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What-If

Explore what could change.

Choose a place, a documented issue and one of its documented interventions, then set how far it goes.

ILLUSTRATIVE SCENARIO — NOT A SCIENTIFIC PREDICTION. Built from documented causes, impacts and solutions plus general qualitative patterns. It contains no modelled numbers.

3 · Intervention
PilotScaledTransformative

Adopted across much of the area, with dedicated budgets and enforcement.

Illustrative scenario

What if Bengaluru took a scaled approach to “Lake rejuvenation”?

Starting point · documented

WaterSeverity: High
Lake loss and water stress in Bengaluru

A city far from major rivers depends on distant pumped water and depleted groundwater, while many of its historic lakes have been lost or polluted.

The intervention · documented

Lake rejuvenation

Desilting, sewage diversion, restored inlets and outlets and community stewardship of lakes.

Can restore storage, recharge and ecological function where sustained.

Schematic direction of change

Supply and demand measures can act within years, while groundwater, rivers and wetlands often take much longer to recover.

Schematic, unitless illustration: relative pressure over time without the intervention compared with the intervention in place. Not based on measured data.NowLonger term →Relative pressure (unitless)
Without the intervention With the interventionSchematic shape only — no data, units or dates.

Causes this could address

  • Encroachment on lakes and their channelsBuilding on lake beds and stormwater channels breaks the cascade that once connected the lakes.
  • Untreated sewageWastewater entering lakes causes eutrophication, foaming and odour.

Impacts that could ease

  • Water shortages and costsHouseholds dependent on tankers face higher costs and unreliable supply during dry periods.
  • Urban floodingLoss of lakes and blocked channels reduces the city's capacity to absorb heavy rainfall.

Wider reach at higher intensity is an assumption of this illustration.

How change might unfold

  1. Near term

    Operational gains such as reduced losses or new storage begin to show.

  2. Medium term

    Supply becomes more reliable in ordinary years if measures are sustained.

  3. Long term

    Aquifers and ecosystems recover slowly, if extraction and pollution stay below recharge and assimilation.

Faded stages are less likely to be reached at scaled intensity.

What this would not change

Rainfall variability and drought remain; interventions change how well the system copes, not the weather.

What it depends on

  • Sustained funding and institutional capacity
  • Consistent enforcement and monitoring
  • Local stakeholder support
  • Participation of affected communities

ILLUSTRATIVE SCENARIO — NOT A SCIENTIFIC PREDICTION. Built from documented causes, impacts and solutions plus general qualitative patterns. It contains no modelled numbers.

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