PURPOSE OF UNDERGROUND WATER MONITORING
- Helping for design pump system;
- Determining the efficiency of the pumping system;
- Early warning of flooding;
- Monitoring the level of lowering of underground water.
METHOD OF UNDERGROUND WATER MONITORING
- Underground water observation well is constructed by PVC pipe with an outer diameter of 60mm, perforated at a range of 4m to 6m from the bottom up.
- Drilling to designed depth and wash borehole with clean water.
- Installing the D60mm filter pipe into the borehole, continue connecting the pipe to the designed depth.
- Filling gravel around the pipe.
- Cutting excess length of pipe and making protection box.
Underground water level equipment: The water level in the standpipe or observation well is measured by a water level machine consisting of a probe, a cable or a ruler marked with mm or % foot, and a cable winch attached to electronic equipment.
The probe is dropped into the pipe until the light and buzzer signal touching the water. The depth lines on the cable indicate the water level.
- TCVN 8869:2011 “Method for measurements of pore pressures in soil”.
- ASTM D5092 “Standard Practice for Design and Installation of Groundwater Monitoring Wells”