Los Angeles County prohibition on data centers in unincorporated areas (2026)

LOS ANGELES COUNTY, Calif. — IMMEDIATE PROHIBITION ON LARGE-SCALE AI DATA CENTER DEVELOPMENT IN UNINCORPORATED AREAS, ordered by DEPARTMENT OF REGIONAL PLANNING DIRECTOR AMY BODEK by MEMORANDUM on THURSDAY, SEPTEMBER 17, 2026. THE INSTRUMENT IS ADMINISTRATIVE, NOT LEGISLATIVE, AND THAT IS THE FIRST THING TO UNDERSTAND ABOUT IT. This is a departmental directive expressly framed as INTERIM GUIDANCE FOR PLANNING STAFF, issued while the county 'moves toward codifying the prohibition' in the zoning code. It is not an interim urgency ordinance under Cal. Gov. Code § 65858 (no 45-day term, no four-fifths board vote reported), and it is not itself a zoning amendment. Its operative force therefore rests on the planning department's discretion over application processing rather than on an enacted prohibition, which makes it FAST AND IMMEDIATE BUT MORE EXPOSED than an ordinance to a challenge by an applicant arguing the department cannot refuse to process a use the code permits. NO EXPIRY IS STATED — unlike a § 65858 moratorium it does not self-terminate, but it is also expressly transitional. PROCEDURAL SPINE: (1) APRIL 2026 — Board Chair and First District Supervisor HILDA SOLIS introduced a motion addressing public health and environmental concerns surrounding data centers; THE BOARD OF SUPERVISORS APPROVED IT UNANIMOUSLY. (2) The county's REPORT BACK on that motion IDENTIFIED ZONING CHANGES THAT WOULD PROHIBIT THESE FACILITIES. (3) SEPTEMBER 17, 2026 — the Bodek memorandum implements that conclusion immediately as staff guidance. (4) Solis states she 'intends to bring additional actions before the Board of Supervisors to implement recommendations from the departments of REGIONAL PLANNING AND PUBLIC HEALTH to amend the county's zoning code and prohibit data centers pow[ered by AI].' THE ENDPOINT IS A PROHIBITION, NOT A PAUSE, which distinguishes this from the entire moratorium cohort and places it with Irwindale CA data center ban ordinance (2026), Monterey Park Data Center Ban (Measure NDC) and Poway CA AI data center ban ordinance, first reading (2026) — but at county scale. THE INVOLVEMENT OF THE DEPARTMENT OF PUBLIC HEALTH IS UNUSUAL AND WORTH NOTING: almost every measure in this dataset is produced by planning staff alone, and a public-health department co-authoring data center siting recommendations is a materially different evidentiary posture for defending a health-based prohibition. TWO STATED RATIONALES, Solis quoted: (a) LOCAL — 'I introduced it in response to concerns raised by SAN GABRIEL VALLEY RESIDENTS who were understandably concerned about the effects of data centers in their communities, concerns that have since been reflected nationwide'; (b) EXISTENTIAL — 'The need for such a ban has only been further underscored by ALARMING DEVELOPMENTS FROM THE AI SECTOR ON CATASTROPHIC IMPACTS THE TECHNOLOGY MAY HAVE ON HUMANITY.' RATIONALE (b) IS THE SECOND INSTANCE IN THIS DATASET of a United States local government resting a land-use restriction partly on AI existential risk rather than local impact; the first is Gary IN mayoral executive order data center moratorium (2026). THE DIFFERENCE MATTERS LEGALLY: Gary's executive order rests on that rationale alone, which is why that entry flags ultra vires and pretext exposure. LOS ANGELES COUNTY PAIRS IT WITH A DOCUMENTED PUBLIC-HEALTH AND ENVIRONMENTAL RECORD produced by two county departments, so the existential-risk language is supplementary rather than load-bearing and does not carry the same vulnerability. THE SAN GABRIEL VALLEY ORIGIN TIES THIS TO AN ALREADY-DENSE CLUSTER: Monterey Park Data Center Ban (Measure NDC) (voters approved MEASURE NDC in June 2026 amending the land use element to prohibit all data centers unless repealed by future voters — the source calls it the first of its kind in California, preceded by a 45-day moratorium later extended while staff codified an outright ban), Irwindale CA data center ban ordinance (2026), Commerce CA 45-day data center urgency ordinance (2026), plus unindexed El Monte and Alhambra. THE TRIGGERING PROJECT, recorded: SDCF MONTEREY PARK, LLC proposed demolishing vacant commercial buildings at 1977 SATURN ST. and constructing a 218,400-SQUARE-FOOT single-storey data center on 15.8 ACRES; residents raised air, land and water pollution concerns. ALSO RECORDED: the City Council of neighbouring INDUSTRY unanimously approved a zoning change in February allowing construction of a battery storage site (unindexed, and an enabling rather than protective action). THE APPLICABILITY THRESHOLD FOR 'LARGE-SCALE' IS NOT STATED IN THE SOURCE.