Is a Borehole Worth It in Johannesburg? The Payback Maths

Johannesburg’s water infrastructure is under real pressure. Johannesburg Water’s own audited figures show non-revenue water — supply lost to leaks, theft, and metering errors — running at 44.8% for 2024/25. The city’s reservoir system holds roughly 27 hours of citywide storage buffer. Put those two facts together and you have a network that wastes nearly half of what it pumps while carrying less than two days of emergency reserve. Against that backdrop, the question of whether a borehole is worth it is only partly about rands and cents.

This article runs the honest numbers, flags where the maths breaks down, and helps you decide whether drilling makes sense for your specific situation.

What a Borehole Actually Costs

Before you can work out payback, you need a realistic cost. Complete borehole systems in Johannesburg typically run R40,000–R150,000, with most residential installations falling between R60,000 and R100,000 once you include drilling, casing, a pump, pressure tank, filtration, and connection to the house. The pump alone — installed — typically costs R15,000–R35,000.

That range is wide because geology varies dramatically across Johannesburg. Drilling depth, yield, and water quality differ suburb by suburb. A borehole in one part of Sandton may hit a good aquifer at 40 metres; a few kilometres away it may need to go past 100 metres for a usable yield. There is no way to know without a site assessment and a proper quote. For a detailed breakdown of what drives those costs, read our borehole cost guide for Johannesburg.

Building the Payback Calculation

Payback is simple in principle: divide your capital cost by your annual saving. In practice, three variables are hard to pin down.

Your current municipal water bill. South Africans use around 237 litres per person per day on average (above the global average of roughly 173 litres). A household of four using near that average consumes roughly 28,000–30,000 litres per month. Johannesburg Water’s tariff structure uses rising blocks, so your saving per kilolitre depends on how much you use. Pull your last six statements and calculate an average cost per kilolitre — that is your starting point.

Borehole yield. If your borehole yields enough to replace all outdoor use (garden, pool top-up, car washing) and some indoor use, your saving is material. If it yields 500 litres per hour during a two-hour daily pumping window, you are replacing perhaps 1,000 litres a day — useful, but not transformative for a large household.

Ongoing running costs. Electricity to run the pump, an annual service, and periodic filter replacement all reduce net savings. As a rough guide, budget a few thousand rand per year in operating costs, though the exact figure depends on pump size, usage, and whether you are on a TOU electricity tariff. Get a quote-specific estimate rather than relying on any generic number.

A worked example (illustrative only)

Scenario	Capital cost	Annual net saving	Simple payback
Modest yield, replaces outdoor use	R65,000	R5,000–R8,000	8–13 years
Good yield, replaces most garden + some indoor	R85,000	R10,000–R15,000	6–9 years
High yield, significant indoor substitution	R110,000	R15,000–R22,000	5–7 years

These ranges are illustrative. Your actual numbers depend on current tariffs, your household’s consumption, and what your aquifer delivers. Treat them as a structure for thinking, not a forecast.

When the Maths Works Against You

A borehole is unlikely to pay back well if:

• Your yield is low. A borehole that produces 200 litres per hour is better than nothing in a crisis, but it will not move your water bill meaningfully.
• Your water bill is already low. If your household uses modest amounts and stays in the lower tariff blocks, the rand saving per kilolitre is smaller.
• Geology requires deep drilling. Very deep boreholes with marginal yield push capital costs toward the top of the range without proportionally better returns.
• Water quality needs heavy treatment. High iron, hardness, or biological contamination — all of which occur in parts of Johannesburg — requires filtration that adds capital and running costs. SANS 241 (2024 edition) is the South African drinking-water quality standard; borehole water used indoors should be tested and treated to meet it.

If you want real numbers for your property rather than ranges, the fastest way is a site-specific quote. Compare 3 free quotes — vetted installers, no obligation.

The Case That Isn’t About Payback

Here is what the payback calculation misses: water security has a value that doesn’t show up in rand savings.

With only about 27 hours of citywide reservoir buffer, a significant pipe burst, pump-station failure, or load-shedding event affecting water treatment can leave suburbs dry within a day. Johannesburg Water’s non-revenue water rate of 44.8% reflects a network under chronic stress. These are not hypothetical risks — most Johannesburg homeowners have experienced unplanned supply interruptions.

A borehole, combined with a storage tank, means your household keeps functioning when the municipal tap runs dry. For households with elderly residents, home-based businesses, or simply a low tolerance for disruption, that resilience has real value even if the financial payback stretches to ten years.

The comparison that often makes more sense is not borehole versus municipal supply, but borehole versus a backup tank-and-pump system. A tank-and-pump setup typically costs R20,000–R40,000 (whole-house systems around R55,000), gives you storage buffer, but leaves you entirely dependent on municipal quality and quantity. A borehole costs more upfront but gives you an independent source. Which is right depends on your risk appetite and your budget.

What Affects Whether Your Borehole Will Deliver

Before committing, it is worth understanding the factors you cannot fully control:

• Aquifer depth and yield are site-specific and only confirmed after drilling. A reputable driller will do a hydrogeological desktop assessment before quoting, but no one guarantees yield.
• Seasonal variation — some Johannesburg aquifers recover more slowly in winter, affecting sustained yield.
• Neighbouring boreholes — high-density residential drilling in some suburbs has drawn down local water tables.
• Borehole lifespan — casings, pumps, and seals have finite lives. Budget for pump replacement roughly every 8–15 years as a rough guide, though this varies considerably by make, usage, and water quality.

Knowing your local geology before you commit can save you from a costly dry hole. Get quotes from local drillers who know your area — no obligation, takes two minutes.

Making the Decision

A borehole is worth it in Johannesburg if: your property sits on a reasonably productive aquifer, your household uses enough water to generate meaningful savings, and — critically — you value supply independence as well as cost reduction. For many homeowners in the northern suburbs, that combination stacks up.

It is less clearly worth it if you are purely chasing payback with no buffer for the uncertainty in yield, quality, and ongoing costs. The honest answer is that payback timelines of 5–12 years are realistic for well-situated properties, but the numbers depend entirely on your specific geology, your bill, and the quality of your installation.

The starting point is always an on-site assessment and at least two or three quotes. Costs and yields vary enough across Johannesburg that no range in an article — including this one — substitutes for numbers specific to your stand.