Chennai - TN

Days of Water Left

Updated 10 Jul 2026
265 days+
days remaining
Worst case (no rain):265 days
Current trend:Won’t run out(inflow 3.6x of demand)
If seasonal rains:Won’t run out(inflow 3.4x of demand)
Reservoir storage: 5,994 / 13,222 mcft45.3%
Around this day in 2019: 377 mcft(better today)

Chennai's water at a glance

Reservoir storage is under half capacity. Reservoirs hold 45% 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.

Reservoirs: 2026-07-10 | Groundwater: Mar 2024

Catchment Rainfall Context

3 of 4 supply reservoir catchments are above normal over 30 days. Cholavaram catchment is 26% above its 30-day norm.

Chembarambakkam
Above+24%
Red Hills (Puzhal)
Above+26%
Poondi
Near normal+1%
Cholavaram
Above+26%

Catchment rainfall through 31 May 2026 (30-day window).

Reservoir Status

Chembarambakkam

69.4%
2,528mcft
of 3,645 mcft capacity
In: 160Out: 219

Red Hills (Puzhal)

51.1%
1,685mcft
of 3,300 mcft capacity
In: 210Out: 209

Poondi

31.1%
1,006mcft
of 3,231 mcft capacity
In: 210Out: 305

Veeranam

25.6%
376mcft
of 1,465 mcft capacity
In: 965Out: 73

Kannankottai

61.8%
309mcft
of 500 mcft capacity
In: 20Out: 22

Cholavaram

8.3%
90mcft
of 1,081 mcft capacity
In: 0Out: 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Data may be outdated.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).

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.