Easements, Power Lines and Utility Restrictions

Setbacks are visible on any zoning map. Easements and utility restrictions are the invisible constraints — and they're where feasibility surprises usually come from.

What's an easement?

An easement is a legal right someone else holds over part of your land. You still own it; you just can't build on it (or sometimes even plant over it). Common ones:

Utility easements. Strips reserved for power, water, or communication infrastructure — often along the rear or side property line, exactly where you want your ADU. Widths of 5–10 feet are common.

Sewer easements. A public sewer main may run through your lot. You generally can't build over it, and even your own private sewer line matters: building over it may require rerouting, which adds real cost.

Drainage easements. Reserved paths for storm water. Blocking them is not an option.

Easements show up on your title report and often on the county's recorded maps. Finding them is a standard part of a professional feasibility review — and a terrible thing to discover during plan check.

Overhead power lines

Utilities like LADWP, Southern California Edison, and PG&E require minimum clearances between structures and their overhead lines. A line crossing your back corner may be a non-issue for a single-story ADU but a hard stop for a second story — roofs, decks, and even workers during construction must stay outside the clearance zone.

If lines cross your property, get the clearance requirements from your utility early. Sometimes the answer is adjusting the ADU's placement; sometimes it's choosing one story instead of two; occasionally the utility will relocate a line — for a price and on their timeline.

Why this lesson matters

Almost every horror story that starts "the city approved our plans, but then…" involves something in this lesson. Easements and utility clearances don't show up in a Zillow photo. Check them before you design, not after.