Seawater Desalination RO Watermaker 100 GPD | 380 LPD

Seawater reverse osmosis (SWRO) watermakers convert raw ocean water into potable fresh water by forcing high-salinity feed water through semi-permeable RO membranes at pressures between 800 and 1,200 PSI. At that pressure differential, dissolved salts, bacteria, and most trace contaminants are rejected by the membrane surface. Typical salt rejection runs 99.4 to 99.7%, producing permeate water below 500 ppm TDS – well within WHO and EPA potable water guidelines, and often below 100 ppm on well-maintained systems with quality seawater feed.

Each AMPAC SWRO system ships as a fully integrated skid assembly. The skid includes the high-pressure pump, pressure vessels and membranes, low-pressure feed pump, instrumentation, and a control panel with automatic shutdown on high/low pressure faults and feed water TDS alarm. All interconnecting high-pressure plumbing is completed at the factory. Field connections are limited to feed water inlet, product water outlet, brine discharge, electrical supply, and pre-treatment integration points.

Pre-treatment required

Pre-treatment is required on every unit. A multimedia or sand filter removes suspended solids and turbidity. A 5-micron cartridge filter provides the final barrier before the high-pressure pump. Antiscalant dosing is recommended, particularly in coastal areas where feed water chemistry varies with tides, algal blooms, or seasonal runoff. Skipping pre-treatment shortens membrane life and voids warranty coverage on the pressure vessels.

Recovery rate on seawater systems runs 35 to 45%. For every 100 gallons fed to the membranes, roughly 35 to 45 gallons become product water; the remainder exits as concentrate brine. Plan feed water supply and brine discharge routing before installation. Energy consumption typically runs 4 to 8 kWh per 1,000 liters of product water depending on feed conditions.

This Unit: 100 GPD / 380 LPD

The 100 GPD / 380 LPD unit is the smallest system in the AMPAC SWRO line. Built for small sailboats, powerboats, and liveaboard vessels where space and electrical load are both constrained. At 100 gallons per day, it supports 2 to 4 people at sea with standard daily consumption of 25 to 50 gallons per person – adequate for drinking, cooking, and personal hygiene. The low power draw makes it compatible with battery bank and solar configurations common on offshore sailing vessels. Footprint is compact enough for installation in an engine room or lazarette on boats 35 feet and above.

Nominal output: 100 GPD / 380 LPD

Contact AMPAC for application review, site-specific configuration, and formal quotation: (909) 548-4900.