You need a ground rod. If your well supply comes in through plastic, then you don't even have a ground. Regardless, nothing whould be grounded to the water. In the past, water supplys were used for a convienent ground, but today more nad more, plastic is used in water systems. Every electrical service should have a proper ground rod, not the water line. In some cases one may not wven be sufficient. Contact a competent electrician.

Other places to check are any D.C. connections. For example if you have an alarm system grounded to the water, that will often cause damage much quicker than A.C.