On 7 August 2026, the Puerto Rico Aqueduct and Sewer Authority (PRASA) began cutting water to more than 180,000 accounts in San Juan and six nearby municipalities, in rotating 48-hour blocks, until reservoirs recover.
The cause is drought. July 2026 was San Juan's driest month in more than 120 years of records, and by early August close to 68 percent of the island was in some level of drought, about a quarter of it severe. Governor Jenniffer González called the situation "out of our hands," and on the rainfall she is right. What she did not address is what happens to water after it falls: PRASA loses an estimated 59 to 65 percent of the water it treats before it reaches a customer. That loss is years old, and it is the part of the crisis that better monitoring and AI can reduce.
Who is affected and what relief is in place
The cuts cover San Juan, Carolina, Juncos, Gurabo, Trujillo Alto, Canóvanas and Loíza: 48 hours with water, then 48 hours without, on a schedule expected to run to at least the end of August. Households fill every container during the "on" window and ration it for cooking, washing and flushing during the "off" window.
FEMA has sent water trailers for an initial 30 days. The Public Housing Administration is installing community cisterns at housing complexes, and the Fire Department is delivering drinking water to some residents. These are necessary emergency measures, and none of them reduces the losses underground.
About three of every five gallons never reach a bill
Utilities call it non-revenue water: water that has been pumped, treated and pressurised, then lost to leaking pipes, faulty meters and ageing mains before anyone pays for it. At 59 to 65 percent, PRASA loses roughly three of every five gallons it treats.
Set that beside the rationing schedule. Recovering even a third of the loss would free a large volume of treated water without a new reservoir or any further cut to household use.
Until February 2026, PRASA ran its core network without SCADA, the supervisory control and data acquisition system that shows a utility pressure, flow and failures in real time. A $15.8 million federal package brought that monitoring online this year. Before that, leaks were found by about 16 leak detectives with listening equipment and around 100 field brigades of 12 workers each, testing pipes section by section. A leak could run for weeks before anyone found it.
Three AI methods that find leaks faster
Utilities in drought-prone regions already run these methods at scale.
Acoustic sensors on the pipes
Fixed sensors listen to the pipe around the clock. Machine learning models trained on recordings of leaks and normal flow flag the sound of a leak automatically, across far more pipe than 16 detectives can walk.
Pressure and flow analytics
An unexplained pressure drop in a district metering area is one of the earliest signs of a new leak, often visible in the data hours or days before water appears at the surface. A model trained on the network's normal pattern flags the change and narrows the fault to a short stretch of pipe, so one crew goes to one street instead of searching a neighbourhood.
Satellite and aerial surveys
Satellite radar and aerial thermal surveys can detect the soil moisture around large underground leaks across wide areas in one pass. Combined with sensor data, they give crews a ranked list of the leaks losing the most water.
The Core Argument
PRASA cannot make it rain. It can find where 59 to 65 percent of its treated water goes, and automated, AI-assisted detection is the practical way to do that across a network this size. Rationing buys time; repairing leaks recovers water every year after.
The $580 million meter programme needs an analytics layer
FEMA has approved a $580 million award to replace about 1.4 million mechanical meters with ultrasonic smart meters on an Advanced Metering Infrastructure network. Ultrasonic meters are more accurate than the mechanical ones and report use continuously, not once a month.
The meters alone save little water. Savings come from software that acts on their data:
- Flagging a customer-side leak when use stays high through the night.
- Catching a stuck or failed meter before it under-reports for months.
- Comparing the water entering a district with the total recorded by its meters, the same day, to show where losses are growing.
- Feeding the same readings into the acoustic and pressure models upstream.
PRASA's fiscal plan presents the rollout mainly as a route to accurate billing. Without the analytics, $580 million buys better bills. With them, PRASA gets a near real-time map of where its water goes missing.
