Designed to work with the Waterra pump system, surge blocks are tough thermoplastic donuts that press fit onto either a standard flow system WA-D-25 footvalve to accommodate 2" wells or a high flow system WA-D-32 footvalve to accommodate 4" wells. The surge block is designed to free up silt and sediment in the sand pack and screen, and breaks down bridging, drawing these particles into the well and then removes this material from the well.

Features
•  Effectively increases the outside diameter of the WA-D-25 footvalve to 1 7/8" in 2" wells & the WA-D-32 footvalve to 3 7/8" in 4" wells
•  Reduces the annular gap between the valve and the inside of the well screen to approx. 1/16"
•  Significant increase in the surging action of the footvalve - surge block combo