Background

The Colorado Water Plan (2015) sets a goal to achieve 400,000 acre-feet of conservation in the municipal and industrial sectors by 2050. Further, the Fort Collins Utilities Water Efficiency Plan (2015) sets a goal to reduce average water use to 130 gallons per capita per day by 2030. This requires an additional 8% reduction from the current 5-year average over the next 8 years. Both plans suggest exploring graywater as a potential strategy to reduce water use. 

Also, City Plan (2019) points to encouraging greater efficiency in new and redevelopment. Fort Collins is expected to grow significantly, with a potential for 30,000 new dwelling units in the Growth Management Area (GMA). Thirty percent are expected to be single-family dwelling units and about 80 percent of all additional dwelling units are expected to be outside of the Fort Collins Utilities water service area. An estimate from Denver Water when the agency adopted its ordinance in 2016, suggests that for every 1,000 graywater systems installed in new single-family homes, enough water could be saved to serve about 125 household per year. More empirical research and data based on real-world behavior is needed to understand if this estimate is realistic and can be relied on for water resource planning.  

Graywater also relates to the larger context of exploring tactics to use water more sustainably. While much of the water used by Fort Collins residents is treated to drinking water standards, not all of it needs to be. The City has already implemented raw (untreated) water for park irrigation and the state allows limited rain barrel use. Graywater is potentially another area where water treated to drinking water standards is not required.