Graywater

What is Graywater?

According to the CDPHE, graywater is a portion of the water used in a residential, commercial or industrial building that may be collected after the first use and put to a second beneficial use.  Regulation 86 outlines requirements, prohibitions, and standards for graywater use for nondrinking purposes.  Graywater sources may include water discharged from bathroom and laundry-room sinks, bathtubs, showers, and laundry machines. 

Colorado Law

The Colorado Department of Public Health and Environment (CDPHE) adopted Regulation No. 86 – Graywater Control Regulation, May 11, 2015, making graywater management an opt-in program, thus not mandatory, for local jurisdictions. To allow graywater use, local jurisdictions (e.g., a city or county) would have to adopt an ordinance or resolution to allow graywater use within their jurisdiction by developing a graywater control program that meets the requirements of Regulation 86.

Graywater use in Unincorporated Douglas County

After serious consideration of the regulatory requirements and potential public health and safety implications, environmental impacts and compliance issues, as well as associated costs, Douglas County has determined the organization will not adopt a Graywater Disposal Resolution.  General reasons for this decision include:

  • The primary focus is on protection of public health, safety and welfare.
  • The cost and resources necessary for putting such a program together, including program implementation (environmental permits and regulatory responsibility and liability).
  • The difficulty of properly enforcing such a program.

Specifically, graywater disposal may lead to some or all the following issues:

  • Unintended conflict with water rights for either a water provider or individual well users.
  • Exposure of people and pets to disease-causing pathogens.
  • Diminished sewage returns flow for the water and sanitation districts.
  • Reduced reclaimed water for municipal use.
  • Impacts on stormwater quality and runoff.
  • Can cause disease and or contamination if not filtered properly.
  • Design and implementation of some of these systems can be expensive initially. Soil types common in Douglas County would likely require an engineered design.
  • In colder climate regions, such as Douglas County, the soil may be unfit to use these systems during the colder months.
  • Graywater cannot be stored for more than 24-hours or it will begin to putrefy due to the organic solids in the water. Enforcement is difficult.
  • Graywater may contain fats, oils, grease, hair, urine, feces, blood, lint, soaps, cleansers, fabric softeners, and other harmful chemicals, which could be considered illicit discharges in some instances.
  • Even biodegradable soaps and detergents can present a problem over time when graywater is used for irrigation.
  • Most cleaning agents contain sodium salts which can create an alkaline condition and damage the soil structure.
  • Excess run-off could escape property boundaries and create problems for adjacent property owners (i.e., potential illicit discharge issues).
  • Can increase nitrogen and phosphorus levels in stormwater runoff, which are existing issues for the Cherry Creek and Chatfield watersheds, both of which are in Douglas County.