“if there had been no drought or impact from climate change, it would have occurred by 2019”
The water crisis in Cape Town has raised some serious questions about the future of the city. In this interview with Rebecca Cameron of MCA Urban and Environmental Planners, we look at how Cape Town could transition towards a more water secure future.
Water is essential to life. Current urban water systems often degrade freshwater ecosystems, nature’s ability to replenish resources and the relationship between people and the environment. To address this, integrated urban water management (IUWM) has been developed; yet, is too often undermined by institutional paralysis and a subsequent lack of physical change in cities. This paper presents key learnings from research undertaken to understand how spatial planning can be utilized as a tool in IUWM; where hydrological systems influence the form and structure of cities. The intention is to improve water literacy in urban planning where complex conditions confront urban and natural systems.
Abstract from from Cameron, R and Katzschner, T. 2016. The role of spatial planning in enhancing Integrated Urban Water Management in the City of Cape Town. South African Geographical Journal. 99(2), pp. 196 – 216.
Why has it taken so long and an extreme situation like this to start responding to water insecurity in the Western Cape?
From the research I have undertaken it is evident to me that the City of Cape Town and the Western Cape Government have long been aware of an impending water crisis in Cape Town and the province. If there had been no drought or impact from climate change, it would have occurred by 2019.
It has occurred two years earlier than anticipated. We didn’t reach this crisis earlier is due to the successful implementation of Water Demand Management Strategies in the City of Cape Town (Download here). The structure and pricing of our water system is based on the assumption that there will be a constant supply of available and easily accessible freshwater. This assumption no longer holds true, so our water system must be restructured to reflect a more flexible.
What does the diagram tell us about the water use mix and demand in Cape Town?
This is a Sankey Diagram that is used in Material Flow Analysis, often a method applied to industrial systems. The water system is currently viewed and operated in a series of parts rather than holistically.
This diagram is helpful in that it places all aspects of the water system in to one diagram. Here, water supply, water use, wastewater treatment and stormwater have been considered as a single system where too often the urban water cycle is fragmented when addressed within different sectors. The arrows of flow follow a key to represent the quantity and quality of water. The size of the arrow of flow is proportionally indicative of the quantity of water that flows from one process to one another. The colour of the arrows indicates the quality of the water flow; this includes non-potable, potable, sewage, treated sewage, and treated sewage for reuse. This is important to represent as, to intervene in an urban water cycle, both quantity and quality of water must be considered and used appropriately to move towards a more efficient and sustainable water system.
The City of Cape Town is located in the Berg River Catchment which forms part of the Western Cape Water Supply System. The City of Cape Town is the largest water user in this system, but we also share this system with Stellenbosch, Paarl, Saldanha Bay, and all the farmers surrounding these towns, to name a few.
This means that an unconstrained increase in demand for water from the City of Cape Town would negatively affect the availability of water for surrounding towns and agriculture, which could result in a vicious cycle of food insecurity and economic instability in the region. The water for this system is sourced from a range of rivers with dams, predominantly outside of the municipal boundary, and a few ground water sources. The primary water users are those living in formal residential areas, who also contribute the greatest sewerage load to the wastewater system.
Overall, this diagram indicates a picture of linear water flow where outsourced water supply is relied upon as the primary water source; potable water is used for all purposes whether necessary or not; and very little water is reused. This system is operated at great cost to the environment and the municipality
What is the potential for expanding the water supply in Cape Town and transitioning towards a more water secure future?
As I learnt through this research, both socio-political and technological transition is required.
With water as a vital yet highly threatened and limited life-support in our cities, it is necessary to move towards more sustainable and resilient patterns of interaction, as nature has evolved to do. One way, is to envision the City as a Catchment. Where space is made for water to be celebrated, to absorb stormwater to use it in the surrounding areas, and to develop local recycling systems in every community. With these systems in place, the city would be more resilient due to smaller, more flexible systems and we could have more water than we need.
Following from this, I have put forward four metropolitan-wide strategies:
- Firstly, that freshwater systems and their associated ecological corridors are identified as spatial structuring devices in the city to promote improved functioning and increased urban prominence.
- Secondly, District Water Systems are spatially aligned to socio-ecological informants and act as municipal governance structures to enable the integration of area-based interventions.
- Thirdly, with the creation of ‘Urban Water Lungs’, public open spaces are connected within each district to form water harvesting and reuse systems to promote local subsistence.
- Fourthly, urban activity routes and the hydrological network carry the flows of people and water respectively. Where these intersect, there is a confluence of energy creating the opportunity for a community node or hub. These are referred to as ‘Urban Bridges’ and they offer the chance to reconnect socially and ecologically; as is partially in place where the Liesbeek River intersects with the Durban Road corridor.
How do these strategies fit together?
There are a variety of appropriate strategies that can be implemented at the building, neighbourhood, district and metropolitan scale in accordance with spatial and system thresholds such as capacity, influence and level of supervision. These strategies exist in a spatial hierarchy of networked systems. It is important to see these strategies working simultaneously and in conjunction with one another as no single strategy is able to address the complexity of transitioning to increased water-security in Cape Town.
Here are some questions to start conversations and, hopefully, change; with key questions being:
- How can freshwater systems become spatial structuring devices in urban areas?
- How does our language and attitude shape our interaction and relationship with natural systems?
- What intervention in urban water management is needed at the metropolitan scale?
- Who needs to collaborate to enable this transition to a water-secure city?
- What are the socio-political and economic implications if we are to rely on locally-sourced, cyclical urban water systems?
How can we re-imagine the city and its design moving forward?
This research has offered the chance to re-imagine the city; one which acknowledges the significance of freshwater ecologies not only in how we manage urban water systems but, also, in how Cape Town is shaped. Therein lies the opportunity to not only promote local subsistence and a cyclical use of resources but also to reconcile the human-nature relationship.
Rebecca Cameron works for MCA Urban and Environmental Planners
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Aerial image of the Berg River Dam between Franschhoek and Paarl, South Africa.