What does Scottsdale's Environmentally Sensitive Lands ordinance mean for a North Scottsdale hillside lot?

Scottsdale's Environmentally Sensitive Lands ordinance, called ESL, is a set of zoning rules for the city's desert and mountain land, and on a North Scottsdale hillside lot it decides how much of the lot has to stay natural desert and what can be built on the rest. A recorded Natural Area Open Space easement can mark part of a lot as permanent desert, and the city's guide says no grading, filling, clearing or excavation is allowed there and that walls, pools and barbecues may not be built in it.

I'm Jen Keene, a REALTOR® with eXp Luxury in Scottsdale, AZ, helping buyers and sellers across Scottsdale, Fountain Hills and North Phoenix for more than 20 years. The City of Scottsdale decides what applies to any one lot, so everything below comes from the city's own pages and the Scottsdale Revised Code, and the last step on any lot is a conversation with the city's Planning and Development Services and a licensed professional such as a surveyor, civil engineer or land use attorney. If you have an address in mind, call me and I'll check what the city has on file for it.

According to the city's ESL Overlay page, the ordinance covers about 134 square miles of desert and mountain areas north and east of the Central Arizona Project canal. The city's Citizens Guide says the City Council adopted it in 1991, and the Arizona Municipal Water Users Association, in a 2015 piece on growth and conservation, also dates it to 1991 and says it shapes the location and size of development in about two-thirds of the city. In the code's words, the ESL regulations apply to development in the ESL district, and where they conflict with another provision of the Zoning Ordinance, the ESL regulations prevail.

The city publishes the maps itself. Its ESL Overlay page links an interactive map of ESL landforms and a PDF index map of protected peaks and ridges, and the city's maps page lists ESLO maps for the ESL areas and the Natural Area Open Space areas. The city's Property Information Request tool looks up a property by street address or parcel number and returns details such as its zoning, FEMA flood zone and parcel area. That page says its information should not be relied on without field verification and suggests checking the title report and the HOA for additional restrictions.

The Scottsdale Revised Code says a zoning district where the ESL rules apply is identified with the suffix ESL, so look for it in a lot's zoning. The code says the city may apply the ESL district to land with conditions such as slopes of 15 percent or greater, unstable slopes, protected peaks and ridges, boulder features, watercourses, shallow bedrock, undisturbed native vegetation and wildlife habitat, and it sorts the land into three landforms: Lower Desert, Upper Desert and Hillside.

The landform matters more than the word hillside in a listing. The amount of land a lot has to leave natural depends on the landform and the slope, and a lot that looks like a hillside lot may be mapped in a different landform. The city's Citizens Guide, a June 2004 document the city still posts on its ESL page, describes the Hillside landform as the significant peaks, mountains, buttes and hills of the northern parts of the city, with steep slopes of 15 percent to over 50 percent.

NAOS stands for Natural Area Open Space. The code sets aside a percentage of the land containing natural desert as NAOS, and the city's ESL page has a table that sets the percentage by landform and slope, and the Lower Desert and Upper Desert columns are lower. In the Hillside column the current table asks for 50 percent on slopes up to 15 percent, 65 percent from 15 to 25 percent and 80 percent over 25 percent, with a stated minimum of 40 percent after reductions where they apply.

The preserved land stays private. The city's Guide to Natural Area Open Space says the land is owned by a homeowners association or an individual, and that the easement acts as a deed restriction. It also says easements are dedicated either in common tracts within a subdivision or lot by lot, so the easement may be on your own lot or in an association tract. The code says the whole NAOS area is permanently maintained as NAOS through easements, donation or dedication, that common-tract NAOS is shown on the subdivision plat or map of dedication, and that on an individual lot the property owner is responsible for maintenance.

On what an owner can do, the guide and the city's form of easement agree: the guide says no grading, filling, clearing or excavation of any kind is permitted in the easement and that walls, pools and barbecues may not be built within it, and the form says the owner shall not grade, grub or excavate the easement or build any structure on it except as the city approves in writing. The form also says the owner restores the easement under city-approved plans if it is disturbed, and that the city may go to court to stop a violation and may enter the property to enforce it.

The code adds that clearing, pruning, raking and landscaping within NAOS are prohibited except in limited cases, and that dead or dying native plants within NAOS are left in place as wildlife habitat. Fire safety has its own allowance. The code permits a defensible space around homes in mapped wildland and urban interface areas, including removing flash fuels such as invasive annual grasses within 30 feet of a habitable structure without destroying native plants, and the city's NAOS guide says the Fire Department has approved a defensible zone within 30 feet of a habitable structure with city approval. Scottsdale also has a pending text amendment on fire defensible space in the ESL area (Case 11-TA-2000#4), which the city's project narrative shows as initiated on July 2, 2025. The Planning Commission continued it to a date to be determined in April 2026, and the city's case page still lists the hearing date as to be determined, so ask the city what applies today before clearing anything. The McDowell Sonoran Preserve Commission's January 8, 2026 minutes record city staff saying the amendment does not govern Preserve lands.

