Water board recommends city opt out of graywater program, cites cost and public‑health concerns

The Water Resources Advisory Board recommended on Sept. 15 that the City Council adopt plumbing‑code language to opt the city out of establishing a local graywater regulatory program required by a new state law.

City staff said the change is required by a 2024 state law (identified in staff materials as “house bill 24 13 62”) that takes effect Jan. 1, 2026, and that local action is needed to avoid automatic allowance of graywater without a local regulatory framework. Crystal Mori, senior water resources engineer, told the board that "free water reuse is taking water from showers, bathrooms, sinks, and laundry machines, and reusing it in toilets or for underground irrigation on the same property." She said staff recommended opting out now because establishing and running a local graywater program would require new administrative, review, inspection and enforcement resources.

Why it matters: Staff estimated graywater could save up to 1% of citywide water demand if broadly adopted, but said actual homeowner and developer uptake has been low in other jurisdictions and in past trials. The board and staff said a local program would require plan review, inspections, backflow prevention, ongoing maintenance checks and tracking that the city currently lacks capacity to provide.

Board discussion and public comment focused on public‑health risks and on whether the proposed code would bar small, informal practices during droughts. Mark McIntyre, chair of the Planning Board, urged staff to consider unintended consequences for informal emergency uses — telling the board, "The way I read the code, this would be explicitly prohibited." Staff and the city attorney’s office said the draft code defines graywater as wastewater and would not apply to a resident temporarily capturing the warmup water from a shower in a bucket; staff said they would re‑review the proposed wording for clarity.

Staff noted a prior University of Colorado pilot was allowed under a research exemption, ran for a few years and was later discontinued because maintenance and research interest declined. Mori said the state’s change essentially flips a prior opt‑in approach (dating to the 2013 law) to an opt‑out, leaving Colorado cities to choose whether to create a local control program or to explicitly prohibit installation of graywater systems.

The board’s motion — recorded in the meeting as: "The Water Resources Advisory Board recommends that the City Council adopt the proposed graywater code changes in substantially the same form as Attachment A" — was moved, seconded and approved by the members present. Staff said the ordinance will go to City Council for first and second readings on Oct. 16 and Nov. 6, and that the state deadline for action is Jan. 1, 2026.

Staff emphasized the recommendation is not a permanent rejection of graywater: if future demand or technology changes, the city could revisit establishing a regulatory program. Several board members said they were open to future reconsideration if uptake or rebates make the strategy practical.

Ending: The board forwarded its recommendation to Council; Council consideration and the ordinance’s adoption schedule were outlined by staff. City staff proposed to return to boards with additional information if community interest or pilot programs change uptake expectations.