Water Cuts: Plan the Backup System, Not Just the Tank

Imagine a Kathu guesthouse preparing for a full weekend. There is a tank beside the building, but nobody has checked whether the showers receive adequate pressure when the municipal supply is unavailable. This illustrative example is a useful planning exercise: storage and delivery must be considered together.

Decide what must keep running

Make an essentials list first: drinking and cooking, toilets, showers, cleaning, or business equipment. Separate these from uses you can postpone. Our recommendation is to estimate actual daily demand from records or measurements rather than choose a tank purely because it fits the available corner.

For a worked planning example, assume essential consumption of 600 litres per day and two days of cover. The calculated usable storage requirement is 600 × 2 = 1,200 litres. This is an assumption-based example, not a promise about your household’s consumption. Allow the installer to account for inaccessible volume and operating levels before selecting nominal tank capacity.

Ask for an installation drawing

JoJo’s municipal-backup guidance covers the tank, pump, float valve, isolation valves, connecting pipework and non-return valves. It also calls for a sound, smooth, level supporting surface. Follow the instructions for the particular tank and have the proposed installation checked for your site. [1]

Mark the municipal inlet, tank outlet, pump, house feed and maintenance access on the drawing. Ask how the plumber will prevent backflow and comply with the applicable local requirements. South African water-reticulation training recognises that different backflow-prevention methods suit different situations. [2]

Include the power question

Ask the installer what happens when water and electricity are unavailable at the same time. If the design relies on a booster pump, specify how it will be powered or which alternative supply arrangements will be available. Request a demonstration under the intended operating conditions before accepting handover.

Keep the system serviceable

Plan a maintenance checklist covering the lid, inlet, overflow, leaks, valve operation and water turnover. Arrange cleaning and disinfection when required. WHO’s tank guidance treats cleaning, disinfection and preparation for reuse as distinct steps; it is not simply a matter of adding chlorine to a dirty tank. [3]

References and further reading

• [1] JoJo: Municipal Backup Water Storage Solutions
• [2] SAQA: Pressure Zones and Backflow Prevention in Water Reticulation
• [3] WHO: Cleaning and Disinfecting Water Storage Tanks and Tankers

Cover photograph: Wallace Chuck / Pexels. Illustrative stock image, not a Water Nest project. Image licence.