Mountain development.
El Paso City Code § 20.10.370
in effect20.10.370 - Mountain development.
A. Purpose. The purpose of these regulations is to promote the following city objectives within mountain development areas:
1. To protect significant natural features of the mountain development area and preserve the city's unique visual setting as part of the comprehensive plan;
2. To provide an alternative approach to conventional flat land development by allowing transfer of residential densities through clustering of dwellings in order to preserve larger areas of open space;
3. To minimize scarring and disturbances of the natural character of the mountain development area through control of grading and cut/fill operations as defined in the grading ordinance;
4. To control water runoff and soil erosion;
5. To provide a safe means of ingress and egress for vehicular and pedestrian traffic to and within the mountain development area;
6. To encourage sound engineering practices related to mountain development.
B. Minimum District Area. The minimum area for a mountain development district where common or public open space is to be provided shall be one acre. Extensions to the original district, from a common boundary, may be considered in increments of less than one acre, provided, however, that all other requirements are observed.
C. Ownership Control. Where required, the common open space shall be owned by an incorporated or unincorporated association to assure that it will be permanently maintained in its natural state. Open space may be made public if dedicated or transferred in trust to the city and the city council accepts such dedication or transfer without affecting any other provision of this title.
D. Density Permitted. Where the development is for apartments or mixed-use residential development that meet all minimum requirements set forth in Section 20.10.363, density shall be as stated in Appendix B. Where the development is for single-family detached small lot development that meet all minimum requirements set forth in Section 20.10.625, density shall be as stated in Appendix B. For other permitted uses, the maximum dwelling units per gross acre shall be calculated based on the percentage average slope of the property as follows:
Percent Average Slope | Maximum Density per Gross Acre
0 to 5 | 7.0
5.1 to 10 | 6.0
10.1 to 15 | 5.0
15.1 to 20 | 4.0
20.1 to 25 | 3.0
25.1 to 30 | 2.5
30.1 to 35 | 2.0
35.1 to 40 | 1.5
40.1 or more | 1.0
E. Open Space Required. To retain the significant natural features of the mountain development area, common, public or private open space, or a combination thereof, shall be provided as part of a proposed development. The minimum amount of open space to be provided shall be based on the percent average slope of the property as shown below. The required open space within a mountain development district shall be shown on the subdivision plat and detailed site plan.
Percent Average Slope | Open Space Required/Percent of Total Gross Acreage to Remain Percent Average Slope Undisturbed
0 to 5 | 20
5.1 to 10 | 25
10.1 to 15 | 30
15.1 to 20 | 35
20.1 to 25 | 40
25.1 to 30 | 45
30.1 to 35 | 50
35.1 to 40 | 55
40.1 or more | 60
F. Architectural Design Standards. Building and construction materials within a mountain development district shall meet the following architectural design standards:
1. Mirrored surfaces or any treatments that change ordinary glass into a mirrored surface shall be prohibited;
2. Bright untarnished copper or other metallic surfaces shall be treated to reduce reflections;
3. Materials used for exterior surfaces of all structures shall blend in color, hue, and tone with the surrounding natural desert setting to avoid high contrast;
4. Development design and construction techniques shall blend scale, form and visual character into the natural landform, and shall minimize exposed scars;
5. Exterior lighting shall be low scale and directed downward, recessed, or shielded so that the light source is not visible from the adjacent developments;
6. Reflective building materials shall be prohibited;
7. No exterior paint colors shall be used which have a light-reflecting value (LRV) greater than forty percent. (The LRV of a paint is available from paint manufacturers and it measures the amount of light reflected by a certain color.)
G. Property Development Standards. The following property development standards shall apply to all land, buildings and structures within a mountain development district:
1. Subdivision Plat. Buildings and structures in a mountain development district shall be erected only on land where a plat or replat approved by the city plan commission, has been filed of record, and indicates compliance with the provisions of this section. Each attached or detached single-family dwelling must be platted on an individual lot prior to issuance of occupancy permits;
2. Site Plan. A detailed site development plan complying with all of the requirements of Chapter 20.04 (Administrative Review Procedures) shall be required for all property within a mountain development district, except where a development is for single-family detached dwellings meeting the minimum yard requirements of Chapter 20.12 (Density and Dimensional Regulations) and where common or public open space is provided to satisfy the open space requirements of this section. If a development is to be undertaken in a series of phases, a development schedule indicating the proposed phasing shall accompany the required detailed site plan. Where the development is for apartments, or mixed-use residential development that meet all minimum requirements set forth in Chapter 20.12 (Density and Dimensional Standards) and Section 20.10.363, a detailed site development plan shall not be required;
3. Common or Public Open Space. Where required, the total amount and distribution of common or public open space shall be shown on the detailed site development plan and subdivision plat and shall be expressed as the percent of the site which will remain in its natural state. Satisfactory provisions for assuring continued retention of the common or public open space shall be provided;
4. Percent Slope. The percent slope of a proposed mountain development used to determine the common open space shall be shown on the required detailed site development plan and subdivision plat;
5. Perimeter Treatment. The perimeter treatment of the proposed mountain development shall be designed to insure compatibility with adjacent existing or potential development by provision of compatible land uses and structures. A minimum setback of ten feet of separation for each story or fraction thereof shall be maintained between any structure and the outside boundary of the proposed mountain development.
H. Private Streets. Where authorized by the city plan commission in approving a subdivision plat, streets may be privately owned.
I. Preservation of the Environment. In all mountain developments, existing vegetation, animal life, arroyos, floodprone areas, steep slopes, and other natural features shall be considered in the planning, design and layout of buildings, service areas and location of streets in the allocation of open spaces reserve the natural environment.
J. Right-of-Way and Pavement Widths. The right-of-way and pavement widths for internal ways, streets and alleys within and adjacent to the proposed mountain development shall be:
1. Determined from the standards contained in the city's current subdivision regulations and any applicable ordinance governing streets;
2. In conformity with the estimated needs of the entire mountain development and the traffic to be generated thereby;
3. Adequate and sufficient in size, location and design to accommodate the maximum traffic, parking, loading needs and the access for firefighting equipment vehicles while preventing undue scarring and grading.
K. Off-Street Parking and Loading. The minimum requirements for off-street parking and loading shall be satisfied as set forth in Chapter 20.14 (Off-Street Parking and Loading Regulations).
L. Utilities and Public Services. Every mountain development shall be adequately served by essential utilities and public services such as water, sanitary sewer, storm drainage, police, fire and other similar services.
M. Property Grading Standards. Grading in a mountain development shall be in accordance with Chapter 18.44 (Grading) of this Code.
(Ord. 16905 § 1, 2008; Ord. 16653 § 2 (part), 2007) (Ord. No. 19244, § 15, 10-12-2021; Ord. No. 019815, § 3, 11-18-2025)
Source: City of El Paso, City Code and City Charter (Municode Library, library.municode.com)URL: https://library.municode.com/tx/el_paso/codes/code_of_ordinances?nodeId=TIT20ZO_CH20.10SUUSRE_20.10.370MODEFetched: 10/28/2026