We have a 4 story - 35 unit bldg. we hear water rushing (as though tub on full blast) each unit checks out fine, no leaks, and nothing pooling. Water bill costs over $8000 monthly how can we pin-point location to turn off the water?

We have a 4 story - 35 unit bldg. we hear water rushing (as though tub on full blast) each unit checks out fine, no leaks, and nothing pooling. Water bill costs over $8000 monthly how can we pin-point location to turn off the water?
How to find rushing water source without leaks or flooding?

Do pipes run underground after they go through a meter?

How about cooling loop makeup water, if the building uses a chiller?

How is the building metered?

Are there isolation valves available? By floor? By unit?

1. Pipes are underground after they go through meter
2. Cooling loop no
3. City meter outside in sidewalk
4. Isolation valves just for appliances, main shut-off to bldg.

Seems like you don't have one of the most important techniques of isolation. The lack of isolation is very bad. We had to shut the whole industrial building down just to change the valve on a Urinal.

I would seriously think about an underground break. You may not even have access to the meter making things even more difficult. At a minimum, I would suggest having an inside valve installed, possibly with a meter as well. I've heard instances where meters in the sidewalk may not go just to your building, but you actually may be paying for someone else's water use, because someone forgot that you were once the last building metered.

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