Hidden Underground Junction Box


New member
Nov 20, 2016
I have a sylvan in ground pool from 1976. I went to turn my pool on at the electrical panel on Thursday the GFCI breaker won’t turn on. It just immediately trips.

I followed the wires out to a Switch box on the back of my house and I see all the wires coming from my panel. I have a Blue, Red, Green and 2 Whites.

I disconnected the Blue and corresponding White wires that connect to the GFCI breaker. With those wires disconnected, the breaker turn on and stays on, so I know the breaker is good.

There are 2 sets of wires leaving that switch box. They are just typical Black, White and ground wires. I opened up the outlet box that my pump connects to, which is a L6-30 twist lock outlet. Inside the outlet I have a Blue, Red, Green, and 2 whites.

The L6-30 looked kind of rusty so I removed it so I could replace it.

While it was removed, and all the wires separated, I tried the breaker and it still flips right off, so there must be a wiring issue underground.

There are no other electrical boxes, other than the one used to connect to my light, which I removed a few years back.

Since the color of the wires near my house, is different than the wires at the pump outlet, there must be a junction box underground.

Does anyone have any knowledge of where the underground box may be? I know no one can give me the exact coordinates, but maybe there is some convention.

My pool is about 30 yards from my house and the pump pad is on the far side of the pool from my house. I’m about to start digging like I’m looking for Blackbeard’s hidden treasure. Any educated guesses would be appreciated. For instance, would it be between the house and the pool? On far side of the pool near the pump pad?

The wires leaving the box at the pump pad are in metal conduit. My options seem to be work back from the pump pad and dig a hole every 3 feet or so and try to follow it, but then i might miss it. I could trench all the way from the pump pad, but if its closer to the house that’s a lot of digging. I could rent a metal detector to find where the conduit goes and take a wild guess and start digging. I can't start digging from the house because there is a drip septic system between the pool and the house.
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Mod Squad
TFP Expert
LifeTime Supporter
Jul 7, 2014
Bedford, TX
Hi Jim,

While it is possible someone illegally put a junction box underground, it is highly unlikely..

I tried very hard to understand your description, but am confused... How about a few pics of the various boxes with some details..

One thing that confuses me is what is where??? Try to tell us, in order, where the power comes from and where it goes... As an example....something like.. "From a 20 amp GFCI breaker in the main house circuit breaker, to a sub panel on the back of the house, to a switch panel at the equipment pad, and then to the pump outlet... " I'm sure this is not correct, but we need that type of description, if you want us to help..


Jim R.

Rocket J Squirrel

Bronze Supporter
Jun 7, 2018
Alamo, CA
I spent weeks looking for my second junction box. I have 2 lights, and one j-box was immediately obvious. The 2nd one could not be found by me or any of the pool remodel guys. I did rent a metal detector with no luck, but my conduit is PVC. Metal conduit might be magnetic if you're lucky.

Long story short, my 2nd j-box was under the concrete patio on the side of the pool. It was covered by a heavy round cement plug stamped ELEC. When we moved in, I didn't bother to pull off the plug and see what was under there. Instead, I covered it up with a piece of outdoor furniture and completely forgot it existed.

During my long search for it, someone mentioned it might be underground, even though I knew that was not up to code. And so it was. Hidden by the furniture I'd placed there to hide it 6 years prior.

Moral of story: it could be anywhere, code or no code.


New member
Nov 20, 2016
there must be a box because the type of conduit and color and number of wires is different at each end. i'll try to be more clear. i have a flex metal conduit from the gfi breaker in my main electric panel that goes through the back wall of my basement to a 1 gang switch box on the back of my house. in that box i can see the blue and white wire that connects to the gfi breaker. in the switch box i removed the wire nuts that connect the blue and white wire and separated them so none were touching. when i did this i could turn the breaker on and it held. coming out of this switch box is pvc conduit. it has what looks like (2) 12/2 looking wires. what i mean by that is a bare-copper/white/black combo in plastic housing. there are 2 of those that go into the conduit and into the ground. at my pump pad, which is on far side of pool from the house, i have 2 metal conduits coming out of ground into a 1 gang box with a L6-30 outlet for my pump. I ve spent all afternoon digging so i know that one metal conduit goes to the box near my pool light. the other metal conduit follow the first one and keeps going around the pool in a wide radius and then aims toward my house. somewhere there must be a junction where the conduit and type/color of wire changes over. i guess tommorow i will keep digging. the last hole i dug i did not find the conduit, so it must have veered off. as i am typing this i am remembering a weird piece of 4x4 that barley stick out of the ground along my fence, but it sticks up enoght that i,ve hit it with the mower. if the conduit veered in one direction it may be going toward that. maybe thats a marker. I want to thank everone for taking their time to reply on this holiday weekend.