Power Outages in Derry, New Hampshire

What usually causes power outages in New Hampshire

Large outages in New Hampshire mostly come from nor'easters and ice storms, heavy snow, and wind and falling trees. Between those events, most outages are small: a failed transformer, a tree limb on a line, a car hitting a pole, or an animal in a substation.

In October, the risk to watch in New Hampshire is nor'easters and ice storms and wind and falling trees. When a warning is issued for Derry, charge phones and battery packs ahead of time and sign up for your utility’s outage alerts if you have not already.

First steps if the power is out in Derry

1. Look outside. If streetlights and neighbors still have power, check your main breaker and any tripped GFCI outlet before calling.
2. Report it to Eversource Energy or Unitil. Use the outage line, app or map so a restoration ticket exists for your address, then add a report on this page.
3. Unplug TVs and computers so the voltage spike when power returns does not damage them.
4. Keep the fridge and freezer shut. A closed fridge stays cold for about 4 hours, a full freezer for about 48.
5. Stay 35 feet from downed lines and never run a generator indoors or in a garage.

Food safety times, generator rules and what to keep in an outage kit are in our power outage guide.

How power is restored in Derry

About 33,941 people live in Derry, the 4th largest of the 4 New Hampshire cities on this site. After a large outage, the utility works from the top of the system down: transmission lines and substations first, then the main feeders that serve thousands of homes, then neighborhood lines, and finally single houses with a damaged service drop. Hospitals, water plants and emergency services are put ahead of homes on the same circuit.

That is why the lights can come back on one street while the next one stays dark. If your neighbors have power and you do not, report it again: the fault may be on the line to your house alone, which is a separate repair.

A routine outage from one failed part is often fixed in 2 to 4 hours. Storm damage that needs new poles, or repeated damage to the same line, can take a day or more. Only your utility’s outage map has an estimate for your address.

Frequently asked questions