Scottsdale could face a 17% cut to its Colorado River water supply in 2027. City Council members spent a Tuesday, Oct. 20 study session weighing projects ranging from a new pump station to a purification plant estimated at up to $164 million.

The potential reduction hinges on a proposed Lower Basin agreement that has not been finalized. The Central Arizona Project (CAP), which delivers Colorado River water to the city, has characterized allocation numbers as provisional, according to ABC15.

Even under that scenario, Scottsdale would retain more CAP water than it delivered in 2025, according to the city's Thursday, Oct. 22 summary of the session. Staff said the city delivered about 82,600 acre-feet of drinking water in 2025.

Total deliveries including reclaimed water reached roughly 90,800 acre-feet. An acre-foot equals about 326,000 gallons.

No votes were taken. The study session produced directional support, not a funding decision. Axios Scottsdale reported the council did not take formal action, and it remains unclear when members might vote on a full advanced water purification facility.

The projects staff outlined will be included in upcoming funding appropriations for council consideration, the city said.

City Manager Greg Caton said the analysis was intended to give council a clearer understanding of costs and alternatives before moving forward. Caton told Axios the estimated cost of an advanced purification project grew partly because new state regulations changed the project's requirements, prompting a more detailed engineering study.

Two purification options without a proposed sixth pump-back station carried estimated capital costs of about $133 million and $164 million, with annual operating costs of $6.3 million and $7.3 million, according to the city. Axios reported the price tag could reach $261 million if the city adds a wastewater collection station in south Scottsdale.

Council members split on how aggressively to spend. Councilmember Solange Whitehead pushed for faster action on wastewater-to-drinking-water conversion. "We can't totally ignore cost," Councilmember Barry Graham said, according to Axios. Councilmember Jan Dubauskas said Scottsdale is not facing an immediate water shortage but acknowledged that water rates may go up, Axios reported.

The city did not estimate how the proposed projects would affect household water bills.

Staff also presented near-term options. One involves improving the distribution system's ability to move Salt River Project water from the Chaparral Water Treatment Plant into central and northern Scottsdale during summer.

The city is also pursuing water recovery from city-owned land in the Harquahala Valley. A proposed sixth wastewater pump-back station near Indian Bend and Hayden roads could return 4 million gallons per day to the Scottsdale Water Campus for treatment and reuse.

About 75% of Scottsdale Water customers now have advanced meters that provide hourly usage data through the city's WaterSmart portal. Staff reviewed conservation programs including irrigation rebates, grass removal incentives and leak detection assistance.

Public engagement on an updated drought management plan is planned for this winter, with the updated plan expected before council for approval in spring 2027. Scottsdale remains in Stage 1 of its current drought plan.