The water puddle method allows technicians to identify and
locate potential leaks, faults or tears in a geomembrane
occurring during installation. It applies a geoelectrical
technique that harnesses the electrical insulation properties
of geomembrane materials.
A DC voltage is applied to metal roller that sprays water
across the geomembrane surface and a grounding electrode is
placed in the earth outside of the test site, creating a
difference in electrical potential between the roller and the
underside of the membrane.
If the roller passes over any faults sufficiently large for
the water to leak through the circuit between the roller and
the grounding electrode is completed, and a technician is
notified by their detection equipment.
As it only requires a thin layer of water to be applied
gradually to the geomembrane, the water puddle method allows
for technicians to perform tests with 100% coverage even on
extreme slopes and uneven surfaces, with a resolution capable
of identifying leaks and faults smaller than 1mm2. Groupe
Alphard applies the method as standardised by ASTM standard