, title = {{Using treated effluent for a water resilient Century City Urban Square precinct}}, institution = {GreenCape}, year = {2021}, url = {https://greencape.co.za/wp-content/uploads/2022/10/GreenCape_CoCT-Resilience_Rabie_Group-2021-3.pdf}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }