Water Loss Investigation: Aloe Ridge Estate

Capital City Housing manages Aloe Ridge, a multi-village estate. By 2024, the estate was facing four problems at once.

• Significant, expensive water losses across the network
• Ageing pipework (Class 6, with limited bedding quality) already near the end of its safe working life
• Outdated or incomplete drawings of the network
• No clear direction on whether to repair, manage pressure down, or fully replace key sections, each option carrying a very different cost

Capital City Housing needed hard evidence behind any decision that carried this much financial weight.

Our Brief

African Crake Projects, working with Ant Consult, carried out a full investigation of Villages 1 and 2. We set out to do four things.

1. Rebuild accurate maps of the potable water, fire, sewer, and stormwater networks.
2. Quantify water losses and distinguish leakage from legitimate consumption.
3. Find the critical leaks and weaknesses in the fire and potable systems.
4. Recommend fixes with a cost estimate attached to each.

What We Did

We began on site, physically verifying pipe sizes, materials, and condition rather than relying on the estate's existing records, and mapping every valve, meter, hydrant, and other component across the network.

That work produced a complete digital record of the potable water, fire, sewer, and stormwater networks, delivered as maps and drawings Capital City Housing's team can use directly.

It replaced the outdated, incomplete drawings the estate had been working from, and Capital City Housing now uses it as its primary record for the network, the reference point for future maintenance and decisions.

We then installed monitoring to track flow and pressure across the network over time, and built a computer model of how the system should behave under normal conditions. Comparing what the model predicted against what we measured on site is what let us pinpoint exactly where leaks, faults, unmetered connections, and pressure problems were happening, rather than guessing from the paperwork.

Key Insights

What We Found in Village 1

We found an unmetered pipe (Ø250 mm bypass) connecting Village 1 and Village 2 that nobody knew was open, and closed it. Beyond that, the potable water system was losing roughly 147,000 ℓ/day, close to half of everything flowing into the network, before it reached a single tap. The fire system was leaking too, a smaller but steady loss of around 43,000 ℓ/day.

Pressure was a problem in both systems. In the potable network, pressure was running as high as 120 m in places, close to double the 60 m rating of the pipework, the likely explanation for repeated bursts and failures. The fire system was running similarly high, modelled at up to 118 m.

What We Found in Village 2

Village 2 told a different story. Leakage in the potable system was close to zero, and the fire system showed almost no losses either. The only issue was pressure running higher than it needed to, with room to bring it down safely by roughly 20 to 30 m, about 2 to 3 bar, without affecting residents' water supply.

What We Recommended

The core fix in both villages was pressure reducing valves, PRVs, equipment that automatically holds network pressure at a safe set point instead of letting it run unchecked.

Village 1

• Keep the newly discovered bypass permanently closed
• Install a new PRV on the incoming line, set to around 30 m
• Repair the failed PRV on the Village 1 MK section

Village 2

• Install PRVs on the incoming lines to trim pressure down by 20 to 30 m

Both villages

• Strengthen controls to stop residents drawing domestic water from fire lines
• Focus further leak detection only on the areas the data pointed to, rather than checking the whole network blind

What It Meant for the Client

Capital City Housing left with a definitive picture of exactly where water was being lost across the network, and just as importantly, where it was not.

• Confidence to avoid unnecessary large-scale replacement work in Village 2
• A precise, location-specific picture of Village 1's leaks and pressure risk, tied to exact locations and readings rather than general estimates
• A single, costed roadmap that cut the water being lost before it reaches a paying customer, reduced the risk of bursts on pipework running at higher pressure than it was built for, protected the water service residents depend on, and gave Capital City Housing the engineering evidence to justify future capital spend

The Aloe Ridge investigation turned a poorly documented, high-loss system into an asset management plan built on real data, giving Capital City Housing the confidence to prioritise where to spend next.