Canal lining, channel lining, swale drains, ditch lining, water conveyance, aqueducts

The mechanical and waterproofing properties of Teranap does not deteriorate from long term exposure to UV and weathering, making them the preferred option for exposed canal lining systems. 

Many years of use has proven that Teranap is a reliable canal liner for exposed applications. BGMs are the only geomembranes for which there is a specific standard written for their use as exposed canal liners (see ASTM D 2643).

Testing of Teranap laid more than 20 years ago in exposed canals show they keeps their water proofing properties for decades, with cracks failing to breach the surface layer let alone to reaching the geotextile layer that gives Teranap its mechanical properties. 

Teranap has high tear and abrasion resistance which is usually overlooked in design but critical to resisting dynamic forces present in flowing water. Consequently, most geomembranes are selected on tensile strength or puncture resistance which have minimal relevance in canal lining applications.

A common design approach is to select concrete which has a high upfront capital cost in the hope that, being concrete, it will last. It will last, but long before that it will leak. Long-term seepage prevention in concrete canals is unrealistic because concrete is inflexible and suffers failure from the ongoing crack/seepage/settlement cycle. Observe any section of the thousands of kilometres of concrete canals and channels in Australia and you will find two things - cracks and uncontrolled seepage.

When a concrete canal first leaks due to the usual mechanisms of shrinkage, cracking and settlement, it is rarely visible.  The first crack leads to seepage and changes in the moisture content of the subgrade.  This causes the settlement of the concrete and more seepage which leads to more cracking. This cycle happens over the entire length of the system, causing it to self-destruct over time.

Cracked concrete canals lose water and money well before the cracks became obvious. The canal owner has overcapitalised on a concrete canal which will continue to leak for years before it is repaired, preferably with the use of Teranap.  Teranap is a flexible solution for both new canal construction as well as concrete canal remediation – offering better performance at a fraction of the cost to install.

A more cost effective approach would be to build the canal with Teranap 531 at a third of the cost of concrete.  The savings can be used to place concrete over the Teranap in specific sections where concrete may be desirable, such as high traffic areas for vehicles or animals.