The water supply for my house is a pump and tank drawing from an artesian well that was drilled about 70 years ago. We have noticed in the last 6-8 months that there is now fine sand and silt in our water. I have installed a whole house filter on the pressure side of our tank and it catches most of it, but a 3 month filter lasts me about 10 days at best before we notice a big drop in pressure and it must be replaced...at about $12 a pop. I am a ways away from the blacktop so it'd be nearly cheaper to have a new well drilled than have city water run to the house. Any thoughts? Strainer collapse? How to remedy?