As we implement water efficiency measures and assist tenants with their own water reduction strategies , metrics to track include total gallons of water consumed in aggregate Alternative Water Treatment ( AWT ) at Reagan National at each airport , water usage on a perpassenger basis , and given our access to Capital cost with installation for AWT = $ 750,000 water meter data , water usage on a pertenant basis , with a focus on those large
Annual operating costs for AWT = $ 61,000
consumers . Given the relatively low cost Annual water , sewer , and chemical savings = $ 77,000 of water , implementing cost-effective water reduction strategies must be Net estimated annual savings = $ 16,000 weighed against the economic cost of
Payback exceeds 40 years despite opportunity to save such initiatives . For example , as noted ,
4,000,000 gallons of water annually . our central utility plants are a significant consumer of water to heat and cool our facilities . Innovative advancements such as AWT technologies can be used to retrofit these facilities to drastically reduce water consumption by adjusting methods for maintaining water quality within the equipment . As shown in the text box , based on our analysis , while we could potentially reduce water use in the cooling towers at Reagan National by up to 4 million gallons of water per year , the return on investment would exceed 40 years which is well beyond our targeted investment criteria .
Best Practices Opportunities Building Green and Sustainable
When we build new facilities at our airports or undertake major renovations , we are committing to implement state-of-the-industry reduced consumption methodologies and working to ensure we are meeting or exceeding current best practices . Our Design Manual guides how we both build and to a lesser extent , operate our facilities and to what degree we are building with sustainability in mind . We are currently updating the Design Manual with sustainability as a focus . The intent is that our minimum standards for construction reflect the most recent efficiency standards for plumbing-related equipment and fixtures , irrigation requirements for landscaping and WaterSense appliance requirements for our tenants . In addition , below is a list of other potential activities we can consider reducing water consumption .
Monitor Water Use Over Time at the Meter Level to Identify Trends and Impacts of Water-Saving Measures
Water use can be broken down into various categories such as such as outdoor water consumption for irrigation , indoor water usage for bathrooms , kitchen and cooking facilities , and assorted cleaning applications , including rental car washing facilities . Submetering the various sources of water use is the first step in water conservation as we need to know who and how it is being used across our facilities . Submetering in the short term allows for leak identification whereas on a longer-term basis , it allows us to track trends and measure the progress of any efficiency measures we implement .
As noted , the Authority bills concessionaires and tenants for their water use which creates the opportunity to reach out to our biggest consumers of water to explore water reduction strategies . As indicated by in Table 9 , three of our top users of water at Dulles International account for 26 % of total water consumption . Currently , when there is a spike in water consumption , we will meet with tenants to determine if there is a leak of some sort , or if tenant usage patterns have changed . However , based on feedback from our concessionaire focus groups , there may be opportunities to provide more granular
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