Electrical Pullbox

I have had similar experience...

Ours was from upstream power distribution boxes being poorly sealed and conduits or duct trenches becoming a viaduct in downpours..

We install CPVC piping as drains to drain off to a lower area, and went on a search & seal venture to prevent further. In one case, we replaced the bottomless box with an enclosed, steel box, with an epoxy coating, sealed covers and sealed conduit entrances. Raychem makes a sealer that is a great help... RDSS. If you use this, make sure of where you put it- as once installed, it's a real adventure to remove it...

I can understand the customer issue with a sump.. I'd be interested in photos and your resolution.

Good luck. May the force be with you.

Thanks!

As Kcox recommended, the source of the water needs to be identified and resolved.

Meanwhile, a single reliable sump is maintained more reliably than several isolated pull box sumps. If there is adequate grade, construct a self priming siphon that siphons the water to a lower elevation. UV will be required to prevent flow stoppage by "growths".

If elevation is inadequate for siphon, construct a low elevation sump properly positioned to siphon all pull boxes. Reliably remove accumulated water from the single sump with dual redundant powered sump pumps at the holding/pumping area.

You could line the pull box with Vandex a hydrualic Render (Dam Tite is a cheaper DIY solution) assuming you have not constructed a drain in the base of the pull box.

But I assume that the water table was not present at that elevation when the pull box was installed, and was it ever identified on the A&E's Hydrology report.

Therefore is it a seasonal occurance or do you have a new source creating it. Constructing well points, french drains or peforated pipe drains may help to lower the table. Or the the use of geo-synthetics to prevent a moisture barrier.

Also has any additional fill been brought in to the area that has different properties to the native (more clay content) that has created a restriction to the normal disribution of ground water or is it the bearing weight of the new construction affecting the water table.

I am in FL. Rule is: all pull boxes are filled with water all the time. We try and engineering the conduit runs to provide a drain from the ducts into the pull boxes, but we also engineer the cabling to be water tolerent. I don't think that a waterproof duct system would be practical here in FL.

Thank you all for your contributions.

There was no data on seasonal changes, and the water table was low when we did the soil study. We also had to place more fill to the plant. However, In some way, I think Phil is right in which is very difficult to not have water in some areas, and we did buy direct burial clable even though we used pvc conduit and this concrete boxes. The problem is the client wants something from the supplier saying that the cable is for underwater use, and the supplier says that underwater use is another aplication, but however the cable should "temporarily" withstand to be under water.

In any case part of what was said above is a possible solution, but a very expensive one at this stage. We will try to fight it and see what we can come up with.

Thanks again!