Coal seam gas production is water hungry business. Millions of gigalitres of water are brought to the surface, removed from the coal seam in order for the gas to be extracted. Conservative estimates suggest coal seam gas wells could draw 300 gigalitres of water from the ground each year from the some 40,000 coal seam gas wells estimated for Australia. Once the water is brought to the surface, it needs to be transferred via a vast network of underground water pipes to large feed ponds on mining tenements.
Large Diameter PVC pipes are the most cost effective material to build underground water pipes to get water from the gas fields to the water treatment plants, often located more than 50 kilometres away. PVC pipes potentially offer a 20% cost reduction in building water pipeline infrastructure over PE pipes in sizes ranging from 500 – 800mm. PVC pipe is also the best option for distribution of treated water back to the environment after the treatment plant.
Compared to polyethylene (PE) and metal pipes, the relatively thin but strong PVC-O pipes have greater water volume carrying capacity and lower susceptibility to water hammer, particularly compared with steel and cast iron pipes due to lower wave speed.
Besides its cost advantage, PVC is the best performing, most sustainable and the safest option for water infrastructure