Pressure Under Control, Less Leakage: How to Cut Losses and Water Hammer in Your Network

Every litre of treated water lost in the network leaves a cost behind: treatment chemicals, pumping energy and infrastructure wear, all for a product that never reaches the customer. International references cite average leakage of 26% in Europe, 30% or more in some large North American cities, and up to 70% in developing nations. Percentages are not the best metric for comparing networks, but the message is clear: water utilities across Mexico and Latin America, facing growing demand with limited budgets, need to make loss reduction a priority.

Replacing all aging pipe is not realistic. The alternative is to prioritize and extend asset life. Two measures make that possible with a gradual investment: pressure management and transient monitoring.

Why pressure is the most direct lever

Lower pressure means lower leakage. At night demand drops, friction losses fall and network pressure rises; swings of 15 to 30 psi (1 to 2 bar) between daytime and nighttime averages are not uncommon. Customers near the source also tend to receive more pressure than needed to serve the farthest or highest ones. The principle is to deliver just enough pressure at the critical point.

The AWWA M36 manual (Water Audits and Loss Control Programs) distinguishes three types of leakage: background, unreported and reported. According to that manual, pressure reduction and pressure stabilization are the only proven proactive measures that affect all three. In aging networks the effect can be larger, because pipes tolerate daily pressure fluctuations less and less. Actual results depend on each network, so they should be measured in the field.

Transients: the damage you cannot see

A transient, or water hammer, is a rapid pressure change that travels through the network. It is triggered by actions such as closing a valve, stopping a pump abruptly or sudden demand changes. When pumping is concentrated at night to take advantage of lower electricity rates, the likelihood of transients rises too.

Some are severe: they can burst a pipe or let contaminants in. Most, however, do not break anything right away; they fatigue the pipe until a leak appears. Recording them helps detect poorly configured control valves, unauthorized hydrant use or the effects of operational changes, so the cause can be corrected before a failure.

From theory to operations with Marfel

Applying these concepts requires control and measurement:

• Control: the IP pressure reducing valve manages inlet pressure to a district metered area (DMA).
• Logging: IoT data loggers collect pressure and other variables in the field.
• Telemetry: data loggers and telemetry systems send data and alarms remotely so teams can act in time.
• Flow and leaks: ultrasonic and electromagnetic flow measurement and leak detection quantify the effect and locate what remains.

For transients, verify that the equipment offers sufficient sampling frequency, threshold triggering, memory for relevant events, battery life and remote communication.

How to start: a pilot in one DMA

The best way to justify a larger investment is to show results in a single sector. Define a DMA with flow and pressure measurement, install pressure control and compare before and after:

Variable	What it reveals	What it is for
Critical point pressure	Whether minimum service pressure is maintained	Adjusting the PRV setpoint
Minimum night flow	The sector's leakage level	Measuring the effect of the reduction
Transients	Events that fatigue the pipe	Correcting valve and pumping operations
Failure frequency	Medium-term outcome	Justifying scale-up

With that data, the utility can replicate the strategy in the highest-risk zones on an objective return-on-investment basis.

Water for future generations

At Marfel we work to guarantee access to water for future generations by increasing network efficiency with innovative solutions. To evaluate a pressure management and transient monitoring pilot, write to us at contacto@marfel.mx or explore our solutions at marfel.mx.