Any use, building, or structure legally existing at the time of the enactment of this title which does not conform with the requirements of the zoning district in which it is located, shall be deemed to be legally nonconforming and may be continued except as hereinafter specified.

Nonresidential buildings or uses which legally exist on the effective date of the ordinance codified in this title and which are not in conformity with the provisions of this title, shall be declared to be nonconforming and therefore, detrimental to the orderly development of the City.

Nonconforming buildings and uses shall be brought into conformity or eliminated as quickly as possible, consistent with the rights of the owners and users thereof, for the purpose of promoting the public health, safety, comfort, convenience, prosperity, and general welfare.

To avoid undue hardship, nothing in this title shall be deemed to require a change in the plans, construction, or designated use of any building on which actual construction was lawfully begun prior to the effective date of the ordinance codified in this title or amendment hereto.

This section shall not apply to any use, building, or structure established in violation of the previously adopted zoning ordinance for the City, unless such use, building, or structure presently conforms with the provisions of this title.

Unless a variance is approved, any physical addition, alteration, expansion or extension to an existing legal nonconforming structure shall comply with the regulations of the zoning district in which it is located.

Whenever a nonconforming use of a building or lot is discontinued for a period of six months, except pursuant to a valid order of a court of competent jurisdiction, such a use shall be considered to be abandoned. Any subsequent use of the building or lot shall conform to the regulations of the zoning district in which the building or lot is located.

A nonconforming use shall not be moved, enlarged, extended or expanded within the structure it occupies, nor expanded so as to occupy a greater area of land, than was occupied by such use at the time this title was adopted or amended.

With the exception of residential structures containing less than five units, a conditional use permit and, if necessary, a variance, shall be secured prior to any structural alteration, enlargement, extension, expansion or substantial rehabilitation of a nonconforming structure.

Provided that no structural alterations are made to the building or lot, a nonconforming use shall not be changed to another nonconforming use unless the City Planning Commission determines, through the conditional use permit process, that the new use is similar in nature, or more restrictive than, the previous use.

A nonconforming structure which is damaged by fire, flood, or other casualty or act of God to an extent exceeding 50 percent of its previous value, as presented in a certified appraisal, shall not be restored or reconstructed except in conformance with the regulations of the zoning district in which it is located.

Ordinary nonstructural repairs, alterations, or maintenance shall be permitted to be made to a nonconforming structure in order to keep said structure in sound condition.

Alterations or repairs of a structural nature may be made to a nonconforming structure only when such improvements will not exceed 25 percent of the current value of the building, as presented in a certified appraisal unless such alteration or repairs are approved under the provisions of a conditional use permit as provided in subsection (D) of this section.

Nothing in this chapter shall be interpreted as preventing the use of any substandard parcel of land or lot, which was legally existing as of the effective date of the ordinance codified in this title or amendments hereto, subject to compliance with the regulations of the zoning district in which said parcel or lot is located.

The City may require the merger or combining of a substandard lot or lots with a contiguous lot or lots under common ownership as a condition of allowing a new use or new construction on a substandard lot.