The Leak Hunters

Jordan’s largest untapped water source is Jordan’s own pipes.

Jordan has about sixty cubic metres of renewable water per person per year. Hydrologists use the phrase absolute scarcity below five hundred cubic metres per person per year. For years, the country has been building the case for a multi-billion-euro desalination plant on the Red Sea, with a pipeline some 445 kilometres north to Amman, because there is no other source left to develop.

There is another way to look at Jordan’s water shortage. Roughly half the water it puts into its municipal networks never reaches a paying customer. In 2022, that amounted to about 260 million cubic metres, according to official figures from its Central NRW Unit. That is close to the 300 million cubic metres a year that the Aqaba to Amman desalination and conveyance project is designed to deliver. The lost water is already inside the country, already treated, already pressurised and already paid for.

Jordan is an extreme case, but it is not an outlier. Lebanon’s own water strategy puts non-revenue water at about half of supply. Algeria lost some 40% in distribution in 2004. Urban networks in Saudi Arabia lose about a quarter, as do Tunisia’s drinking-water networks and Morocco’s urban distribution systems. The region that has invested more heavily than anywhere on earth in making water from the sea is also losing a very large share of that water between the treatment plant and the tap.

Half the problem never leaves the pipe. It leaves the ledger.

The technical term is non-revenue water, and the distinction it makes is more important than it may sound. Non-revenue water is not the same as leakage. It is all the water a utility puts into its network but receives no revenue for. The total divides into two different problems, each requiring a different solution.

Real losses are physical. Water escapes through cracked mains, corroded service connections, failed joints and overflowing reservoirs. Most of it never reaches the surface. A service pipe that is leaking into gravel beneath a road can continue doing so for years without anyone above ground noticing. This is the part that engineers can address with valves, sensors and excavators.

Apparent losses are commercial. The water reaches somebody’s tap, but the money does not reach the utility. Meters under-register, especially at low flows and as they age. Some connections have no meter at all. Bills may be estimated, mis-read, assigned to the wrong account or simply not collected. Replacing pipes cannot solve any of these problems.

The first task is to identify the split between physical and commercial losses, because the two failures cost very different amounts to fix. A utility that spends a hundred million dollars replacing mains when two-thirds of its losses are commercial has bought itself very little water. The International Water Association’s water balance, the framework described below, exists to prevent that mistake. World Bank guidance treats it as the starting point for any loss-reduction strategy.

Structure follows the International Water Association’s standard water balance, the accounting framework almost every utility and lender now uses. The percentages illustrate a high-loss network rather than any single utility, and every band is drawn at its true share, which is why the two thinnest are named in the key rather than labelled in place.

At three in the morning, whatever is still moving is mostly leaking.

There is a simple way to measure how much a district is leaking, and it depends on measuring the network while people are asleep. The utility takes a defined section of the network, typically 500 to 3,000 properties in a city, and closes every valve into it except one. This is a district metered area, a core technique of modern leakage control. A flow meter is fitted to the one open connection and records continuously. The utility then examines the reading at three in the morning.

At three in the morning, almost nobody is using water. Legitimate night-time consumption in a residential district is small and reasonably predictable: a few toilets, a handful of night-shift workers and some commercial premises. If the meter shows that 26 cubic metres an hour are still flowing into the district, while legitimate night-time demand is 8, the remaining 18 are leaking into the ground. Leakage continues during the day, unlike demand. That 18 therefore runs every hour of every day, amounting to about 158,000 cubic metres a year from one district.

Illustrative profile for a district metered area of roughly 1,500 connections. The technique is standard: isolate a district, meter what goes in, and read the flow at the hour when almost nobody is using water.

Minimum night flow shows how much water a district is losing. It does not show where the leak is. Locating the leak is a separate problem, and the past decade has changed how utilities tackle it.

A pressurised leak makes a noise, and the pipe carries it.

Water forced through a crack makes the pipe wall vibrate, and that vibration travels along the pipe, particularly well along metal. The classic tools are noise loggers, correlators and ground microphones. These are sensors fixed to valves or hydrants that record the sound of the network overnight.

Two sensors placed on either side of a suspected leak can do more than detect the sound. The same sound reaches each sensor at a slightly different time. If the speed of sound through that pipe material is known, the difference in arrival time reveals the leak’s distance from the sensors. The method requires adequate pressure and good transmission of noise along the pipe, but where it works, it can mean digging at one point in the road rather than twenty.

The newest layer is orbital. Radar from a satellite penetrates the ground, and an algorithm tuned to treated drinking water flags places where water may be escaping. Its supplier says it can detect leaks as small as half a litre a minute. Commercial services now sell utilities a map of suspected leaks across an entire city, reducing a large network to a list of points worth investigating. The technology does not find the leak itself. It tells the crew which streets to walk.

The cheapest water in the region is bought with a valve.

Before anyone digs, pressure management offers a relatively cheap intervention that World Bank guidance calls an often underestimated option. Leakage is a function of pressure. Increasing the pressure makes every existing hole pass more water, and some leak paths, such as splits in plastic pipe, also open wider under load. For a fixed hole, flow rises only with the square root of pressure. Real networks are usually much more sensitive than that, which is why practitioners use the leakage exponent rather than a simple ratio. In plain terms, cutting excess pressure by a third can cut leakage by rather more than a third.

Many networks are over-pressurised for much of the day. They are designed for the morning peak and for the highest point in the zone. At two in the morning, at the bottom of the hill, the pipes can therefore be carrying far more pressure, or head, than anyone needs. A pressure-reducing valve with a controller that lowers the setting overnight fixes that for the price of a valve. It also reduces bursts. UK data show mains burst frequency rising rapidly once pressure exceeds about 35 to 40 metres of head.

