5.0 The Case for Change

5. The Case for Change

5.1 In-Existence Approach

Do The City Require Grey Infrastructure?

Figure 10 : Kharicut canal existing proposal Source : Times of India

The 138 years old Kharicut canal will be covered and converted into a 21-kilometer six-lane road. The state officials have given AMC in-principle approval for the redevelopment of the water channel at a worth of Rs 451crore. The proposal will curb the pollution caused by toxic waste, illegal dumping of domestic waste and also ease traffic congestion in the surrounding industrial areas. The new envisaged avatar of the urban water channel will quietly replace earlier plans for a vehiclefree, pedestrian-friendly public space along the course of the canal. The canal likely to turn into a closed duct carrying sewage and stormwater lines to reduce waterlogging led to a question does the city require a grey infrastructure solution? Because on the other hand, countries across the globe are adopting nature-based solutions to peel their grey infrastructure to a natural flowing water stream.

Case Study | Nature Based Solutions: A Key to Resilient Infrastructure

Before

Cheonggyecheon Stream, Seoul

After

11 Master of Urban Infrastructure 2019-21

Before

Bishan-Ang Mo Kio Park, Singapore

After

Revivifying Course: Envisioning The City Through An Urban Water Channel

5.2 Future Proofing: The Change in Perspective

The delineated issues led the urban water channel to accumulate solid waste, hazardous industrial effluent/ sewage, deterioration of water quality, and highly mismanagement of stormwater, which has become an eyesore to the residing communities today. A leap forward is needed to shift the common perception of stormwater as a waste to a non-renewable natural resource to be protected and stored. The idea to capture increased urban runoff can be summarized through four nature-based strategies under the theme Make Room for Water.

Making Room for Water

Design for variability: As water processes are seasonal, the design should reflect variability and periodic flood change.

Sponge spaces and safe failure: The network of small-to-medium sized green areas to absorb and store excess runoff water.

Don’t let it go: Rainwater is a precious resource and should be retained and used on the spot.

Let it seep through: Permeable grounds restore the natural water cycle, allowing humidity exchange between air and the soil. [1]

[1] Design for flooding: how cities can make room for water

5.3 Global Concepts and Good Practices

The integration of stormwater solutions with urban development is a way to reintroduce the natural water cycle as nearby. There are a variety of tools and methods which cities across the globe adopt for the innovative integrated stormwater. The concepts of Water Sensitive Urban Design (WSUD), Low Impact Development (LID), Green stormwater infrastructure (GSI), Urban Watershed Management, Sponge City, and Integrated Blue-Green Systems approaches are widely applied to solve stormwater challenges with boosting urban development. Unlike the standardized stormwater drainage system, these practices emphasize stormwater as a resource and as a concern to build liveability and resilience.

Figure 11 : WSUD Water cycle Source : Hoban & Wong,2006

Water and Sanitation Studio 2020 |Stormwater Sector 12