Global South water-sensitive cities: Framing the discourse

Urbanisation is inherently extractive — of both natural and manmade resources. A large concentration of people living together in a city puts unreasonable demands on its natural and built environment as well as on water, energy and food. 

It also generates waste and wastewater in large quantities. A Net Zero-waste city is impossible. You can at best aim to reduce the volume of waste and recycle it.

How cities cope with the increasing demands of their growth has been a centre of discourse and frameworks in the past few decades. 

A discourse is defined by Britannica as “a long talk or piece of writing about a subject”.

The discourse on water-sensitive cities as well as those on sustainable cities, climate resilient cities, water wise cities, liveable cities, river sensitive cities, sponge cities have emerged in the last few decades and have grabbed the attention of organisations and common people alike. These discourses point out the problems and challenges of water, wastewater and stormwater management of urbanisation. 

A framework is defined as “a set of ideas or facts that provide support for something”.

A framework of analysis emerging from a discourse, can be useful for understanding the various facets of a subject or an issue. It may also help in developing an approach to action. But in order to do so, it must define priorities, not try to capture everything in a picture or an infographic alone. A framework must be contextualised in time and space.

Water-sensitive cities — contextualising the discourse 

Water Sensitive Urban Design (WSUD) “is an emerging urban development paradigm aimed to minimise hydrological impacts of urban development on environment”. 

As is evident from this definition, the focus is on reducing hydrological impacts resulting from more and more built landscape. In practice, this means combining groundwater recharge and not simple drainage of stormwater as one outcome, besides several accompanying measures that reduce run off and increase infiltration.

Reducing the risk of flooding is another outcome. Improving the micro-climate of a city, making its public places more pleasant, benefitting its tourism and economic development potential — the benefits that improved water management can bring for a city are plenty.

Therefore, no one will disagree that WSUD is a great idea. After all, the built concrete and paved urban landscape does not allow water to infiltrate, creating huge runoff. 

This should be true in all contexts and for global north and south cities? Yes it is, in a general normative way. However, cities of the Global South may not be able to undertake all that the cities of Global North are able to do to implement WSUD. And here lies the need to frame the discourse, or rather develop a framework for analysis of the water sensitive cities discourse for Global South cities.

Aarhus is the second largest city of Denmark. It is considered a world-class example of a climate resilient city for its water catchment work upstream, followed by a combination of water conservation and harvesting measures (green as well as grey underground concrete tanks) and the paved road over the river downstream, making the riverfront an attractive tourist destination.

The work done is indeed very impressive and appropriate for the city of Aarhus. What is important to note is the scale. The length of the river that flows into the harbour city is only about 10 kilometres from its origin in the hills. It is smaller in length and volume than the waters in the rivers of Indian cities. 

However, it will be unfair to say that this is all that constitutes a water-sensitive urban design initiative in the context of Denmark or elsewhere in European or other developed countries.

A recent study undertaken for a 15 square kilometre area of the Copenhagen WSUD initiative showed that this was a combination of several concepts: Hydrogeology, sewer hydraulics, environmental chemistry / economics / engineering, landscape architecture and urban planning. The study highlights a mix of strategies followed: 

• Stormwater runoff is infiltrated in areas with relatively deep groundwater levels at a ratio that doesn't create a critical rise in the groundwater table to the surface. Delayed and regulated overflows to the sewer system.
• Neighbourhoods located near low-lying streams and public parks are disconnected from the sewer system and the sloping terrain is utilised to convey runoff. 
• Promotion of coherent blue and green wedges in the city is linked with WSUD retrofits and urban climate-proofing. 

Understanding the application of WSUD in the Global North countries requires an appreciation of their urbanisation, climate and rainfall patterns, water and energy use — all that allows them to undertake a particular typology of WSUD interventions. 

Aarhus town has less than a million population. It’s a modern planned city that allows for water conservation and recharge to be implemented rationally across the city. It is a welfare state that ensures access to basic services, including health, education, water and sanitation, as rights of all citizens.

Urban planning norms define and enforce a settlement density, housing and transport, as well as a planned network of water supply and waste water treatment systems covering the entire city. 

There are no slums and informal settlements living precariously without access to sewerage or stormwater drainage. Wastewater treatment systems are functional, serve everyone and are monitored for performance. 

Groundwater recharge is also monitored. Quality of groundwater is so good that countries like Denmark don't need to chlorinate their drinking water supply (entirely sourced from groundwater). 

Rainfall intensity is not restricted to monsoons — rainfall is evenly spread throughout the year and usually below 1,000 millimetres. The cold temperate climate does not harbour mosquito breeding in stagnant waters. 

Pavements and roads are not occupied by cars and can be used as recharge grounds. Manufacturing and polluting industries are completely banished; strict rules are applied to even car washing and spillage of oil. 

In this context, WSUD can be easily applied as an “emerging urban development paradigm aimed to minimise hydrological impacts of urban development on environment”. 

Here the urban development premise incorporates water-sensitive thinking. WSUD is not a ‘project’ or a set of interventions that is imposed irrespective of urban development planning. 

A range of interventions can then be applied, one complimenting the other. Parks and open spaces can be used for groundwater recharge. Recharged groundwater is pollution-free and directly used for drinking water supply. 

Flooding risk mitigation measures (of relatively small size underground concrete water tanks) can handle the intermittent rainfall of European cities unlike monsoon spells in south Asia. 

A water-sensitive cities framework is needed for Global South cities under an urban planning and development approach that is badly missing for India and our cities, as we stare into an emerging water and waste management crisis. 

So far, we have been applying the discourse developed elsewhere, without identifying some core principles, a “set of facts and ideas” that are material to the context of cities of the Global South. To “provide support for specific engagement / interventions” that should be prioritised for our cities. 

Simply copy-pasting the concepts and trying to apply them to Indian cities will run the risk of achieving sub-optimal solutions for water, wastewater and stormwater management.