The season ahead, in the agencies' own words
This is not a vague warning. In February 2026 the National Disaster Management Centre classified the drought in the Eastern, Western and Northern Cape as a national disaster. In its August 2026 diagnostic discussion the American climate agency NOAA placed a formal El Niño advisory, putting the chance of a very strong El Niño this coming summer above 90% — and the South African Weather Service has said the likelihood of below-average rainfall rises from November onward. Both agencies reissue those outlooks monthly, so check the current one before acting on the figure here. Forecasts are probabilities, not promises; but the last strong El Niño, in 2023-24, cut the maize crop by more than a fifth. The time to build water resilience is the season before it is needed — which is now.
How many days of water is your farm?
The KZN Department of Agriculture's storage rule is the place to start: hold at least 8 days' supply in main storage and at least 2 further days at the drinking points, with a water cart on standby. The arithmetic is short. A hundred beef cows at 50 L/day need 5 000 L a day — call it a 40 000 L main reserve. A 200-cow dairy herd in milk is a different animal: at five litres of drinking water per litre of milk on top of the cow's own maintenance requirement, 25 L/day of milk means roughly 125 L per cow for the milk plus her maintenance drinking — call it 150 L, so about 30 000 L a day, and that is still before parlour washdown, which on most dairies adds a further fifth to a third again. An eight-day reserve is 240 000 L before wash water, and closer to 300 000 L with it. If the number surprises you, that is the point of doing it. Count every use: drinking, dairy washing, spray mixing, the house.
An open dam is a leak you can see from space
Over most of South Africa, evaporation takes more than 1 400 mm a year off any open water surface, rising toward 3 000 mm in the arid north-west. Run that on a one-hectare farm dam at a middling 1 800 mm and the sky takes roughly 18 million litres a year — about ten years of drinking water for that hundred-cow herd, gone without a pipe or a pump. The lesson is not to abandon dams; it is that drought reserves belong in closed tanks, where evaporation is nil, algae get no sunlight, and the chlorine you dose survives. Seepage losses through unlined dam walls add a second, invisible drain.
Metering closes the loop. South Africa's municipal systems do not bill for 47% of the water they put into supply (non-revenue water, the national No Drop report, 2023). That figure is not all leakage: it counts physical losses, metering error, unbilled authorised use and theft together, and physical leakage is the largest part of it rather than the whole — farm pipelines are not immune, and a meter on each line is how a silent leak becomes a repair job instead of a mystery. Abstraction above 2 L/s must be metered and logged anyway.
Rain on the shed roof
Roof water is the one supply the National Water Act gives you outright — storing run-off from a roof is Schedule 1, no licence, no registration. The yield formula is one line: roof area × rainfall × 0.85. A 300 m² shed in a 500 mm district collects about 127 000 L a year. Fit a first-flush diverter (discard roughly the first 0.5–2 L per square metre of roof each rain) so the dust and bird droppings of the dry weeks don't open every tankful. What the water is fit for depends on treatment, not on how clean it looks: coarse filtration is enough for washdown and irrigation, while drinking standard means the full train — filtration, then UV or chlorination — as covered in the backup-water article in the Specialised applications section.
Reuse before new supply
The cheapest new water is water used twice. A dairy's plate cooler pushes two to three litres of clean, slightly warmed water through for every litre of milk — catch it for stock drinking or the first washdown rather than letting it run to ground. Final-rinse water from plant cleaning can open the next wash. And treat tankered water as what it is: a bridge, at roughly forty to fifty times municipal rates, never a plan.
The registrations
Storage above 10 000 m³ must be registered under the general authorisation. The general authorisation is reissued from time to time and its volumes differ by catchment, so confirm the current notice for your quaternary catchment rather than relying on the figures here. A dam holding more than 50 000 m³ with a wall higher than 5 m is legally a "dam with a safety risk" and must be registered with the Department of Water and Sanitation. And note the drought clause farmers forget: even Schedule 1 stock-watering rights can be limited by catchment notice in a declared shortage — the paper trail you keep now is your seat at that table.
Rule of thumb
Hold eight days of water in closed storage and two more at the troughs. Cover what you store; meter what you move; harvest the roofs before you drill. Do the herd's arithmetic honestly — dairy cows drink by the litre of milk — and start this season, not the one the forecast finally gets wrong.