The urban water metabolism of Cape Town : towards becoming a water sensitive city
Date
2021-05-28
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
ASSAf
Abstract
To improve its resilience to increasing climatic uncertainty, the City of Cape Town (the City) aims to
become a water sensitive city by 2040. To undertake this challenge, a means to measure progress is
needed that quantifies the urban water systems at a scale that enables a whole-of-system approach
to water management. Using an urban water metabolism framework, we (1) provide a first city-scale
quantification of the urban water cycle integrating its natural and anthropogenic flows, and (2) assess
alternative water sources (indicated in the New Water Programme) and whether they support the City
towards becoming water sensitive. We employ a spatially explicit method with particular consideration to
apply this analysis to other African or Global South cities. At the time of study, centralised potable water
demand by the City amounted to 325 gigalitres per annum, 99% of which was supplied externally from
surface storage, and the remaining ~1% internally from groundwater storage (Atlantis aquifer). Within
the City’s boundary, runoff, wastewater effluent and groundwater represent significant internal resources
which could, in theory, improve supply efficiency and internalisation as well as hydrological performance.
For the practical use of alternative resources throughout the urban landscape, spatially explicit insight is
required regarding the seasonality of runoff, local groundwater storage capacity and the quality of water
as it is conveyed through the complex urban landscape. We suggest further research to develop metrics
of urban water resilience and equity, both of which are important in a Global South context.
Description
CITATION: Atkins, F., Flugel, T. & Hugman, R. 2021. The urban water metabolism of Cape Town : towards becoming a water sensitive city. South African Journal of Science, 117(5/6):8630, doi:10.17159/sajs.2021/8630.
The original publication is available at https://sajs.co.za
The original publication is available at https://sajs.co.za
Keywords
City planning -- South Africa -- Cape Town -- Environmental aspects, Sustainable urban development -- South Africa -- Cape Town, Water use -- South Africa -- Cape Town, Water demand management -- South Africa -- Cape Town, Water conservation -- South Africa -- Cape Town, Urban ecology (Biology) -- South Africa -- Cape Town, Climatology -- South Africa -- Cape Town, Municipal water supply -- South Africa -- Cape Town, Urban ecology (Sociology) -- South Africa -- Cape Town
Citation
Atkins, F., Flugel, T. & Hugman, R. 2021. The urban water metabolism of Cape Town : towards becoming a water sensitive city. South African Journal of Science, 117(5/6):8630, doi:10.17159/sajs.2021/8630.