Geosynthetic installations are primarily used to strengthen terrains and prevent them from eroding. They use layers of polymeric materials and clay to solve civil engineering problems. These products include geomembranes since the polymeric property of the material is suitable for ground stability installations. Geosynthetic products are highly durable and perfect for geotechnical, geoenvironmental dams, canals, landfill liners, landfill covers, etc.
Geomembranes are used as barriers to prevent liquids from leaking from landfills or ponds. Installers are very careful to keep this project safe and protected even from a little leakage if possible. Engineers do this to protect the water from contaminating the installations and cause more damage to the environment. Hence, water lance testing is a must. Installers do their best to prevent any contaminant from causing more damage to the environment. Leaking for example can result in erosion of the installation.
Geomembrane leaks can happen due to poor quality of materials, poor engineering installations, factory defects, accidents, and negligence. Water leak should be prevented before it causes major damage to the installations.
Aside from the damage caused by a water leak, general water lance testing should also be a priority to ensure the quality of water present in the installation or to remove contaminated water in the installation.
Geosynthetic testing is best applicable for locating geomembrane leaks where the proper preparations have been made during the construction of the facility.
What is Water lance testing?
Water lance testing is paramount in geosynthetic installations. This method is generally used when slopes are steeper but it can also be used in flat surroundings. It requires a water source and becomes less sensitive on sites with poor boundary conditions. The minimum sensitivity is a 1 mm diameter leak. A low voltage direct current source is introduced to the water sprayed above the geomembrane.
Water lance method or the water puddle method.
In this method, installers use a stream of water directed onto the liner. It does not require large volumes of water, and the water is continuously recycled.
Water Lance Testing Method is the most commonly used leak detection survey for new liner installations. It allows surveying on non-level surfaces and it is a preferred method for bare non-conductive geomembrane. In summary, a successful Water Lance method in a geomembrane installation must be completely done to avoid unnecessary failure and costly restructuring.