Clearance to overhead power lines

[Robert Foster]

Today's house was sited on a hill which fronted a main road and the overhead power lines went right across the front yard about 12 feet above the ground. There must be a minimum for this but a quick google came up short...so I thought I'd ask here instead of being on hold forever with the power company.

Just to be clear...these lines are not the service drop to the individual house. The lines are the distribution (maybe transmission , not sure what the accurate terminology would be) lines serving many houses.

[ken horak]

If they are not overhead service conductors then they are under the control of the utility company and their rules. The NEC does not cover electric utilities distribution lines.

If they are the service entrance conductors- then over residential property and driveways, where the voltage does not exceed 300 volts then 12' is the lowest it can be.
If they exceed 300 volts then the height is 15'

[Robert Foster]

Thanks for the reply Ken.

I finally got to talk with an engineer at the local power company.

This cable is considered a secondary distribution cable and is required to be a minimum of 15 feet above grade.

[JB Thompson]

Interesting that distribution lines only have to be 15 ft. Service drops must be higher.

E3604.2.2 Vertical clearance from grade.
Service-drop conductors shall have the following minimum clearances from final grade:

1. For service-drop cables supported on and cabled together with a grounded bare messenger wire, the minimum vertical clearance shall be 10 feet (3048 mm) at the electric service entrance to buildings, at the lowest point of the drip loop of the building electric entrance, and above areas or sidewalks accessed by pedestrians only. Such clearance shall be measured from final grade or other accessible surfaces.

2. Twelve feet (3658 mm)-over residential property and driveways.

3. Eighteen feet (5486 mm)-over public streets, alleys, roads or parking areas subject to truck traffic.

[Jerry Peck]

Interesting that distribution lines only have to be 15 ft. Service drops must be higher.

The utility has deeper pockets and can write a bigger check. :)

[ken horak]

Different codes and different code making panels.

[Jerry Peck]

Different codes and different code making panels.

Yes, but ... the voltage is still the same, and its ability to kill people is still the same, and if the location is the same, then the rules should be the same.

There is really no reason to allow running a 7.6kv/13.2kv line at 15 feet when an overhead service drop of 120v/240v is required to be at 18 feet minimum.

[brian schmitt]

the utility companies normally use the NESC (national electrical safety code) FYI