supply , installation , and commissioning of 159 nos digital water level recorders ( vented/non-vented pressure type ) with telemetry , including protection box , fencing , security arrangements , with rain-gauge , flushing of existing departmental piezometer , digital water level recorders ( dwlr ) with telemetry , digital water level recorders ( dwlrs ) with non-vented pressure sensors & with barometric pressure correction with rain-gauge for individual station with measurement range specified in table 1 -- list of piezometer sites and 50meter sensor cable along with junction box and 5 meter signal cable and necessary accessories with battery operated data logger and telemetry system based on gsm & gprs , complete as per the technical specifications