R655-11-10C. Piezometers

A. All high hazard dams as well as moderate hazard dams, at the State Engineer's discretion, shall include piezometers. As a minimum, piezometers should be installed along two cross sections of the dam, one of which should be at or near the maximum section. Each cross section should include piezometers at critical locations in the embankment and foundation. It is preferable to have only one piezometer in each hole; however, more than one piezometer may be installed in each hole if the intervening zone between the piezometer tips can be adequately sealed.

B. All piezometers should have a surface casing projecting beyond the ground with the surface casing adequately sealed. The surface casing should include a locking cap to prevent unauthorized access.

C. All piezometer holes should be logged during drilling and any pertinent information included on the as-constructed plans. As-built locations, designations and elevations of the top, bottom, and porous interval of the piezometers should be shown on the as-constructed plans.