Strategic in-stream systems: A Decentralised anticipatory approach to wastewater contamination in Bangalore

Bengaluru is in the midst of a serious urban water crisis. The surface water flows to the city through a complex system of lakes and open channels (often referred to as the “Tank Cascade System”). Due to unregulated urban development in the past two decades lakes and the open channels receives untreated domestic and industrial effluents.  This untreated effluents hyper-accumulates as it makes its way through this interconnected system, causing a range of impacts to local ecosystems, livelihoods, and public health.

STRAINS “Strategic In-stream Systems”— decentralized, frugal, flexible is a small-scale, low-tech, in-stream approach to wastewater contamination in Bangalore. We have deployed a small scale intervention a “model Nallah”, approximately 2M Wide and 8M long. Within this space, we will run a series of experiments with a variety of materials and treatments.

STRAINS consists of three basic stages aimed at 1) diverting and collecting solid waste, 2) slowing and settling sediment and suspended solids, and 3) lowering BOD, and trace metals levels through biofiltration using locally available aggregate materials.

The ultimate aim is to use the insights of the Sowl Kere studies to develop a series of larger interventions which can be placed directly within nallahs to prevent the contamination and eutrophication of urban lakes.

The overall goal is to

• Optimize the design of STRAINS for efficient removal of contaminants.
• Develop an approach to enhance community participation. We plan to hand over the maintenance of systems to the communities. This will help in promoting community engagement that will lead to a greater impact.

This project is a six-fold partnership receiving inputs from Biome Trust, (project management, collaboration, coordination) MAPSAS (community engagement) Eco Paradigm (engineering & construction), Common studio (design), Wipro (fiscal sponsorship) and ATREE.  ATREE through this project is involved in water quality monitoring of the STRAINS system.

Collaborators:

Biomes Trust - Daniel Phillips