2.1.4 Principles of the Sponge Approach

SPONGE COLLABORATIVE + WEAVING WITH WATER Team

MULLASSERY CANAL FRAMEWORK AND CANAL EDGE MASTERPLAN

Figure 23: Sponge Framework opens up the potential of budgets allocated to stormwater management and drainage towards the creation of blue-green infrastructure that are resilient to cloudbursts and improve public life (Image Credit: Sponge Collaborative)

2.1.4 Principles of the Sponge Approach:

The Sponge Framework principles present a strategic framework for developing the Mullassery Canal precinct as a vibrant, safe, and resilient neighborhood. Highlighting strategic infrastructural moves and how they function across various storm scenarios. Further, the document identifies specific pilot projects that can be quickly implemented within the next year or so to kickstart an ambitious but rewarding strategy to make Kochi a climate-smart city.

Figure 24 - The Landscape Principles as part of the Sponge Framework highlights Nature Based Solutions (NBS) to make the city climate-resilient (Image Credit: Sponge Collaborative)

SPONGE COLLABORATIVE + WEAVING WITH WATER Team

MULLASSERY CANAL FRAMEWORK AND CANAL EDGE MASTERPLAN

1.Protect existing green systems, surface water systems, and groundwater aquifers: 1) through community mapping of trees, urban forests and groves 2) Putting in place mechanisms to monitor the ecological health of existing water bodies and lakes 3) Community-led aquifer mapping zones and designation of aquifer recharge zones with a set of strategies to protect these designated zones

2.Restore polluted blue-green and groundwater systems through: 1) sustainable soil management and rehabilitation of degraded forests and polluted soils 2)Renaturalisation of waterbody edges, including canals and lakes 3) Recharging polluted and depleted aquifers

3.Enhance the resilience of existing landscape assets such as park systems, coastlines and aquifers to deal with extreme weather events: 1) Reimagining open spaces such as community groves, parks, maidans, and even parking lots or bus depots as key pieces of stormwater management infrastructure 2) Protecting coastal edges against erosion 3) Protecting saltwater intrusion in coastal aquifers

4.Construct new blue-green infrastructure 1) Increasing natural ground cover on multiple surfaces to reduce the runoff coecient through policies that encourage the creation of green roofs and constructed wetlands 2) Creation of decentralised water retention and channels by means of bioswales, curb bulb outs, rain gardens and pervious pavement on existing streets and open spaces 3) Construction of new water bodies, and pits for groundwater recharge.

Figure 25 - Global best practices showcasing Nature Based Solutions (NBS) (Image Credit: Sponge Collaborative)

The framework highlights the potential of a blue-green infrastructure network by upgrading streets and open spaces in order to supplement grey stormwater capacity and improve the resilience of the canal. Recognising the limitations of traditional grey infrastructure to effectively handle extreme weather events, Nature Based Solutions (NBS) are proposed for water management in this precinct.As the groundwater is highly saturated, and with