How to find easements on your lot before building a casita
Updated October 12, 2026
Short answer: easements are usually drawn on your subdivision's recorded plat map and listed in your title insurance policy, not on the county's parcel map. Find your subdivision's plat through the Maricopa County Assessor and Recorder, look for strips marked P.U.E., drainage, irrigation or trail, and keep the casita off them.
What an easement is, and why it matters for a casita
An easement gives someone else the right to use a strip of your land, like a utility running power lines along the back fence or a trail crossing several backyards. You still own the land, but you usually can't build on it. For a public utility easement, Arizona's ADU law is explicit: no ADU on top of it unless every utility using it agrees in writing.
Common easements on Valley lots:
- Public utility easements (P.U.E.), often along the rear or side lot lines.
- Drainage easements that carry storm water between lots.
- Irrigation easements in older neighborhoods with flood irrigation.
- Trail or bridle path easements in some equestrian and planned communities.
Why online tools (including ours) can't see them
The county parcel map and building outlines that CasitaFlow and most map sites use show where your lot lines and buildings are. Easements live in recorded documents, mainly the subdivision plat, so a drawing can put a casita right on top of one. Always check before you design.
How to find easements on your lot
- Check your title policy. The title insurance policy from when you bought the home lists recorded easements in its exceptions (often called Schedule B). It's in your closing documents.
- Find your subdivision and its plat number. Look up your address on the Maricopa County Assessor site. Your parcel's details and the assessor's parcel map show your subdivision name and its "MCR" number, the book and page where the plat is recorded.
- Open the recorded plat. Use that book and page at the Maricopa County Recorder. If an older plat is hard to read, the county's plat index FAQ explains how to request a clean copy.
- Read the plat. Find your lot number, then look for dashed lines and labels such as "8' P.U.E.", "D.E." (drainage easement), "irrigation" or "bridle path". The plat shows the width, measured from your lot line.
- Not in a recorded subdivision? A land surveyor or title company can find easements recorded in separate documents.
- Before anyone digs, call Arizona 811 to have underground lines marked. It's free.
Once you know where they are
- Keep the casita clear of every easement and the setback, whichever reaches farther into the yard.
- If CasitaFlow's drawing lands on an easement, use Show another spot under the drawing to see other places it fits, or tell us with Something look wrong?
- Show the easements on your site plan when you apply for a permit. The city will check.
Type your Mesa, Tempe or Gilbert address. CasitaFlow pulls your parcel and zoning and shows the largest casita allowed, the setbacks, and a drawing of where it fits. Free, no account needed.
Common questions
Can I build a casita over an easement?
Not over a public utility easement unless every utility using it gives written consent (A.R.S. 9-461.18). Other easements, like drainage, irrigation or trail easements, usually don't allow buildings either.
Where are easements usually on a lot?
Most often along the rear or side lot lines, for utilities, drainage or irrigation. Some subdivisions also have trail or bridle path easements across backyards.
Why doesn't the county parcel map show my easement?
Parcel maps show lot lines, not easements. Easements are recorded on the subdivision plat or in separate recorded documents.
How wide is a utility easement?
It varies. Widths of a few feet up to 10 feet or more are common along rear lot lines; your plat shows the exact width.
Does a setback start at the easement?
In Tempe, if a utility easement is wider than the 5 ft setback, the ADU has to stay out of the whole easement. Anywhere, the casita has to clear both the setback and the easement.
Sources: A.R.S. § 9-461.18, subsection E; Maricopa County: finding easements on your property; Maricopa County plat index FAQ.