Water Well Pessure Loss Problem

[rcadjuster1]

What causes a shallow home water wells pressure to drop off and not maintain pressure while running irrigation system?
Pressure switch working properly set on 30/50
Verified pressure tank air pressure set at 28 lbs.
Drained pressure tank and no apparent problem with the bladder.

[LLigetfa]

Simple supply and demand issue. Demand is exceeding supply.