Jump to main content.


Top 10 Water Management Techniques

EPA's Sustainable Facilities Practices Branch developed the following list of top 10 water management techniques that have proven helpful in managing water use at facilities throughout the Agency.

  1. Meter/Measure/Manage
  2. Optimize Cooling Tower
  3. Upgrade Sanitary Fixtures (High-Efficiency Toilets and Urinals, Faucet Aerators)
  4. Eliminate Single-Pass Cooling
  5. Incorporate Landscape Irrigation/Xeriscaping
  6. Reduce Steam Sterilizer Tempering Water Use
  7. Reuse Culture Water
  8. Control Reverse Osmosis System Operation
  9. Recover Rooftop Rainwater
  10. Recover Air Handler Condensate
1. Meter/Measure/Manage

The process of metering, measuring, and managing laboratory facilities is essential for effective water management. Metering and measuring help in analyzing a facility's water usage, and proper management of mechanical equipment results in greater water efficiency. Making sure that the equipment is run correctly and maintained properly is the key to preventing excess water usage through leaks and malfunctioning mechanical equipment.

2. Optimize Cooling Tower

Cooling towers provide a vital source of cooling for laboratories, but they are also large consumers of water. Cooling tower operations can be optimized by carefully controlling the ratio of the quantity of water evaporated to the quantity of water discharged (blowdown). The quantity of water evaporated is a function of the cooling demand. The quantity of blowdown should be controlled using an automated conductivity controller, and by maintaining proper cooling tower water chemistry. The ratio of evaporation to blowdown is called the cycles of concentration. If possible, cooling towers should be operated at six or more cycles of concentration for maximum water-efficiency. In addition, metering the quantity of water put into and discharged from the cooling tower provides information that helps to better manage the efficiency of the tower.

3. Upgrade Sanitary Fixtures (Waterless Urinals, Low-Flow Toilets, Faucet Flow Control)

Prior to the 1990s, when the government established federal water-efficiency standards, most EPA facilities were outfitted with inefficient sanitary fixtures, such as toilets that used 3.5 gallons per flush (gpf). Several EPA laboratories have since received water-efficiency upgrades, including new toilets with efficient flow rates of 1.6 gpf, urinals with 1.0 gpf rates or below, and even waterless urinals in some men’s bathrooms. If you have old sanitary fixtures, consider an upgrade. In addition, many lavatory faucets that flow at 2.0 gpm or more can be retrofitted with spout-end flow control devices that limit flow to 0.5 gpm. These devices provide a comfortable spray for washing and rinsing hands, and they save a significant amount of water.  

4. Eliminate Single-Pass Cooling

Single-pass cooling uses a continuous flow of water that is circulated once through the system for cooling purposes and is then disposed of down the drain.

5. Incorporate Landscape Irrigation/Xeriscaping

Xeriscaping is a type of landscaping that conserves water by planting native, water-efficient plants rather than water-intensive ones, and utilizes techniques that minimize the need for irrigation. A laboratory can significantly reduce its total water consumption by incorporating xeriscaping techniques, which will help lower or eliminate the demand for irrigation water. Within an existing landscape, irrigation water use can be reduced by 10 to 20 percent by having an irrigation water audit performed (seek out irrigation professionals that are WaterSense®  partners) and using a weather-based irrigation controller or soil moisture sensor to control landscape irrigation.

6. Control Steam Sterilizer Water

Steam sterilizers use cooling water to temper steam condensate discharge from the sterilizer to the laboratory drain. Many older sterilizers discharge a continuous flow of tempering water to the drain, even when it is not needed. This can be prevented with improved operational controls, or by retrofitting the sterilizer with a tempering water control kit.

7. Reuse Culture Water

Several EPA laboratories require water for aquatic culture research. In some cases, culture water is pumped into laboratory specimen tanks from local bodies of water, such as lakes or bays, but then might be discharged into the sewer after use.

8. Control Reverse Osmosis System Operation

Up to 10 percent of a laboratory’s water consumption can be related to the multi-step process of generating deionized (DI) water through reverse osmosis (RO). Water savings can be achieved by carefully regulating DI generation rates to meet laboratory demand. Avoid producing excess DI water that overflows to drains.

9. Recover Rooftop Rainwater

Rooftop recovery systems capture rainwater from the roof and redirect it to a storage tank. This cache of water can then be used for various purposes throughout the facility, such as flushing toilets, supplying cooling towers, and irrigating the landscape.

The Region 7 Science and Technology Center in Kansas City, Kansas, has incorporated a state-of-the-art rooftop rainwater recovery system in its new facility. The design consists of a 1,500-gallon underground settling tank and a 10,000-gallon holding tank. This system has the potential to save the laboratory more than 500,000 gallons of water per year.

10. Recover Air Handler Condensate

The normal operation of air conditioning equipment in warm, humid climates produces condensate water from the cooling coils. Rather than draining this water into the sewer system, some EPA laboratories are capturing this water for use in cooling towers and other various applications.

For more information on water saving best practices, please see the resources available from the Federal Energy Management Program (FEMP).


Local Navigation


Jump to main content.