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Increase Water Use Efficiency

Water conservation is the practice of purchasing , operating , and maintaining water system equipment and controls to use water only as needed ; to capture and reuse water where viable ; and minimize the loss of water through evaporation , leaks , and smart controls . As we implement additional sustainable water efficiency measures , we would expect to see a reduction in water consumption over time on a perpassenger basis .

Baseline

In 2019 , Dulles International and Reagan National operations used approximately 297 million and 185 million gallons of water , respectively . This equates to approximately 12 gallons per passenger at Dulles International and 7.8 gallons per passenger at Reagan National . Based on projected passenger growth at both airports , assuming no change in the per-passenger ratios , by 2035 Dulles International will be consuming 446 million gallons of water per year whereas Reagan National will be consuming 250 million gallons of water . The primary consumers of water at both airports are our chiller plants , third-party commercial food preparation kitchens , and rental car companies .

The Authority supplies water to airport tenants , concessionaires , and other end-users at our airports and we bill them accordingly . With sufficient metering in place , large water processes can be identified , and we can target our efforts where the potential impact is the highest . Based on submetering data ⁴⁰ available from Dulles International and summarized below in Table 9 , as expected , our cooling tower make-up water is the primary source of water consumption , representing 12 % of all water consumed in 2018 . Based on an analysis done at Reagan National , it is unlikely we can economically reduce the amount of cooling tower make-up water we use at Dulles International . However , there may be opportunities elsewhere . For example , food preparation companies use 8 % of all water consumed at Dulles International and our rental car partners consume an additional 6 % of the airport ’ s water . The results are comparable at Reagan National airport as well .

Metrics to Measure Success

Table 9 : Dulles International Water Consumption 2018

Rental cars 17,303,980 6 %

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2018 Dulles International water metering data provided by Metropolitan Washington Airports Authority ( 2019 data pending ).

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