The construction and Installation of forty three (43) Piezometers on the Goronyo Dam Embankment were executed between November 5, 2015 and February 19, 2016. The forty three (43) additional Piezometers which were installed to complement existing and functional fifty two (52) Piezometers includes twelve numbers (12) each on the main dam crest and berm; six (6) on the main dam toe; four (4) numbers each on the secondary dam crest and berm; two numbers (2) on the secondary dam toe and three numbers on the saddle dyke toe. The Piezometers are essential instrumentation for monitoring the seepage of water through the dam embankment structure and essential components of dam safety monitoring. The soil materials of the embankment as well as the rip rapped berm surfaces presented great challenges to the drilling operations and installations of the Piezometers as the silty sand embankment materials were very unstable under saturation and were collapsing into the drilled holes frequently. Also the crest of the dam is too narrow to permit drilling with heavy equipment (rig) and digging of a mud pit. All these were overcome through adaptive drilling instrumentations and techniques which involve a combination of small motorized and hand drilling rigs alongside movable mud pit (developed by National Water Resources Institute).The mud rotary method of drilling was employed throughout using the drag and clay cutter bits except in the saddle dyke where thick ironstone pan was encountered and hammer was used. While the movable mud pit facilitated the mud circulations throughout the drilling operation. All Piezometers were installed at the prescribed locations.

Keywords: Piezometer, Dam, Goronyo, Crest, Berm, Toe