Desalination is the published benchmark at the top of that ladder. Dubai’s Hassyan plant set a record tariff of US$0.277 a cubic metre in 2020, while World Bank data put typical seawater plant costs at roughly US$1 to US$1.40, depending on the sea.

A meter that under-registers fails silently, and never in the utility’s favour.

In much of the region, a large part of the problem is not underground. It is in the meter, the ledger and enforcement. Small turbines under-register at low flows, precisely the flows produced by a rooftop tank as its float valve closes. The error grows as the meter ages. Under intermittent supply, Jordan’s own loss-reduction policy expects meters to under-register within two years. Nobody notices because the failure is silent and works against the utility.

Then there is water that is simply taken. Illegal connections are usually described as theft, which is accurate but unhelpful. People tap a main when the formal route to a connection is slow, expensive or closed to them. Where enforcement is selective, an illegal connection is a rational response to a rationed service. Jordan’s campaigns against illegal wells and water-line violations saved 31.5 million cubic metres between January and early November 2025, but they are enforcement campaigns directed at a structural condition.

Dubai loses 4.5%. The region’s conditions are not the problem.

Comparing utilities on non-revenue water is harder than it looks. Countries measure it differently, publish it selectively and report it as a percentage. That measure flatters any utility whose customers use a lot of water, because the denominator is larger. Practitioners therefore prefer volume per connection per day. The percentages still show something real, however, because the differences between them are far too wide to be explained by definitions alone.

Two things stand out. The first is that the Gulf has already shown that low losses are possible in a MENA climate, with MENA soils and MENA construction practice. Dubai reports 4.5% and Qatar reports technical losses below the same mark. Nobody can now argue that the region’s conditions make low loss rates impossible.

The second is that the countries with the least water lose the most of it. That is not a coincidence, and the reason is the subject of the next chapter.

A desalination plant is a building a minister can stand in front of.

The technology described here has existed for decades and is well understood. MENA does not lose so much water because its engineers do not know how to find leaks.

Start with the most damaging single factor: intermittent supply. When a utility cannot meet demand, it rations water through rotation. Jordan’s utilities have been pushed on to intermittent supply across the country. Some Amman residents say water reaches their neighbourhood once a week. Rationing then makes the losses worse in three separate ways. Switching a network on and off damages it. In Cyprus, two years of rationing caused additional pipe breaks and left leakage higher for years afterwards. Households respond by installing rooftop tanks, which fill through float valves at flows too low for many meters to register. An intermittent network also cannot be measured properly, because a district without water at night has no minimum night flow. The utility loses its instrument at the same moment that it loses control.

Then there is the money. Tariffs across much of the region are set well below the cost of supply. On World Bank figures, the price charged covers about 35 percent of the cost of producing conventional water. A utility that recovers only a fraction of its costs cannot fund a leakage programme, replace its meter fleet or pay enough to retain the people who know where the valves are. Its losses rise, its revenue falls further and the case for the next crackdown becomes weaker rather than stronger.

There is also a plainer problem. Non-revenue water is an operating expenditure line with no ribbon to cut. A desalination plant is a building where a minister can stand for photographs. Twelve thousand replaced service connections and a reprogrammed pressure-reducing valve are not, even when they deliver water for far less money.

Phnom Penh went from 72% lost to six, and the pipes came last.

The counter-example that matters is not in this region. In 1993, the water utility of Phnom Penh was losing 72% of what it produced, reached only a fifth of the city, supplied water for about ten hours a day and barely covered half its operating costs. Fifteen years later, it was losing 6%, covering 90% of its area around the clock, collecting on 99.9% of its bills and charging tariffs set for full cost recovery. Losses have since settled at about 8.75%.

What changed first was not the pipes. Corrupt staff, including employees who installed connections illegally, were removed. A 1994 survey found 13,722 connections missing from the utility’s records, allowing the records to be corrected. Every connection was metered. A 1996 decree gave the utility administrative and financial autonomy, so that the additional revenue stayed in the network. The engineering followed governance, in that order.

• 1993

  The starting point

  The utility loses 72% of what it produces, reaches a fifth of the city, supplies water about ten hours a day and covers barely half its operating costs.

• 1994

  The books, first

  A survey finds 13,722 connections missing from the utility’s records. Staff who had installed connections illegally are removed.

• 1996

  Autonomy

  A decree gives the utility administrative and financial autonomy, so that revenue it raises stays in the network.

• 2008

  The result

  Losses are down to 6%, coverage is 90% of the city around the clock, collection runs at 99.9%, and tariffs are set for full cost recovery.

• since

  Held, not won once

  Losses have settled at about 8.75%, which is what maintaining the position looks like.

For MENA, the prize is straightforward to size. Domestic water withdrawals across the Arab states alone came to about 31 billion cubic metres in 2022. If losses on that water averaged around 40% and were brought down to 25%, which is Jordan’s own 2040 target rather than a fantasy, the change would free on the order of four to five billion cubic metres a year. That is more than a quarter of the region’s installed desalination capacity of about 45 million cubic metres a day, and it would require no new intake, no new membrane, no new power station and no additional brine returned to the Gulf.

It would, however, require utilities to be allowed to charge something closer to what water costs, keep the proceeds, and meter and bill customers they currently do not. Those are political decisions rather than engineering decisions, and none of the region’s utilities can take them alone. Until those decisions are taken, the region will keep buying its next cubic metre from the sea at a higher price than the water already running beneath its streets.