Other Caribbean utilities face the same losses
An Auditor-General's report covered by the Jamaica Gleaner in 2026 found that Jamaica's National Water Commission loses between 40 and 60 percent of the water it treats. The NWC has run a non-revenue water reduction partnership in Kingston and St Andrew since 2015. Smaller island utilities have similar ageing networks and smaller monitoring budgets.
The dry conditions are regional this year. Jamaica issued a water prohibition order across seven parishes in August 2026, produce prices at Kingston's Coronation Market rose, and drought response costs across the region run into the hundreds of millions of dollars. Any utility entering a drought year with high losses risks its own rotating cuts.
Puerto Rico is building its monitoring in the middle of an emergency, which is the most expensive time to do it. A utility that installs leak detection and forecasting before the next dry season can recover water gradually and at lower cost.
Forecasting shortfalls and targeting rationing
Leak detection recovers lost water. Forecasting helps manage what is left. Models that combine satellite soil moisture, rainfall forecasts and reservoir drawdown can show a developing shortfall weeks before an emergency announcement, leaving time to phase in conservation.
When cuts are unavoidable, demand models built on smart meter data could show which district metering areas can go longer between supply and which, with hospitals, schools or dialysis patients, need priority. Rationing would still happen, with less hardship for the same volume saved.
The honest limit of this argument: I have no public figure for how much of PRASA's loss is leakage and how much is meter error or theft. That split decides how much water leak detection can recover, and PRASA should publish it.
What to do next
- PRASA: specify the analytics layer in the smart meter contracts now, so the meters, SCADA and leak detection models share one data platform from the first installation, and publish a breakdown of losses into leakage, meter error and theft.
- PRASA's operations team: pick the two district metering areas with the highest losses, install acoustic sensors there as a 90-day pilot, and report the volume recovered per dollar spent.
- Jamaica's NWC and other Caribbean utilities above 40 percent losses: start measuring minimum night flow in each metered district this dry season. It needs only flow meters and a spreadsheet, and it shows which districts to instrument first.
- The Caribbean Water and Wastewater Association: set up a shared register of leak-detection pilots and their results, so utilities do not each pay to learn the same lessons.
- Households in the rationing zone: check your own supply for leaks with the meter test in the FAQ below; a running toilet can waste much of what you stored for the dry days.
Frequently Asked Questions
Is all non-revenue water lost through leaks?
No. Non-revenue water has three parts: real losses from leaks and burst pipes, apparent losses from inaccurate meters, billing errors and illegal connections, and authorised use that is not billed, such as firefighting. Acoustic and pressure monitoring finds real losses; smart meters and billing analytics find apparent losses. A utility needs to know the split to put money where it recovers the most water.
What is a reasonable non-revenue water level for a utility?
Many well-run utilities keep non-revenue water below 20 percent, and the International Water Association's water balance method is the standard way to measure it so that utilities can be compared. Percentages alone can mislead, because a utility with high consumption looks better than one with low consumption for the same leaks. Engineers also track losses per connection per day, which is a fairer comparison.
How can a household check for leaks on its own side of the meter?
Turn off every tap and water-using appliance, note the meter reading or the position of its small leak indicator, and check again after 30 minutes without using any water. If it has moved, there is a leak between the meter and your taps. Toilets are the most common culprit: a few drops of food colouring in the tank that appear in the bowl without flushing mean the flapper valve is leaking.
What can a utility with a small budget do before buying AI systems?
Divide the network into district metering areas with a flow meter at each entry point, then measure minimum night flow, the flow between about 2 and 4 a.m., when legitimate use is lowest. High night flow points to leakage in that district. Reducing excess pressure in the network also cuts leakage and burst frequency at low cost, and the data gathered this way is what later AI models are trained on.
Where do Puerto Rico residents find the rationing schedule?
PRASA, known in Spanish as the Autoridad de Acueductos y Alcantarillados (AAA), publishes the rotation by sector on its official website and social media accounts. Check your sector each week, because schedules change as reservoir levels move. For emergency water delivery, contact your municipality's emergency management office.