Water cisterns: the question every Puerto Rico buyer should ask

Why it matters

In August 2026, the water authority began rationing service on a 48 hours on, 48 hours off schedule in San Juan, Carolina, Canóvanas, Loíza, Trujillo Alto, Gurabo, and Juncos because of drought at the Carraízo reservoir. Power outages can also interrupt water service, as the April 2025 blackout did for more than 400,000 customers.

A cistern stores water on site so the house keeps running through both.

The questions

• Capacity. Gallons, and how many days that covers for your household.
• Whole house? Does it feed every fixture, or only some?
• Pump and pressure tank. Their age, and whether the pump is on the generator circuit.
• Filling. How it refills from the city supply, and whether it can be filled by truck.
• Water quality. Filtration, treatment, and when the tank was last cleaned.
• Condominiums. Whether the building has a cistern, its size, and whether it serves units or only common areas.

Keeping it safe

The CDC advises filling a cistern before a storm, diverting stormwater away from it, and disinfecting it if contamination is possible, and recommends keeping a separate emergency supply of one gallon per person per day. Ask when the tank was last cleaned and how it is treated.

How ORAVISTA records it

Our records list whether a cistern exists and its capacity in gallons, marked Verified, Unverified, or Unknown with source and date.

Questions

Do Puerto Rico homes have water cisterns?

Many do, especially newer and higher end homes, but not all. Ask for the capacity in gallons and whether it serves the whole house.

Why do Puerto Rico homes need cisterns?

Water service can be interrupted by drought rationing, as in the Carraízo rationing of August 2026, and by power outages. A cistern keeps water flowing in the meantime.