# Feelings on URD, in flood prone area



## Bluzman (Jun 5, 2011)

Hi all,
Have a customer who is interested in installing an underground service. They live right on a canal , south shore of Long Island. Whats the general feeling about installing URD AL, conductors underground in an area which could have a salt water bath several times over the course of years to come ? Would conduit help or hurt ? 
Thanks


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## Big John (May 23, 2010)

If anything I'd expect a conduit to fill and trap saltwater. At least with direct-burial you're just dealing with ground saturation.

That said, in theory the cable will withstand even saltwater easy enough, and if it does fail then obviously conduit makes repair much easier.

Maybe price both options for the customer and let them make the decision.


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## telsa (May 22, 2015)

You missed it.

That close to the ocean you don't want aluminum above or below ground.

The TERMINATIONS will absolutely suffer from the local salt air.

Having spent decades just off the water in Hawaii -- I can assure you the salt effect is a PITA.

How bad?

HECO -- the local Poco -- had to call in outside (mainland) experts to figure out why their new, ultra expensive, high voltage main power link to the city kept faulting out.

ANSWER: salt was being carried in -- even a mile from the sea -- and building up around the naked HV cables. Then, during fog, early morning dew, the arcs would begin to jump. 

For HECO, that jumping was immense. But it happened anyway.

HECO had to spend millions to have a specialist chopper crew to fly near the cables and spray high pressure fresh water to wash off the salt. It took months.

For the typical Service, the salt gets to screwing up the bus. I had a 2% voltage drop right at my panel. 

( From the aluminum busing to theC/B load side connection !) 

It went away after it was re-polished. That's how much corrosion occurs when you are right on the water. And, yes, this was an interior NEMA1 (warehouse) panel. 

I not only would not recommend aluminum conductors - - I would not recommend aluminum busing.

But, that's me. YMMV.

Away from salt// chlorine -- I love aluminum -- and use preferentially. 

Some time, take a hunk of feeder aluminum scrap and drop it in a solution ol table salt and water.

Come back in a week. Heh.

Chlorine gobbles up aluminum like Pac Man.


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## Bluzman (Jun 5, 2011)

*Big John*, I was on the same page in my thought process, The conduit will hold the salt water but make replacement easier if there is a problem.

As for the conductors *Telsa *your feeling is Copper direct burial ? 
There would be no exposed ends except in the meter pan which would be the same even if it were an overhead service, So the salt would need to break down the jacket of the URD. This is why I was thinking Al would be ok, But I am understanding your points. 
Thanks


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## backstay (Feb 3, 2011)

Conduit no matter what.


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## LGLS (Nov 10, 2007)

Bluzman keep in mind if you do use conduit there are a lot more special LiPSE&G regulations including handholes that must be used. Also I take it this is bayfront and not oceanfront property?


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## Bluzman (Jun 5, 2011)

Good point island guy. Yes I would need to put some form of property box for the utility to have an access point.


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