ESL Overlay

The Environmentally Sensitive Lands Overlay (ESL) is a set of zoning regulations to guide development throughout the 134 square miles of desert and mountain areas of Scottsdale. These areas are located north and east of the Central Arizona Project canal.  Prior to ESL, some properties were established within the Hillside District (PDF).

The intent and purpose of the ESL is to identify and protect environmentally sensitive lands in the City and to promote public health and safety by managing development on these lands. The ordinance requires that a percentage of each property be permanently preserved as natural area open space (NAOS) and that specific environmental features, including vegetation, washes, mountain ridges and peaks, be protected from inappropriate development. Benefits include:

  • Open space between properties and along roadways
  • Maintaining wildlife corridors
  • Protecting native vegetation

ESL Resources and Maps

ESL Overlay Ordinancelinks to external site             

Printable List of Protected Native Plants (PDF)

Indigenous Plant List for ESL

ESL Landforms and Protected Peaks and Ridges Index Map (PDF)

Interactive GIS map showing ESL landforms

Interactive GIS map showing 50 CFS Flow Washes


Click image above to view the brochure.

ESL Overlay Versions

ESL 2004 - Effective 05-21-04  (PDF)

ESL 2003 - Effective 05-01-03 (PDF)

ESL 2002 - Effective 01-31-02 (PDF)

ESL 1991 - Adopted in 1991 (PDF)

Natural Area Open Space (NAOS)

The City of Scottsdale has an ongoing interest in preserving the unique qualities of the Sonoran Desert. This includes native vegetation, scenic corridors, animal habitats, boulder outcroppings, and washes. Scottsdale contains an abundance of diverse native plant and animal species that contribute to its character and beauty. They merit protection under the Environmentally Sensitive Lands Overlay (ESL), as well as the former Hillside Ordinance.

An important part of the ESL regulations is the Natural Area Open Space (NAOS) requirement. The NAOS requirements are designed to preserve the desert in its natural state. NAOS is an effective preservation tool, but its integrity can only be protected and maintained with the assistance of a well-informed public.

The amount of NAOS required to be set aside with each development is based upon two factors -- the landform area and land slopes.

Land Slope Lower Desert Upper Desert Hillside
0 to 2 % 20% 25% 50%
2 to 5% 25% 25% 50%
5 to 10% 30% 35% 50%
10 to 15% 30% 45% 50%
15 to 25% 30% 45% 65%
Over 25% 30% 45% 80%
Min after reductions* 15% 20% 40%

(*If applicable. See Ord. Sec. 6.1060B & Sec. 6.1060Flinks to external site)

NAOS Resources and Maps

NAOS Suitability Analysis  (PDF)

High Priority NAOS Areas  (PDF)

NAOS Easement (PDF)

Confirmation of New Dedication (PDF)

Single-Family Residential Easements (PDF)

NAOS Enhancement (PDF)

Indigenous Plant List

Native Plant Ordinance links to external site -- Protection and transplanting of major native plant specimens; applies to entire city.

Remove Invasive Plants


Click image above to view the brochure.

Native Plants


Native Plant Information

Native Plant Ordinance links to external site -- Protection and transplanting of major native plant specimens; applies to entire city.

Indigenous Plant List

Remove Invasive Plants 


Click image above to view the brochure.

Wash Modifications

The goal of the ESL Overlay is to leave washes in place and in natural conditions where practical. When necessary, modifications to natural watercourses and all walls and fences crossing natural watercourses shall be designed in accordance with the standards and policies specified in Chapter 37 of the City of Scottsdale Revised Code - Floodplain and Stormwater regulation, and the city’s Design Standards and Policy Manual (DSPM).

An application for wash modification may be granted by the Zoning Administrator subject to approval of the design solution for the drainage facilities and subject to the finding that the purpose of the ESL overlay district (Section 6.1011) has been achieved. However, in no event shall the provisions of this section require greater Natural Area Open Space (NAOS) dedication than what are currently required by Section 6.1060 A, B, and C of this ordinance.

Applications must include a description of alternative watercourse management / engineering techniques considered for the site. 

The Wash Modification process begins with Pre-Application. 

Sample of Application for Wash Modification Application Form (PDF)

Hardship Exemptions

On April 20, 2004, the Scottsdale City Council adopted the third set of revisions to the Environmentally Sensitive Lands Overlay District (ESL 2004), which became effective May 21, 2004. As a part of these revisions, a procedure was established that allows property owners to apply for a hardship exemption from the requirements of this newest version of ESL.

Zoning Ordinance Section 6.1022.D. - Exemptions and exceptions. 

If an applicant can demonstrate to the City Council that a hardship is created by the requirement to comply with the new regulations and that relatively little impact will occur from the exemption, then they may be allowed to follow specific regulations of an earlier version of the ESL. Under no circumstances will an exemption be allowed where the property owner’s proposal does not comply with that standard in a previously adopted version of the ESL. 

Contact Information

City of Scottsdale - One Stop Shop
7447 E. Indian School Road, Suite #105
Scottsdale, AZ 85251
P: 480-312-2500

8 a.m. - 5 p.m. M-T, TH-F
9 a.m. - 5 p.m. Wednesdays
No transactions after 4 p.m.