Backup Water for Families with Young Children

When the municipal supply drops or pressure disappears, most adults adapt quickly — shorter showers, fewer rinses, a bit of inconvenience. Households with infants and toddlers face a different problem. Formula feeds cannot wait, sterilising cannot be skipped, and small children are far more vulnerable to waterborne illness than healthy adults. Planning backup water for a family with young children is a more demanding exercise than it looks, and the stakes for getting it wrong are higher.

Why young children change the calculation entirely

South Africans use roughly 237 litres per person per day on average — already above the global average of around 173 litres. But that figure is an adult-weighted national average. Infants add relatively little in direct consumption, yet they add disproportionately to quality-critical demand: every bottle of formula, every rinse of a feeding implement, every clean-up after a nappy change draws on water that must be safe to drink or safe for skin contact.

The practical upshot is that a family of two adults and two young children should not simply multiply 237 litres by four and call it done. You need to layer in:

• Formula water — boiled or pre-treated, measured carefully per feed
• Sterilising water — for bottles, teats and any surface that touches food
• Extra hygiene water — hand-washing frequency is much higher with small children in the house
• Cooking and food prep — puréed foods and soft solids often require more water than adult meals

For a realistic picture of how much water a household actually moves through each day, the breakdown in how much water a family of four really uses is a useful starting point before you size any storage system.

Water quality is not negotiable — SANS 241 matters here

The South African drinking-water quality standard is SANS 241, last revised in 2024. Any water used for infant formula or sterilising should meet or exceed these parameters — chemical limits, microbiological thresholds, the lot. Municipal water is treated to this standard, but stored water can degrade: UV light promotes algae, stagnant warm water encourages bacterial growth, and improperly sealed tanks introduce contamination.

For families using borehole water as a backup or primary supply, the quality question is even more pressing. Borehole water in Johannesburg’s residential areas is not automatically safe for infants. It should be independently tested against SANS 241 before it is used for formula or sterilising, and a treatment stage — at minimum UV sterilisation, potentially reverse osmosis — should be part of the system design.

The detailed guidance on safe drinking water for babies covers what to test for and when to apply additional treatment, which is worth reading before you commit to any particular setup.

What backup system options actually look like for families

Most Johannesburg households planning backup water land on one of three approaches:

Tank-and-pump systems are the most common entry point. A JoJo or similar polyethylene tank stores municipal water when supply is available; a pressure pump delivers it to taps when the mains drop. Costs for a full backup tank-and-pump setup typically run R20,000–R40,000 for a standard installation, with whole-house systems around R55,000. For a family with young children, sizing the tank generously — enough for at least three to four days of realistic family consumption — is more important than saving a few thousand rand on a smaller vessel.

Borehole systems provide a more independent supply but are a bigger investment. Complete borehole installations in Johannesburg typically run R40,000–R150,000, with most falling between R60,000 and R100,000. The pump alone is typically R15,000–R35,000 installed. Boreholes make more sense when load-shedding and municipal outages are frequent enough that a tank empties before it can be refilled, or when you want long-term independence from the grid.

Rainwater harvesting can supplement but should not be the primary backup for infant households without robust filtration and testing. Roof runoff carries particulates, bird waste and dissolved contaminants that require proper treatment before they are safe for vulnerable users.

For a fuller comparison of these options and how they interact with each other, the backup water systems overview sets out the trade-offs clearly.

Sizing a backup system for young children means getting the volume and water quality right from the start. Compare 3 free quotes — vetted installers, no obligation.

Practical sizing guidance for households with infants

Rather than relying on generic rules of thumb, work through a rough daily demand figure before you speak to any installer. As a starting framework:

Household member	Rough daily water demand (quality-critical)
Adult	15–25 litres drinking/cooking
Toddler (1–3 years)	10–15 litres drinking, cooking, hygiene
Infant on formula	5–10 litres formula + sterilising alone
General household hygiene (shared)	20–40 litres across the household

These are rough guides — confirm the totals with your installer and adjust for your actual usage patterns. The point is that an infant on formula alone can drive meaningful additional demand on quality-critical water, quite apart from general household consumption.

For most families with one infant and one toddler, a storage buffer of at least 500–1,000 litres of potable-quality water is a sensible minimum. If Johannesburg’s reservoir system holds roughly 27 hours of citywide buffer — as reported figures indicate — a localised outage of 48–72 hours is entirely plausible, and your household reserve should reflect that.

Maintaining your backup supply safely

A tank that sits full and unmanaged is not a safe backup for a household with young children. Storage tanks should be:

• Opaque or UV-resistant to limit algae growth
• Sealed against insects and debris — mesh-covered inlets as a minimum
• Rotated regularly — water should not sit unused for weeks without turnover
• Tested periodically if you are relying on borehole or rainwater sources

If you add a chlorine dosing system or UV steriliser, make sure it is sized correctly for the flow rate and maintained according to the manufacturer’s schedule. A malfunctioning treatment stage gives a false sense of security, which is worse than no treatment at all.

For municipal-source tank systems, the water that enters your tank is treated to SANS 241 standards. Your job is to keep it that way during storage and delivery.

If you're ready to compare options for your household's specific needs, take two minutes to tell us about your setup. Get free installer quotes — no commitment required.

Getting the conversation right with your installer

When you contact installers for quotes, be specific about your household composition. A supplier quoting a generic family system may not account for the additional quality requirements and storage volume that come with infants and toddlers. Ask directly:

• What tank volume do you recommend for our specific household makeup, and why?
• What treatment does the water go through before it reaches our taps?
• How does the system handle water quality if the municipal feed is interrupted for more than 48 hours?
• What maintenance schedule does this system require, and what does it cost annually?

Johannesburg Water’s non-revenue water figure of 44.8% — audited for 2024/25 — reflects a distribution network under significant stress. Supply interruptions are not hypothetical for most Johannesburg suburbs. For a household with young children, treating backup water planning as essential infrastructure rather than optional preparedness is simply the practical position.