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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 Lagos took a scaled approach to “Drainage clearing and upgrades”?

Starting point · documented

WaterSeverity: High
Flooding and coastal erosion in Lagos

A low-lying lagoon city faces recurrent rainfall flooding, coastal erosion and rising seas.

The intervention · documented

Drainage clearing and upgrades

Regular clearing of drains and canals ahead of the rainy season.

Reduces local flooding.

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

  • Heavy rainfallIntense tropical downpours overwhelm drainage.
  • Blocked drainsSolid waste reduces drainage capacity.

Impacts that could ease

  • Damage to homes and roadsFlooding damages property and paralyses traffic.
  • Health risksFloodwater spreads waterborne disease.

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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