The Waterra Surge Blocks are great tools for removing silt and sediment from the bottom, sandpack and screen of monitoring wells. The SBD-25 surge blocks are designed for use with the D-25 foot valve, the SBD-32 surge blocks are designed for use with the D-32 foot valve. Each surge block has two differing sizes, one for 2" wells and the other for 4" wells.
