Mesa council delays vote on text amendment tied to battery storage project under construction

Mesa City Council members at their Sept. 22 study session debated a proposed citywide zoning text amendment that staff said would both revise rules for legal nonconforming uses citywide and create a limited procedure to treat some already-permitted projects as procedurally conforming; councilmembers requested more briefings and indicated they would continue the item to the Oct. 6 study session for fuller review.

City staff told the council the change was prompted by a unique situation: a battery energy storage facility that received planning permits and has active construction, but which a subsequent zoning administratorinterpretation suggested the use might not be permitted under a strict reading of the code. Staff said the proposed ordinance would clarify that projects already permitted and under construction could be treated as procedurally conforming for the narrow purpose of allowing completion and financing, while adding a broader rewrite of the nonconforming chapter to reduce hurdles for some improvements to older buildings.

A city staff member described the effect this way: "We we're cleaning up a partial mess of our own making, and the way that the city had handled the approval of this, but it we did approve it. We gave them the green light to move ahead with it, and then there were some challenges about how that had been implied. And so, out of fairness to them, this was to allow them to complete the financing." The staff speaker said the change would allow the under-construction site to finish financing but would prohibit expansion without returning to the city for approvals.

Council members raised several concerns: whether the amendment improperly benefits a single developer, the adequacy of safety review for battery energy storage systems (some members noted the intensity of potential fire incidents), and the implications of making a citywide code change in response to one project. Council members asked for briefings from fire, building-safety and energy-resources staff and requested more detail on how the proposed changes would affect other uses such as single-family nonconforming residences and data centers.

Staff said a broader battery storage ordinance is planned for late November or December that will address many safety, siting and permitting issues. Staff also said two battery storage developments could be affected but that the current text amendment was drafted primarily to resolve the status of the one project already under construction, which staff said was under contract with SRP and had active construction near Fire Station 219.

Multiple council members said they had not been adequately briefed prior to the meeting and asked for a two-week continuation. The council directed staff to brief all councilmembers and scheduled the item for further discussion at the Oct. 6 study session; at the study session no final vote on the ordinance was recorded.

The discussion underscores competing priorities for the council: protecting public safety through careful code change and public outreach, while avoiding retroactive penalties that could derail an in-progress project and its financing.