Hidden leak? Help!

[Water girl]

First, thanks to anyone for help! I'm trying to find what seems like a hidden leak, I can't figure out what's going on, ive been hearing running water coming from the upstairs shower wall, my water bill's tripled, my less than 2 yr old water heater sounds like running water 24/7... Here's a more detailed problem list:

-my water bill has been much higher for four months (twice as high for the first two months and now over three times high in the last two)
-the water company stopped by and left a note saying unusual high usage. Leak likely
-for months I've been hearing a noise of what sounds like running water through a pipe behind the wall of the upstairs shower. It can be heard from inside the bathroom, from the shared wall in the bedroom next to the shower upstairs and from the same two walls directly downstairs from the shower. It never stops even if there's been no recent usage of that entire bathroom... Only stops when the water to the entire house is turned of. (The sound is not very loud, if the tv or fan's on it would be very hard to hear.)
-for months there's been a water running sound coming from the water heater I think for 24 hours a day. This sound stops when water to entire house is turned off
-other than the noises and the insanely high water bill there seems to be no other evidence of a leak at least that I can find. I've looked and listened with the water on and off to walls, looked around the exterior of house, carefully looked for wet or possibly warm floors... only thing I havent thoroughly seen is the wall next to the water heater from the inside of the garage due to stacked boxes but floor looks clear and base of water heater looks dry.
-also, another thing that may be nothing but I noticed in the last couple days that we've been keeping the water to the house turned off is that the other upstairs shower in the master bath has a kind of loud echoing sound coming from it

What could this be?? I can't afford to hire a plumber to do hours of 'diagnosing' and having to open walls or floors, any suggestions at all would be soooooo appreciated!! Thanks!

[-and for a little history, this house has copper pipes roughly 30 years old, all showers have original fixtures except for the upstairs shower i originally mentioned has a rain shower head. And about four years back we had water coming up from the wood floor in the downstairs bedroom underneath the room with the shared wall to this shower- was a leak in the slab. ~two years back we had a pinhole leak in the wall of that same downstairs bedroom but about four feet over from where I can currently hear the running water. We also had a pinhole leak behind the wall in the master shower ~five years back (I have really good ears and in the past the pinhole leaks weren't too hard for me to figure out and locate...the current sound is different more like running water).also, ten+ years back we had a hot water leak in the slab in the downstairs guest bath.]

 

[Reach4]

Turn off valves, and see if that sound goes away. Based on your symptom, I would start with the valve that stops cold water from entering your water heater. If you leave that valve off, turn the water heater to "vacation" or off.

Many/most water meters have an indicator that is more sensitive to flow. You could check that as an alternative to listening.

If you have leaking in a slab, one solution is to repipe with pipes, such as PEX, going through the attic. That would bypass the leaking pipe in the slab.

Terry has mentioned leak finding services that have equipment that can listen better than ears, and can figure out where the leak is.

City water or private well? If private, you would probably want to get a water test to see how corrosive your water is. The test would provide more useful info.

 

[Sponsor]

 

[FullySprinklered]

Last call I had like this the yard guy left a spigot running on the back of the house.

 

[WorthFlorida]

Your water meter has a small pin wheel shaped like a triangle or star and it spins with the smallest water use. As you turn off valves you can look at it to determine if it stopped instead of relying on your ears. Some meters are digital and it will have a flashing arrow pointing toward your home that water is flowing.

 

[Dj2]

Your pipes are falling apart, you may be very close to a re-pipe job.
You know it's a bad sign when the water company leaves notes on your front door.
As much as you dislike plumbers, you will need one to re-pipe, this time don't run pipes under slabs, but inside walls and attic.
There are plumbers who only do re-pipes, get at least 3 of them to bid, check their references and if you can, check their previous jobs. These plumbers are usually faster than regular plumbers. Make sure that the bids mention everything, including closing walls, so that there will be no doubt of what's covered and what's not.