Chennai - TN

Days of Water Left

Updated 7 Aug 2026
246 days+
days remaining
Worst case (no rain):246 days
Current trend:Won’t run out(inflow 2.9x of demand)
If seasonal rains:Won’t run out(inflow 4.2x of demand)
Reservoir storage: 5,563 / 13,222 mcft42.1%
Around this day in 2019: 112 mcft(better today)

Chennai's water at a glance

Reservoir storage is under half capacity. Reservoirs hold 42% of capacity. 14 of 194 groundwater wards show stressed or critical levels. 65 wards are declining year-over-year. 246 water bodies near degraded rivers are flagged for priority restoration.

Explore groundwaterSee restoration prioritiesFlood risk and drainage

Reservoirs: 2026-08-07 | Groundwater: Mar 2024

Catchment Rainfall Context

4 of 4 supply reservoir catchments are below normal over 30 days. Red Hills (Puzhal) catchment is 43% below its 30-day norm.

Chembarambakkam
Below-39%
Red Hills (Puzhal)
Below-43%
Poondi
Below-37%
Cholavaram
Below-43%

Catchment rainfall through 30 Jun 2026 (30-day window). Catchment boundaries are provisional, pending verification.

Reservoir Status

Chembarambakkam

56.4%
2,054mcft
of 3,645 mcft capacity
In: 0Out: 204

Red Hills (Puzhal)

51.9%
1,713mcft
of 3,300 mcft capacity
In: 245Out: 207

Poondi

33.6%
1,086mcft
of 3,231 mcft capacity
In: 440Out: 286

Veeranam

24.0%
351mcft
of 1,465 mcft capacity
In: 0Out: 73

Kannankottai

52.2%
261mcft
of 500 mcft capacity
In: 0Out: 19

Cholavaram

9.1%
98mcft
of 1,081 mcft capacity
In: 30Out: 8

Groundwater Health

Explore map
Data may be outdated. Latest available from OpenCity / CMWSSB is Mar 2024. We're actively looking for newer sources.
5.0m
city average depth to water table
Healthiest: Ward 6 (0.5m)
Most stressed: Ward 32 (16.0m)
Ward distribution (194 wards)
52 healthy88 moderate12 stressed2 critical

Chennai basin water balance

Explore sub-basin risk→
Total water demand
2,479 → 2,728 MCM
2025 → 2050
Unmet demand (business-as-usual)
546 → 654 MCM
by 2050

Treated-water reuse + micro-irrigation can cut unmet demand 52-93% by 2050.

Risk index & scores: TNGCC and CEEW 2026, "Towards Climate-resilient River Systems in Chennai" (CC BY-NC 4.0).

Search latest Chennai water news→|Via Google News

Groundwater

CGWB block exploitation, ward depth (interpolated), live WRIS station overlay.

Water bodies

OSM polygons, flagship tanks, restoration priority badges, lost-tank inventory.

About this dashboard

Methodology, data sources, water sources tracked, and the data gaps we're honest about.

Methodology: Reservoir levels for Chennai from CMWSSB. Daily consumption assumptions (~830 MLD demand) are starting points; the sliders above let you substitute your own. See theAbout pagefor the full data-source index and methodology.