[beeje]

To diagnose your issue; Disconnect your city water. Put some water in your fresh water tank. Turn on your water pump to pressurize the system. Open all fixtures, hot & cold. Make sure the water heater is full and all the air is out of the pipes. Once the entire system is under normal operating pressure, The pump should NEVER come on unless water is turned on at a fixture. If the pump does come on while no one is using the water then you have a leak somewhere.

If you are like most people and you have city water where you camp you would not know if your have a leak until it presents its self by leaking to the ground in some form of fashion.

If you determine that your system is leak free (by doing as stated above )than I would suspect that the very front joint of the corroplast covering is not sealed (none are) and water is being driven in when driving in the rain.

Also check for any other areas where rain water could enter from below, like around the spring mounting points Etc.

Like someone mentioned, I also drilled several holes in the low spots to allow any water that does get in to drain out without collecting on top of the corroplase covering. BE CARFULL WHEN DOING THIS AS YOU NO NOT WANT TO DRILL INTO ANYTHING OTHER THAN THE COVERING.