For the orderly development of the town of Mesilla the town is divided into zones, identified as:
RF
Rural Farm
RA
Residential/Agricultural
R-1
Single-Family Residential
R1M
Single-Family Residential with Mobile Homes
MER3
Single-Family Residential – One-Acre Minimum
MER4
Single-Family Residential – One-Half-Acre Minimum
MEH
Holding Zone for Vacant Land
GI
General Industrial
H-R
Residential Cultural – Historical
H-C
Historical Commercial
C
Commercial
(Prior code § 11-2-3.1; Ord. 94-06 § 1; Ord. 2009-05 § 4)
The location and boundaries of the various zones shall be shown on the “official zoning map” of the town which shall be made a part of this title, and all notations and information shown on the map shall be a part of this title as if fully described. The official zoning map shall be identified by the signature of the mayor attested by the town clerk-treasurer, and bearing the seal of the town under the following words: “This is to certify that this is the official zoning map referred to in Chapter 18.15 MTC,” together with the date of adoption of the ordinance codified in this section.
(Prior code § 11-2-3.2; Ord. 94-06 § 1; Ord. 2009-05 § 4)
Where uncertainty exists as to the boundaries of any zone shown on the official zoning map, the following rules shall apply:
A. 
Where such boundaries are indicated as approximately following street and alley lines or lot lines, such lines shall be construed to be such boundaries.
B. 
Where a zone boundary divides a lot or parcel, the location of such boundaries, unless precisely indicated on the official zoning map by dimensions, shall be determined by the use of the scale appearing on the zoning map.
C. 
If a public street, alley, or right-of-way, or public easement is vacated the area vacated shall acquire the same zone classification as the property to which it reverts.
D. 
Should any uncertainty exist as to the boundaries between zones, the commission shall, by written decision, determine the location of the zone boundaries.
(Prior code § 11-2-3.3; Ord. 94-06 § 1; Ord. 2009-05 § 4)
All amendments to and changes in the official zoning map shall be recorded at the end of each fiscal year upon a new copy of the official zoning map. All changes made upon the official zoning map must be by vote of the board of trustees.
(Prior code § 11-2-3.5; Ord. 94-06 § 1; Ord. 2009-05 § 4)
All new construction, building, improvements, alterations, or enlargements made after the effective date of the ordinance codified in this title within the town shall conform with the requirements, character, and conditions as to height, area, and yard requirements established by this title. It shall be unlawful for any person to erect, construct, establish, alter, or enlarge any buildings, or structures in any district contrary to the provisions of this title.
(Prior code § 11-2-3.6; Ord. 94-06 § 1; Ord. 95-03 § 4; Ord. 2009-05 § 4)
When a use is not specifically listed in the section devoted to uses permitted, or conditional uses, it shall be assumed that such uses are prohibited unless a written recommendation from the planning commission to the board of trustees is approved by the trustees, which states that the use is similar to and not more objectionable than the uses already listed.
(Prior code § 11-2-3.8; Ord. 94-06 § 1; Ord. 2009-05 § 4)
Except as provided in this title, no yard or other open space about any building or structure for the purpose of complying with these regulations shall be considered as providing a yard or open space for any other building or structure on the same property or on contiguous properties.
(Prior code § 11-2-3.9; Ord. 94-06 § 1; Ord. 2009-05 § 4)
Where property has not been specifically included within a zone or where territory has become a part of the town of Mesilla by annexation and the current zoning attached to the annexed territory does not correspond to an established zone in the town’s ordinances, then the property shall automatically be classed as lying in the MEH zone until such classifications shall have been changed by an amendment to the official zoning map. If the current zoning attached to the annexed territory corresponds to an established zone in the town’s ordinances, then a request for said zone designation shall accompany the petition for annexation as submitted to the planning, zoning and historical appropriateness commission. The zoning classifications for properties addressed in this section shall become official upon amendment of the official zoning map of the town of Mesilla.
(Prior code § 11-2-3.10; Ord. 94-06 § 1; Ord. 2004-02 § 1; Ord. 2009-05 § 4)
This title does not require any change in plans, construction, or designated use of a building or structure for which a valid building permit has been previously issued and construction has begun at the effective date of the ordinance codified in this title or any amendment; provided, that such construction and/or proposed use of such building is not in violation of any other ordinance or law; and further provided, that the building or structure is completed within one year of that date. “Construction” is defined to be the placing of construction materials in their permanent position fastened in a permanent manner, except that where a basement is being excavated such excavation shall be actual construction, or where demolition or removal of an existing structure has commenced preparatory to rebuilding, such demolition or removal shall be considered construction.
(Prior code § 11-2-3.11; Ord. 94-06 § 1; Ord. 2009-05 § 4)