Aurora Water advances evaluation of direct potable reuse; regional Northern Treatment Plant connection appears least costly

Aurora City officials and Aurora Water staff on May 21 discussed an ongoing evaluation of direct potable reuse, the process of treating reclaimed wastewater and delivering it directly to the drinking-water distribution system. Kevin Linder, Aurora Water’s Advanced Water Treatment Superintendent, said the city has operated indirect potable reuse since 2010 through the Prairie Waters project and is now studying DPR under Colorado’s newly issued Regulation 11.

The review is examining two primary connection options — a pipeline from Aurora’s Sand Creek reclamation facility and a shorter connection to Metro Water Recovery’s Northern Treatment Plant (NTP) — and the required enhanced source-water control, operation and outreach plans the state requires. “We want the water to be indistinguishable from all of our plants,” Linder said, describing Aurora’s standard of treating finished water so customers cannot tell its source.

Why it matters: Aurora’s master plan sets a PRA goal of diversifying supplies and reaching additional reuse capacity to increase drought resilience and system efficiency. DPR would reduce conveyance and stream losses tied to indirect reuse and could use existing advanced-treatment infrastructure at the Binney Water Purification Facility instead of building as many new radial wells.

Staff said the evaluation considered treatment schemes, sampling to establish pathogen and chemical log-removal values, enhanced source-water control staffing needs, capital and ongoing operation costs, and public outreach. Catherine Schumacher, an engineer on Aurora’s capital projects team and co-chair of the DPR task force, said the state regulation that enabled permit applications was finalized in 2023 and “uses Regulation 11” with two related policies staff refer to as Policy 15 and Policy 16. She outlined the project governance: a task force of subject-matter experts, a steering committee, and an executive board to advise strategy and budget.

On capacity and cost, staff framed near-term goals of roughly 5–10 MGD of DPR delivery by about 2030. Sand Creek’s current effluent capacity would allow only about 1.4 MGD for DPR in summer months because much of its flow is committed to nonpotable uses; a significant Sand Creek upgrade would cost on the order of tens of millions of dollars. By contrast, the NTP connection would supply more year-round flow with lower conveyance costs. “The punchline is when we did this number crunching, NTP still came out to be less expensive than the other options,” Linder said.

Staff said upgrades at Sand Creek to raise DPR capacity were estimated to start at roughly $25 million and could be larger given market conditions; staff also noted urban construction of a new pipeline to Sand Creek would be more disruptive than the shorter NTP tie-in. Staff estimated radial well capital and conveyance costs would make a no‑DPR, full-radial-well strategy expensive and physically challenging to achieve at the scale the master plan contemplates.

Enhanced source-water control is a major regulatory requirement for this project. Schumacher said Sand Creek’s sewer-shed contains about 1,200 significant industrial users while the NTP sewer-shed has about 400, and the difference affects how many additional pretreatment staff would be needed to maintain the stricter water-quality oversight the rule requires. Metro Water Recovery’s long-standing pretreatment program will be central to any NTP connection; staff are coordinating with Metro and the Colorado Department of Public Health and Environment (CDPHE) as the evaluation proceeds.

Shani Klein, Aurora’s deputy director for water internal and external communications, described outreach plans tied to the regulatory timeline. Colorado’s rule prescribes communications and testing prior to permit application; staff are planning public education, tours of the Binney facility, virtual materials, focus‑group testing of messaging and coordination with potential receiving utilities and municipal partners. “Most people don’t realize that they’re already getting potable reuse,” Klein said, urging outreach that explains both Prairie Waters history and new DPR safeguards.

Staff said next steps include roughly a year of required sampling for pathogen and chemical data; finalizing the enhanced source-water control plan and any intergovernmental agreements with Metro; continuing CDPHE coordination; developing the required operations plan and dashboards; and deciding whether to file a permit application, with a target in late 2026 if the city proceeds. No final policy decision or permit was made at the meeting.

Ending note: Staff framed DPR as a potential tool to add supply diversity, reduce stream losses and leverage existing advanced-treatment capacity but emphasized it requires continued technical validation, regulatory approvals and proactive public engagement before a permit would be sought.