Gray Water Treatment and Reuse System (G-WTRS)

Published April 22, 2020

Convoy resupply and removal of water to military personnel and emergency responders working in expeditionary settings is burdensome with respect to cost, logistics, and security. The G-WTRS will support water sustainment needs by recycling water for critical hygiene activities such as showering, laundering, and hand-washing.


The G-WTRS is a containerized system for water reuse in hygiene facilities at temporary bases supporting up to 1000 personnel. It fits in a 20' ISO shipping container and can treat up to 30,000 gallons per day (gpd) of gray water generated from field shower and laundry systems. The G-WTRS uses a patented enhanced pretreatment biofilter to reduce membrane fouling, and it consumes 50% less energy than conventional tactical water purification systems. The G-WTRS can recover 80% of the water for reuse in showering and laundry, as well as 10% for reuse in latrines.

Requirements for Running the System

  • Power (4-10 kW, depending on flow rate);
  • O&M (6 hrs for setup and 1 hr/week for maintenance/monitoring);
  • Consumable materials (Food grade table salt: 40 lbs/month; Coagulant: 1 gal/month; Membrane cleaning solution: 2 gal/month);
  • Storage tanks or bladders for gray water, product water, and wastewater (can be provided);
  • Deployable shower and/or laundry systems (containers/trailers) with accessible plumbing (above ground).


ERDC demonstrated the Gray Water Treatment and Reuse System (G-WTRS) in an operational training area at Fort Leonard Wood. The G-WTRS will be tested for several months at a time using Soldier-generated gray water from shower and laundry systems. The resulting data supported a successful Health Risk Analysis by Army Public Health Center, which concluded that using the water recycling system as demonstrated represents no additional health risk compared to using potable water for showering and laundry.


  • Development: Army S&T (Assistant Secretary of the Army for Acquisition, Logistics, and Technology, FY13-16)
  • Demonstration: National Defense Center for Energy and Environment (NDCEE, FY 17-19)


Technical Readiness Level 6 (Performance validated in a relevant environment). Additional funding is required for final prototyping and implementation.

Contact Updated 25 August 2020

Dr. Martin Page
(217) 373-4541

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