The importance of well development for water supply wells has been known for more than a century.  Well development removes the fine-grained materials from the borehole, which helps restore the formation to pre-drilling conditions to maximize production of water (yield) and reduce the turbidity of the water withdrawn from the well.  The act of well drilling itself is a destructive process that damages the formation by compacting, smearing and forcing the clays into the borehole wall.  Many development methods have been used to restore the formation to its natural condition after a well has been drilled.  Attempts to remove the clays and drilling fluids have included bailing, air lifting (with compressed air), jetting with high-pressure water, over pumping and surging.  Of all these methods, surging using the surge block is the most effective method for developing a well.
Drilling formation damage can occur by compaction, smearing, and fluid invasion during the following drilling methods:

• Cable Tool/Direct Push
• Smearing of clays into porous zones
• Compaction of formation
• High borehole fluid head forces water into porous zones
• Augering
• Smearing of clays into porous zones
• Compaction of formation
• Mud Rotary
• Smearing of clays with drill bit
• High borehole fluid head forces water into porous zones
• Hydration of bentonite in porous zones
• Removal of gel cake from drilling fluids

Using the surge block method helps restore the damage that occurs from drilling activities.

All types of wells need to be developed. These include:

Surging occurs as the surge block is pushed downward (downstroke), which forces water at a high velocity and pressure out of the screen.  As the surge block is pulled upwards (upstroke), the muddy water is pulled into the screen and pumped out of the well.  This back and forth working of fines through the screen suspends the fines in solution for removal from the borehole.  Surging, followed by pumping the muddy water from the borehole, is the most effective combination for well development.