Permanent Solutions of Controlling Water Level in the Subgrade Sand
The permanent solutions of controlling water level would inevitably involve the introduction of sump pits with water pumps at various pavement blocks with blockage problem shown in Figure 49. The main difficulty in implementing the drainage scheme with water pumps is the availability of power line and space in the airfield pavement. It should be noted that there are limited grassing areas available for placing of the underdrain and sump pits for pumping in some of the pavement blocks. For areas with limited space, it may be required to provide underground piping connection to the adjacent block.