Subd. 1. Reasonableness.

Standards of the commissioner defining airport hazard areas and the categories of uses permitted and airport zoning regulations adopted under sections 360.011 to 360.076, shall be reasonable, and none shall impose a requirement or restriction which is not reasonably necessary to effectuate the purposes of sections 360.011 to 360.076. In determining what minimum airport zoning regulations may be adopted, the commissioner and a local airport zoning authority shall consider, among other things, the character of the flying operations expected to be conducted at the airport, the location of the airport, the nature of the terrain within the airport hazard area, the existing land uses and character of the neighborhood around the airport, the uses to which the property to be zoned are planned and adaptable, and the social and economic costs of restricting land uses versus the benefits derived from a strict application of the standards of the commissioner.

Subd. 1a. Protection of existing neighborhoods.

1. (a) In order to ensure the minimum disruption of existing land uses, particularly established residential neighborhoods in built up urban areas, the airport zoning standards of the commissioner and the local airport zoning ordinances or regulations adopted under sections 360.061 to 360.074 shall distinguish between the creation or establishment of a use and the elimination of an existing use, and shall avoid the elimination, removal, or reclassification of existing uses to the extent consistent with reasonable standards of safety. The standards of the commissioner shall include criteria for determining when an existing land use may constitute an airport hazard so severe that considerations of public safety outweigh the public interest in preventing disruption to that land use.
2. (b) No airport zoning standards or local airport zoning ordinances or regulations shall be adopted pursuant to sections 360.061 to 360.074 that classify as a nonconforming use or require such classification with respect to any low-density residential structure or isolated low-density residential building lots existing on January 1, 1978 in an established residential neighborhood.
3. (c) A local airport zoning authority may classify a land use described in clause (b) as an airport hazard if that authority finds that this classification is justified by considerations of public safety and is consistent with the airport zoning standards of the commissioner. Any land use described in clause (b) which is classified as an airport hazard shall be acquired, altered or removed at public expense.
4. (d) The provisions of this subdivision shall not be construed to affect the classification of any land use under any zoning ordinances or regulations not adopted pursuant to sections 360.061 to 360.074.

Subd. 1b. Amendment of standards.

Within nine months after March 29, 1978, the commissioner shall amend the standards defining airport hazard areas and categories of uses permitted therein to conform with the requirements of Laws 1978, Chapter 654. Until the commissioner adopts amended standards as required by this subdivision the unamended standards, insofar as they require classification of any residential property as a nonconforming use contrary to the provisions of subdivision 1a, clause (b), shall be without force or effect.

Subd. 2. Nonconforming uses.

No airport zoning regulations adopted under sections 360.011 to 360.076, shall require the removal, lowering, or other change or alteration of any structure or tree not conforming to the regulations when adopted or amended, or otherwise interfere with the continuance of any nonconforming use, except as provided in section 360.067.