Load-Shedding and Water Pressure: Why Your Taps Go Dry

Most Johannesburg homeowners have noticed it: load-shedding starts, and some time later the taps either slow to a trickle or stop altogether. The two events feel unconnected — water and electricity are different services — but the link is direct and worth understanding before you decide what, if anything, to do about it.

Why Electricity and Water Pressure Are Joined at the Hip

Johannesburg’s water supply is not gravity-fed from a single high reservoir. It relies on a network of electrically driven pump stations at various points in the distribution system. When those stations lose power, they stop pushing water forward. Pressure in the pipes serving your street drops gradually as the water ahead of the pump drains away downstream. Depending on how far you are from the affected station and how many other households are drawing water at the same time, you may feel the effect within minutes or only after an hour or two.

Johannesburg Water’s own figures show the city’s reservoir system holds roughly 27 hours of citywide storage buffer under normal demand. That sounds reassuring until you consider two things: it is a citywide average, not a guarantee for your specific zone; and demand is rarely ‘normal’ during load-shedding, when residents rush to fill containers and top up geysers the moment power returns, spiking local draw exactly when recovery is still fragile.

The 44.8% Problem Making It Worse

Johannesburg Water’s 2024/25 audited figures put non-revenue water — water produced but lost before it reaches a paying customer, mainly through pipe leaks — at 44.8%. That is not a rounding error; it means roughly one in every two litres pumped out of the treatment works never arrives at a tap. Ageing infrastructure that leaks heavily is also infrastructure that loses pressure quickly when pumps go offline. The two problems compound each other.

What Actually Happens to Your Taps

The sequence typically runs like this:

1. Load-shedding begins; one or more pump stations in your supply chain lose power.
2. Residual pressure in the pipes bleeds off as water continues to flow downstream.
3. Higher-elevation properties and end-of-line addresses feel the drop first and most severely.
4. Power returns; pumps restart, but refilling the network takes time — often longer than the outage itself.
5. Demand spikes as every household simultaneously tries to recover, slowing restoration further.

If you live on a hill or at the far end of a long residential street, you are likely in the worst-affected category at every stage.

What a Backup System Actually Does

A backup water system does not fix the municipal network — nothing you install on your property does that. What it does is decouple your household’s immediate water needs from whatever is happening outside your boundary wall.

The principle is simple: store water when municipal supply is good, draw from that store when it is not. A tank-and-pump arrangement tops up a dedicated storage tank during normal supply, then a pressure pump draws from the tank to maintain pressure inside your home when municipal flow drops. You carry on washing dishes and flushing toilets; the pump station outage becomes your neighbour’s problem, not yours.

For a sense of scale on costs: backup tank-and-pump systems typically run R20,000–R40,000 for a standard installation, with whole-house setups reaching around R55,000. Those figures can shift significantly depending on tank size, pump specification, and your property’s layout, so treat them as a rough guide and confirm via quotes from installers who have seen your site.

If you are weighing up storage options more broadly — including how load-shedding interacts with tank sizing decisions — the post on water storage and load-shedding covers the trade-offs in practical detail.

If you want to know what a correctly sized backup system would cost for your specific home, it is worth getting several installers to assess the property. Compare 3 free quotes — vetted installers, no obligation.

Sizing: How Much Storage Is Enough?

South Africans use on average about 237 litres of water per person per day, according to IWA Water Policy data — above the world average of roughly 173 litres. A household of four is therefore using something in the region of 950 litres daily under typical conditions, though actual consumption varies widely.

As a rough guide, most installers recommend enough storage to cover at least 24–48 hours of reduced but functional use — drinking, cooking, sanitation — rather than full normal consumption. A 2,500-litre tank covers a family of four for about two to three days at reduced demand. Larger tanks obviously extend that buffer but add cost and require more structural consideration.

Household size	Daily use estimate (237 L/person)	2-day buffer (reduced demand, ~50%)
2 people	~474 L	~500 L
4 people	~948 L	~1,000 L
6 people	~1,422 L	~1,500 L

These are indicative starting points. A qualified installer will factor in your roof space, municipal inlet pressure, and whether you want the tank to serve the whole house or only critical outlets.

Boreholes: A Different Calculation

Some homeowners skip storage entirely and look to a borehole as their primary backup. A borehole draws directly from the groundwater table and is genuinely independent of municipal supply and, with a suitable pump and generator or solar setup, of Eskom too. Typical complete borehole systems in Johannesburg run R40,000–R150,000, with most falling between R60,000 and R100,000; the pump alone typically costs R15,000–R35,000 installed.

The catch is that Johannesburg’s geology is variable. Yield and water quality differ significantly across suburbs, and any water used for drinking must meet SANS 241 (2024 edition) — the South African drinking-water quality standard — which generally means treatment equipment and ongoing testing. A borehole is a longer-term, higher-upfront-cost solution; a tank-and-pump system is faster to install and predictable in what it delivers.

Whether a tank system or a borehole makes more sense depends heavily on your property and budget — getting quotes for both lets you compare the numbers directly. Get free quotes from local specialists — no obligation, no pressure.

What You Can Do Right Now, Before Installing Anything

Installation takes time and budget. In the interim, a few practical steps reduce your exposure:

• Fill containers when supply is good. A few large sealed containers in a utility room give you drinking water for a day or two at minimal cost.
• Note your outage schedule. Most load-shedding schedules are published in advance. Running dishwashers, washing machines, and topping up geysers before a scheduled slot is straightforward once the habit forms.
• Check your area’s pressure zone. Johannesburg Water’s website lists service interruptions by area. Knowing your zone helps you anticipate rather than react.
• Audit your usage. South Africa’s per-person average is high by international standards. Small reductions — shorter showers, fixing leaking taps — extend whatever storage buffer you do have.

None of this replaces a proper backup system, but it reduces the urgency of those first few hours after the pressure drops.