Guide · reviewed August 7, 2026

Buying a Catchment Home in Hawaiʻi

Inspect the tank, roof, gutters, filtration, disinfection, pump, pressure system, water quality, and maintenance records.

Comparable facts

Catchment inspection path comparison

Start at the roof and follow the water through gutters, inlet screening, storage, pump, pressure equipment, filtration, treatment, and every tap. A clean-looking tank does not prove the complete system is maintained.

Tank and storageTank material, capacity, age, liner condition, cover, overflow, and access are documented.

Roof and guttersRoof and gutter materials are suitable and reasonably clean.

Inlet controlsFirst-flush or debris-control components are present and understood.

Pump and pressurePump, pressure tank, controls, bypasses, and backup-water plan are tested.

Treatment stagesSediment and treatment stages are identified with replacement dates.

Testing and recordsRecent water-quality testing and maintenance records are available.

Household demandHousehold demand is compared with tank storage and local rainfall variability.

Practical guidance

Inspect the whole water path

Take this to the property

Catchment-home inspection checklist

Tank material, capacity, age, liner condition, cover, overflow, and access are documented.Roof and gutter materials are suitable and reasonably clean.First-flush or debris-control components are present and understood.Pump, pressure tank, controls, bypasses, and backup-water plan are tested.Sediment and treatment stages are identified with replacement dates.Recent water-quality testing and maintenance records are available.Tank cleaning, filter replacement, roof cleaning, and disinfection routines are explained.Household demand is compared with tank storage and local rainfall variability.

Practical guidance

Documents and questions to request

Tank, pump, filter, ultraviolet, and treatment equipment manuals.
Dates for tank cleaning, cartridge changes, lamp replacement, repairs, and water testing.
Water-hauling history and the household conditions that caused shortages.
Who maintains the system and where replacement parts are obtained.
What happens during a power outage or pump failure.

Related tool

Use the existing sizing calculator

Estimate storage and household demand with the Hawaiʻi Water Catchment Sizing + Cost Calculator. Replace its defaults with the actual roof area, tank size, household use, and local conditions.