I live in south jersey, Cinnaminson, everyone I ask locally says its just the water table. My question is wouldn't there be more of a sporadic change in the volume of water, even maybe go down for a day. It's the way it just keeps rising slowly that has me miffed...
Normally when the water table
changes, it is over a period of weeks or months. If there was a big storm then the water table might change in a matter of days.
The water table can vary from place to place even within a horizontal distance of a few feet, this may depend on different coarseness or fineness of the soil. When the water table is above basement floor level, an adequate sump pump and perimeter drain system lowers the water table to be below basement floor level at least within a few feet of the house.
When the water table is above floor level, then the sump pump system has to operate 24/7. If the water table is below floor level but above the bottom of the pit, then you can adjust the float higher so the pump is not so quick to come on.
It is possible for water to come up onto the floor at the far corner of the basement even though the pit is not full. So be prepared to adjust the float back down if you adjust it upwards.
It is okay if water remains in the pit all the time but it is more efficient for the pump to empty out the pit almost completely on each cycle.