Madurai · Flood riskVaigai system scopeNo known public hazard map - external monitoring only

Madurai flood risk

Madurai's flood risk is dam-release-driven, not rainfall-driven. The Vaigai's natural catchment is small (2,253 sq km); urban inundation tracks Vaigai-dam outflows on a 12-24 hour lag. There is no public CFM-DSS-equivalent sensor mesh - upstream context comes from CWC and the dam-level scrape.

Dam-release threshold for downtown inundation
~6,000cusecs

~6,000 cusec releases from Vaigai dam saturate the downtown channel between Albert Victor bridge and Anuppanadi. Below this threshold the Vaigai bed absorbs the flow; above it, low-lying wards (Sellur, Avaniyapuram, Anuppanadi) start flooding.

Recent flood events · 2

20236,000 cusec release from Vaigai dam during NE monsoon

Downtown Madurai inundated; Avaniyapuram and Sellur worst-hit; release coincided with peak rainfall in the catchment.

2018Sustained NE monsoon + Periyar tunnel diversions

Significant Vaigai-bed inundation; upstream-tank cascade overflow into peri-urban kanmoi.

ScienceDirect (Vaigai flood-frequency analysis)

What we don't have (Madurai)

  • No CFM-DSS-equivalent sensor mesh (Chennai has ARG/AWS/AWLR/gate sensor network; Madurai does not)
  • No public flood hazard zone GeoJSON (5/10/25/50/100/200-year return period polygons)
  • No public 2018/2023 hotspot inventory (RTI-needed from MMC)
  • Flood inundation depth raster - not modeled publicly for Madurai

Chennai's flood-risk page renders modeled hazard zones, 2015/2020 hotspots, drainage and sewerage overlays - none of which exist publicly for this city. This page surfaces what's actually available rather than papering over the gap with synthetic data.