Unlisted uses are prohibited. Because data centers are not specifically listed, a data center requires a formal determination that it is substantially similar to a permitted use and compatible with the zoning district and General Plan, or a zoning ordinance amendment; otherwise, it cannot be established.

All land, buildings, and structures must be used in strict compliance with the Zoning Ordinance and all conditions attached to County permits.

Depending on its classification and zoning district, a data center may require planning clearance, a special permit, Architecture and Site Approval, or a discretionary use permit combined with Architecture and Site Approval. If classified as a major utility or public facility, it requires discretionary approvals where that classification is allowed.

Discretionary applications generally require a public hearing and public notice at least 10 days before the hearing, including mailed notice to property owners within 300 feet or, if fewer, to at least the 24 closest properties, plus newspaper publication unless an exception applies.

Discretionary permits are subject to CEQA unless exempt. If an environmental assessment is required, the applicant must pay for it, the hearing generally cannot be scheduled until it is completed, and the permit cannot be approved until the environmental document is approved or certified.

Discretionary approval requires findings regarding General Plan and zoning consistency, site adequacy, neighborhood compatibility, traffic, parking and loading, emergency access, water quality and wastewater, noise, erosion, and storm drainage. If the required findings cannot be made, the application must be denied.

Commercial, industrial, office, and other nonresidential development must provide required off-street parking. Buildings of at least 10,000 square feet that receive or distribute materials by truck must provide at least one off-street loading space, plus one additional loading space for each additional 20,000 square feet; major-utility parking is set through the use-permit process.

Properties in combining districts are subject to additional or superseding restrictions, including possible limits involving lot size, setbacks, design review, scenic-road buffers, historic resources, wetlands, housing sites, and Coyote Valley development.

Within a city's urban service area, applications for specified approvals, including use permits and Architecture and Site Approval, generally require an official determination of city General Plan conformance.

Certain vacant parcels within a city's urban service area cannot receive applications for Architecture and Site Approval, use permits, zone changes, or construction of commercial or industrial buildings unless annexation has been initiated and denied or the city provides a written waiver. Specified exceptions apply.

Applications require filing fees, and the County will not process them until the required fees are paid in full. Correcting a zoning violation also requires a separate land-use violation fee.

A permitted use or approved structure generally must be established within four years, or within five years when authorized by a use permit. One extension of up to two additional years may be granted if requested before expiration.

A use operating under Architecture and Site Approval or a use permit is generally considered abandoned or revoked if it ceases for 12 consecutive months, unless an express condition provides otherwise.

A legally existing data center that becomes nonconforming may not be intensified or expanded in area or volume. Its nonconforming status terminates after at least 12 consecutive months of cessation, and reconstruction after destruction exceeding 75 percent of construction valuation generally ends the right to continue the nonconforming use, subject to specified exceptions.

Violations may result in citations, recorded zoning-violation notices, abatement actions, criminal infractions or misdemeanors, daily penalties, and civil recovery of enforcement and related costs.

An unlisted data-center use may be approved through an interpretation application if the Zoning Administrator finds it substantially similar in nature and intensity to a listed permitted use and compatible with the zoning district and General Plan. A discretionary permit may still be required if impacts exceed those of the comparable use.

Data-center functions may potentially qualify under the Broadcasting classification, which includes electronic communication facilities and telephone switching centers. In the ML and MH industrial districts, this requires a use permit and Architecture and Site Approval.

A data center classified as an office may use the established office-use category in the CN, CG, OA, ML, and MH districts, subject to Architecture and Site Approval.

Data centers or related facilities that qualify as manufacturing, warehousing, storage, distribution, or office uses may locate in the ML and MH industrial districts, subject to the applicable review requirements.

Associated substations and other qualifying utility or public-facility infrastructure may be permitted in commercial and industrial districts. Minor facilities require Architecture and Site Approval, while major facilities require a use permit and Architecture and Site Approval.

In the San Martin Industrial Use Permit Area, new or significantly expanded light-industrial uses not otherwise allowed by the base district may be approved with a use permit and Architecture and Site Approval, subject to the San Martin Integrated Design Plan and applicable General Plan policies and excluding specified uses such as intensive manufacturing and petroleum-products distribution.

For projects subject to Architecture and Site Approval in commercial or industrial districts, the Zoning Administrator may modify setback and height limits when justified by design quality, compatibility, buffering, or the purposes of the approval.

In the ML and MH industrial districts, setbacks generally apply only when a property is adjacent to or across a street from a residential district, unless Architecture and Site Approval imposes a setback. Maximum building height is generally 65 feet, with lot coverage limits of 40 percent in ML and 50 percent in MH.

Minor expansions or modifications of an authorized use or building may receive administrative Architecture and Site Approval without a public hearing if they add no more than 2,000 square feet, are no more than 35 feet high, require no environmental assessment, add fewer than six parking spaces, require no designated-heritage-tree removal, and need no significant site improvements.

The County may combine concurrently required discretionary permits and use the highest approval authority as the sole approval authority, avoiding separate decision processes for each permit.

Required parking may be reduced for a use subject to discretionary review when the site cannot reasonably accommodate the requirement, is near public transit, has unusually low automobile demand, or has a uniquely different use design. A qualified parking or transportation study may be required.

Multiple uses may share or cooperatively provide required parking when their peak parking demands occur at different times, subject to a qualified parking study, acceptable legal agreements, and County approval.

A development agreement may allow an approved project to proceed under specified existing policies, rules, regulations, and conditions, providing greater certainty against later changes. It may also secure public improvements such as streets, transportation, water, sewer, and utility facilities, but must be consistent with the General Plan, applicable specific plans, and the Zoning Ordinance and be approved by the Board of Supervisors.

A lawfully established data-center use that later becomes nonconforming may continue operating and may be changed to a similar use that is less intense and less impactful. It generally may not be intensified or expanded, and its nonconforming status ends after at least 12 consecutive months of cessation.

Approved structures and uses generally have four years to be established, while uses approved by a use permit generally have five years. One extension of up to two additional years may be granted if requested before the deadline and supported by the required application and fee.

The County must notify an applicant within 30 days whether a permit application is complete or identify missing information. An applicant may appeal an incompleteness determination to the Planning Commission, which must decide the appeal within 60 days.

Government-agency utility structures and facilities may be exempted from local zoning regulations by the Board of Supervisors, and federal or state law may independently exempt certain utilities. This exemption does not automatically apply to privately operated data centers.

Lot line adjustments between four or fewer adjoining legal parcels may facilitate site reconfiguration or expansion without creating additional parcels. The adjustment remains subject to state law, the General Plan, zoning, building regulations, and other applicable requirements, and is generally decided administratively by the planning director.

A special permit provides a discretionary approval path for uses presumed to be generally appropriate and compatible within a zoning district and generally lesser in intensity and impact than uses requiring a use permit, where the ordinance makes it applicable.

A variance may provide relief from development standards such as setbacks when unique substantial and detrimental property circumstances would otherwise preclude reasonable use, but it cannot authorize a use that zoning regulations do not otherwise allow.

The planning director may exempt pending applications, in whole or in part, from newly enacted zoning provisions in specified circumstances, including applications deemed complete before the new provisions take effect and certain substantially complete building permit applications.

A private party may initiate a zoning amendment application to seek changes to zoning text or the zoning map, subject to Planning Commission recommendation, Board of Supervisors approval, state law, and consistency with the General Plan and ordinance purposes.