Data centers are expressly allowed as a principal use only in the M-2 General Industrial District; a proposed data center in another district requires a zoning-map amendment or rezoning. Data Centers

Rezoning requires review and a public hearing by the Planning and Zoning Commission and a separate public hearing before the Board of Supervisors. Notice must be published 4 to 20 days before each hearing, and nearby property owners must receive written notice; the Commission generally has 30 days after its hearing to report its recommendation. No such amendment shall be made without a report

Before construction, reconstruction, structural enlargement, increased floor area, or a change in use, the applicant must obtain a Construction Compliance Certificate and submit plans and other information demonstrating compliance; applicable fees may be charged. a Construction Compliance Certificate shall be required prior to initiation of any construction or development within any district

A zoning permit expires if construction has not begun within six months or has not been completed within two years, although the Zoning Administrator may grant an extension of up to six months.

Commercial and industrial development requires site-plan review addressing structures, utilities, roads, drainage, water and sewage systems, parking, flood hazards, slopes, buffering, and related matters, with review by the Zoning Administrator, County Engineer, County Health Officer, and the Planning and Zoning Commission and/or Board of Adjustment. A site plan review is required

In the M-2 District, buildings may cover no more than 50 percent of the lot and generally must have setbacks of 20 feet front, 20 feet rear, 15 feet side, and 20 feet from a street-side lot line; the maximum height is 60 feet, and adjoining yards must be at least 25 feet where the property borders an agricultural or residential district. Minimum required front, side and rear yards and maximum height

M-2 sites must be large enough to meet setback, parking, loading, buffering, sewage, and other space requirements. Where public or community sanitary sewer is unavailable, the site must be at least one acre and at least 125 feet wide. The minimum total lot area shall be the area necessary

M-2 operations may not store outside raw, finished, or waste products that could create adverse dust or odors, may not allow junk or debris to accumulate, and may be required to screen storage yards. Lighting must be directed to avoid shining onto adjacent residential property and to prevent light pollution.

Data centers must provide off-street parking under the applicable or similar-use standards because no specific data-center parking standard is assigned. Buildings of at least 6,000 square feet requiring vehicle deliveries must also provide off-street loading space, generally including at least one 12-by-40-foot loading stall plus additional stalls based on floor area. In the case of any building

Development in the Bluffland Protection Overlay District requires additional review. Construction, grading, earth moving, or vegetation removal outside a Bluff Impact Zone requires Planning and Zoning Commission approval, while such activity inside a Bluff Impact Zone requires a Conditional Use Permit. Structures are prohibited in Bluff Impact Zones, and structures in the overlay are limited to 35 feet in height. All development is subject to the Bluffland Protection Overlay District

Within designated Public Water Well Overlay protection zones, industrial or animal wastewater lagoons within 1,000 feet, landfills, junkyards, gas stations, toxic or hazardous-waste facilities, bulk chemical facilities, and uses requiring or storing hazardous or toxic materials other than household uses are prohibited. Prohibited Uses – Zones 1 & 2

A project within 10,000 linear feet of the Decorah Municipal Airport runway centerline may be subject to Airport Overlay Zone requirements, including an airport-related permit, height restrictions, review of structures and utilities, lighting and glare controls, and possible avigation-easement requirements. All development is subject to the Bluffland Protection Overlay District

Any data-center development in a designated floodplain requires a Floodplain Development Permit before construction or other development, including filling, grading, paving, excavation, or equipment storage. New or substantially improved structures generally must be elevated at least one foot above the base-flood elevation or meet specified floodproofing requirements. A Floodplain Development Permit issued by the Administrator shall be secured prior to any floodplain development

Data centers are expressly allowed as a principal use in the M-2 General Industrial District, so they do not require a conditional-use permit solely because they are data centers, subject to applicable zoning and overlay requirements. Data Centers

M-2 zoning allows up to 50% building coverage, permits a minimum one-acre lot where public or community sewer is unavailable, and provides defined setbacks of 20 feet front and rear, 15 feet side, and 20 feet on a corner street side; no side or rear setback is required where the property adjoins a railroad. Minimum Bulk Requirements

M-2 permits buildings up to 60 feet high, subject to applicable airport, bluffland, floodplain, and other overlay restrictions. Maximum height 60 feet

Because M-2 incorporates the principal uses permitted in the M-1 district, it allows public utilities, including utility storage buildings and enclosed storage yards, which can support data-center infrastructure. Public utilities including storage buildings and enclosed storage yards

A lawfully operating data center that later becomes inconsistent with a zoning amendment may continue as a nonconforming use until removed, although it generally may not be enlarged or increased and may lose that status after specified discontinuance, destruction, or removal thresholds. Nonconformities may continue

A personal solar energy system is an accessory use to a permitted principal use in any zoning district, allowing an eligible data-center site to install on-site solar generation; ground-mounted systems require a building permit and must meet height and setback limits. considered an accessory use to a principal permitted use in any zoning district

Community solar and solar-farm systems are allowed in the M-2 district through a conditional-use permit, subject to siting, screening, fencing, stormwater, decommissioning, and bonding requirements. allowed by Conditional Use Permit in zoning districts A-1, A-2, C-1, C-2, M-1, M-2

A personal small wind energy system is an accessory use to a permitted principal use in any zoning district, allowing qualifying on-site wind generation; it requires a building permit, must be below 100 kW, and must meet setback, noise, lighting, and other requirements. considered an accessory use to a principal permitted use in any zoning district

Personal large and commercial wind energy systems are available in the M-2 district through conditional-use permits, subject to setback, noise, safety, road-use, decommissioning, and financial-assurance requirements. allowed by Conditional Use Permit in zoning districts A-1, A-2, C-1, C-2, M-1, M-2