ECN Forum Forums Code Related Discussion NEC & other Code issues Walkway and boat dock

I have a walkway to a boat dock that I'm going to have to wire and install at least 3 lights on each side, then pull the switch leg to lights that are going to be under the canopy of the boat dock. I'll have 3 general use outlets on the boat dock that are NOT for boat lifts. Just for a charger and general use purposes. I know that all has to be on GFCI protected circuit, etc. Right now I'm just in the process of figuring out the best way to run my pvc along the walkway to the lights and boat dock. Problem I can't seem to figure out now is that pvc has to supported every 3ft. The pilings are approx. 8 to 10ft. apart. I can't go under the walkway, it is too close to the water. If I put 45's at every piling it's going to look really tacky and hard to pull wire. I'm going to try to post a picture if it works out alright. If not I'll try again in another post. Nope, looks like I will have to try in another post. I'll have to read up on how to get it here. I've already uploaded it to the photo section. Will try again.
Thanks

Hopefully this is 3 photos

Well, only one came through I guess, but this is the main one I'm working on right now. There will be a weather proof panel at the left of the entrance to the walkway, with GFCI breakers for each circuit going to the walkway and to the boat dock. I understand I will have to drive a ground rod, if not 2, at the panel, and will have to have a equopential? ground ring at the panel according to the inspector. Thanks again for your comments..
The lights for the walkway will have to be mounted on the side of the post, due to caps they have put on the top of the pilings. The lights are mainly for illumination so boats can see them instead of running into the walkway. I'm going to try to position them if I can so they will provide light for the walkway also. They have flat caps on the pilings, so I may if I have to, bore through the top of the caps at an angle, and put lights on the top of the pilings. I'm not that far yet.
Thanks again.

Thinking again on the top mounted fixtures. I'd have to be able to use UF cable from the top of the piling to the side where the junction box would be if it is allowed, which I wouldn't think so. It would be hard to get flex or pvc in at that angle....

Thinking about running 1/2" pvc down left side, coming up at light locations into a 7 hole wp 2 gang box, coming back out of 2 gang up to a round wp box for fixture, back out of 2 gang for fixture on opposite side under dock, (hope there's no snakes) 90 ing up to fixture on other side.(Trying to keep most of the conduit where it's not seen as you approach the walkway). Still don't know exactly how I'm going to strap it horizontally though, unless I add some kind of support between the pilings.

Might I suggest a different approach?

Try running strut horizontally, at about 'knee height,' along the walk (the idea is to make it look like it was a middle rail for the walkway). Attach the conduit to the strut using parallel clamps like these: http://www.mcmaster.com/#strut-channel-straps/=12r82g6

I'd prefer coated conduit (Ocal) for this job; in any event I'd use rigid, with threaded fittings wherever possible. PVC just seems to droop and crack. I'd also go up a size, to 3/4".

Forget "Bell" boxes. This is a place for the cast FS-type boxes.

Fixtures are available that will screw directly to conduit. Again, 3/4 rigid will give the support you need.

Coat ALL threads with anti-seize before final assembly, to keep things from rusting together. T&B's "Kopr-coat" is even UL listed for this use.

Thanks for the suggestion of unistrut. I'm trying to get away from metal pipe. Some of the emt I pulled out of the boat house was rusted into and hanging by the wires "with no ground wire in it:( I got the inspector to look at it before I started any wiring, and he said to change it to pvc ( overhead lighting). They(the one's in charge) were going to try to get power put back on it like it was. He said "No way", which is what I wanted him to say. It was easier for him to tell them than me. Didn't want to make them think I was saying that to make my job bigger. Now it is quiet a bit bigger. I've got to pull another feeder from the main building also. The feeder that was feeding it previously was only a piece of 12/2 UF. He wanted me to get a load calculation, etc.. When I told the Executive Director, He said just pull a new one. That's about 220ft. just to the entrance of the walkway underground. Thanks again.. I'll think about the Unistrut...

If you install a PVC-coated rigid conduit like Reno suggests you'll find that it doesn't sag like PVC does and the coating (inside and out) will protect it from corrosion.
Our plant has the worst environment imaginable for corrosion and the PVC-coated conduit installed 12 years ago still looks like new.
It's a bit more money up front but you'll never have to replace it.

You are in Article 555. I don't see anything that limits the height of conduits above the water, in fact the standard practice for boat lifts is to run the conduit under the water.
The limit is for the splices and devices,



PVC seems to be the choice here but we are dealing with salt water, that looks like a lake and it is much more forgiving.
I would run the PVC under the dock. That is also pretty standard here. "T" the "UP"s for the lights, just be sure there are no splices below the dock.

PVC is what I'll be using. My only problem is that I won't be able to run it under the walkway due to not being accessible because of the water level. I'm planning on running it down the left side, but I don't have anything right now to support it too except the post and I'll need some support in between the post. I'll either have to get some sort of bracket or have them nail another piece of 2x12 treated on the outside of the post for me to run my conduit on. Got to have something that won't make it look too tacky.