The code's stated purpose for the ESL district includes protecting people and property from hazards it names as rockfalls, rolling boulders, other unstable slopes, flooding, flood-related mud slides, subsidence, erosion and sedimentation.

When NAOS is placed on individual lots, the code requires a construction envelope. The code also says no one may grade, clear, grub, remove plants or do other site preparation on a property until the applicable NAOS plan has been approved and the permits have been issued, so the order of approvals matters before any dirt moves.

On washes, the city's ESL page says the goal is to leave washes in place and in natural conditions where practical. When a change is necessary, it has to follow Chapter 37 of the city code on floodplain and stormwater regulation and the city's Design Standards and Policies Manual, and the page says the Zoning Administrator may approve a wash modification if the drainage design is acceptable and the purpose of the ESL is met. Confirm with the city for any lot with a wash on it.

The review depends on the lot and on what was approved when its subdivision was built. The code says applications for preliminary plats in the ESL district are reviewed for ESL compliance and need Development Review Board approval, and that single-family homes that are not part of a plat and are proposed in the Hillside landform are reviewed for site design criteria and need approval from the same board. The code also lists what an ESL application includes, such as an ALTA survey, a slope analysis with a NAOS calculation table and a geotechnical report for sites with shallow bedrock or boulders. Ask the city for the requirements that apply to your project.

Existing neighborhoods can follow older rules. The Citizens Guide says existing projects and neighborhoods are allowed to follow the rules in force when the development was approved, with minor exceptions, and the code's exemption schedule is built around development approved before May 21, 2004. The guide also says that for a home in a recorded subdivision with amended development standards, or in a master planned community, additions are allowed under those amended standards, and that new buildings on other properties must meet the ESL standards unless the City Council grants a hardship exemption. So which rules apply to a lot depends on when and how its subdivision was approved.

The city's ESL page says the wash modification process begins with a pre-application, and links its pre-application process. A pre-application meeting is the way to ask the city which review a pool, casita or addition needs on a specific lot.

These are the documents and checks worth asking for, and each one points to a place the city's own materials name.

1. The ESL landform and zoning. Look the address up on the city's ESLO maps and in the Property Information Request tool, then confirm with the city.
2. The recorded plat or subdivision documents. The code says common-tract NAOS is shown on the subdivision plat or map of dedication, and it requires construction envelopes where NAOS is on individual lots.
3. The preliminary title report. The city's guide says a NAOS easement should show up on the current complete title report under Schedule B or on the subdivision plat.
4. The recorded easement itself and its exhibit map. The exhibits show where the easement sits on the lot, and the city's form says it runs with the land.
5. Where the house, pool, walls and barbecue sit compared with the easement. The city says structures including walls, pools and barbecues may not be built within it. A licensed surveyor can mark the line, and a land use attorney can tell you what an existing encroachment means for you.
6. Any recorded release of easement or city approval for what is already built. The Property Information Request tool searches building permits and other city records for the address.
7. The association's documents, which have their own rules. Here's an explanation of HOA rules and regulations in Arizona.

Those requests belong inside your inspection period, so ask for them as soon as the offer is accepted. Here's how the inspection period works in Arizona, and if you'd like help with the list, call me and I'll check what the city has on file for the address.

A buyer who finds a home with natural desert behind it and wants a pool should first find out whether that desert is NAOS. The steps are to read the plat and the Schedule B items on the title report, find the easement and its exhibit, and look for a construction envelope. If the pool fits inside the envelope and outside the easement, the next question is which city review it needs, and that is a pre-application question for Planning and Development Services.

If the pool or a casita would reach into the easement, the city's NAOS guide says a Release of Easement may be an option. It says a portion of a NAOS easement may be released if an additional, equal amount of natural desert can be dedicated as replacement and the lot still meets the ESL requirements, and that the release process should be completed before any other plan submittal. The code says the Zoning Administrator may release NAOS easements only to the extent the release meets the code's own standards. Nothing in the pages I read promises a release, so a buyer should not write a pool into a purchase plan until the city has said yes.

Send me the address and I'll check what the city has on file for the lot, including its zoning and landform on the city's tools. If you're also looking at North Scottsdale real estate more broadly, or want the full buying process in Arizona, those are here too.

For the specifics on a lot, the City of Scottsdale decides. Planning and Development Services is the department to confirm with. The city's ESL page lists 480-312-3111, which it presents as the city's general number, and the NAOS guide lists Current Planning at 480-312-2500 and planninginfo@scottsdaleaz.gov. A licensed surveyor, civil engineer or land use attorney can speak to what the recorded documents mean for you. When you're ready, get in touch or call me at (480) 203-6605.