India's Reservoirs Are at 67 Per Cent. The South Is at 42 — and Rabi Now Rests on a Second Monsoon

A national storage average can hide the only number that matters. India's 178 major reservoirs held 123.228 BCM this week, 67 per cent of their 184.762 BCM live capacity, on the Central Water Commission's weekly status reported on 22 October. That is 26.5 percentage points below a year ago and 18.5 percentage points below the ten-year normal. Storage also fell on the week, from 126.72 BCM a week earlier. For a lender or insurer reading one headline number, 67 per cent sounds tight but manageable. It is not one position. It is at least two, and they point in opposite directions.

The split inside the average

Only the central region sits above 80 per cent of capacity. The south sits at the other end of the table:

Position, week to 22 Oct 2026	Storage (BCM)	Capacity (BCM)	% of capacity	Comparison
All India (178 reservoirs)	123.228	184.762	67%	26.5 points below last year; 18.5 points below 10-year normal
Southern region	23.659	55.879	42%	Lowest of the regions reported
Central region	—	—	Above 80%	Only region above 80%

Source: Central Water Commission weekly reservoir status, as reported by BusinessLine, 22 October 2026. Table: Farmioc.

A week earlier the same CWC series had the south at 44.3 per cent, against 89.7 per cent a year ago and a normal of 77.5 per cent, while the centre held 86.4 per cent. So this is not a one-week dip. The southern deficit against both last year and normal was already wide in mid-October, and it widened again. Rabi planning in the southern commands starts from roughly half the stored water the same commands had last October. That gap, not the national 67, is the exposure.

Tamil Nadu and Andhra Pradesh carry the sharp end

Inside the southern figure, the state detail is worse than the regional average. Dams in Tamil Nadu and Andhra Pradesh were filled to less than one-third of capacity. Tamil Nadu has nine reservoirs in the CWC count: Aliyar dam remains empty, and of the other eight, six hold less than one-fourth of their capacity. Across the country only 11 reservoirs are full, four of them in Jharkhand. A command area served by a reservoir at a quarter of capacity does not get a quarter of a normal rabi season by default; it gets a rationing decision, taken by someone else, on a timetable the borrower does not control. Credit files that assume a full irrigated rabi in those commands are carrying an assumption the water position no longer supports.

The rain that did not arrive, twice

Storage this low in late October is the residue of a weak season, and the season's own numbers explain it. IMD's end-of-season summary puts June–September rainfall at 759.4 mm, 87 per cent of the LPA of 868.6 mm — the fourth-lowest season since 2001. The South Peninsula took the heavier hit at 76 per cent of LPA, 542.0 mm, while Central India finished near normal at 97 per cent. Measured over the monsoon's full active window to withdrawal, IMD data put all-India rainfall 15 per cent below its long-period average. The regional storage table and the regional rainfall table are the same table, read three weeks apart.

October has not repaired any of it yet. Post-monsoon rain from 1 to 21 October was deficient in 75 per cent of 734 districts, on IMD figures cited in the same report. Soil moisture going into rabi sowing is therefore thin even where reservoirs are not the binding constraint, and rainfed rabi acreage in the south and centre-east starts the season with less stored moisture than the sowing calendar assumes.

The refill now depends on the northeast monsoon

The southwest monsoon withdrew from the entire country on 15 October, and the northeast monsoon set in over the south the same day — Tamil Nadu, Puducherry and Karaikal, coastal Andhra Pradesh, Rayalaseema, south interior Karnataka, and Kerala and Mahe. For Tamil Nadu in particular, this second monsoon is not a supplement; it is a primary water source, and it is now the only route by which southern storage recovers before rabi demand peaks. IMD has forecast rain over Tamil Nadu, Puducherry, coastal Andhra and Kerala until early next week — a forecast, dated 22 October, not a refill. Whether it converts into reservoir inflows, rather than coastal runoff, is the variable to watch over the next four to six weeks.

What risk teams should do with a 42 per cent south

Split the portfolio view by command, not by state average. A southern book that mixes Cauvery-delta exposure with better-filled Karnataka commands will misprice both. Reservoir-wise storage, updated weekly from the CWC series, is the granularity the decision needs.

Re-test rabi crop-loan assumptions in Tamil Nadu and Andhra commands now. Where the serving reservoir is below one-fourth of capacity, expected irrigated acreage, crop choice and yield assumptions in the file need a second look before disbursement peaks, not after the first water release is curtailed.

Flag the insurance asymmetry. Kharif claims are still being assessed off a deficient season, while rabi sum insured in the southern commands is being written against a water position that depends on a monsoon that has only just set in. Underwriters should treat northeast-monsoon performance over the next six weeks as a live rating input for southern rabi, not as background weather news.

Leave the centre and west on a different setting. Storage above 80 per cent in the central region supports a normal monitoring cadence there. Applying one national watch level to both positions wastes attention on the comfortable book and under-watches the exposed one.

This is the layer Farmioc DataStore works at: reservoir, rainfall and crop signals joined at district level, so a credit or insurance team can see a southern command deteriorating in October rather than discovering it in a February claim or a March overdue account. The water position for this rabi is already set in the centre. In the south, it is still being decided — by a second monsoon, in the next six weeks, in full view of anyone watching the weekly numbers.

Farmioc is India's agriculture data analytics and agri trading company. Explore DataStore for supply, demand, weather and yield analytics, or PriceHub for commodity market intelligence across 200+ crops.