Water shouldn't be in there.Is it water or fuel you here?Are there drains or are you hoping water will come out the leaks.
If there are leaks standing water may not come out there. In the water the pressure is higher and and the water pressure
may distort the tube enough to leak.There may be access holes in the top of the tubes.
The tubes may be compartmentized so water doesn't flow.
ABSOLUTLY DO NOT ATTEMPT TO INTRODUCE PRESSURE INTO THE TUBES.