Risk To Our Drinking Water !

Sydney and Wollongong are both fast growing Australian cities served by finite sources of drinking water. We rely on predictable rain to replenish those water levels and from time to time residents face water restrictions, as happened with a recent drought.

A past dry spell convinced the government to invest in a desalination plant that creates drinking water from sea water by removing the salt.  It sits idle when we experience normal rainfall and as storage levels fall it is only capable of contributing a fraction of the daily usage.  Science warns that we are gaining an added population density that exceeds the capacity of existing water storage to service the city needs.

The catchment area that collects that falling rain and delivers it to storage is precious and seriously protected by law.  In the past mining has been refused permission to tunnel under water catchments because of the fear of subsidence.  When cavities are created deep in the earth there is a long term tendency for the land above to subside and this opens cracks through which the water may drain away.  It is not unusual for this to occur twenty-five years after the cavities have been created.

That has long created an ongoing battle between mining interests and conservationists over extending long wall mining under water catchment areas.  Mining is permitted underneath housing land but subsidence is reduced by the implementation of restrictions on the type and weight of permitted building materials used.  The mines are also taxed to provide a fund for restoration where subsidence harms homes.

Now there are two mining applications before the parliament to extend long wall mining into catchment areas.  The Planning Department has given Peabody Energy permission to extend its Metropolitan mine long walls under Woronora reservoir and South32's Dendrobian mine will also be granted permission to extend under a Sydney catchment area.

The miners are adamant that this is safe and the applications were confirmed by the Independent Experts Panel on Mining in Water Catchments.  A recent report shows Metropolitan has no evidence of a connected fracture regime to the surface.

This is the usual battle between well paid mining jobs being maintained if existing mine facilities are extended.  There is definitely coal under those reservoir lands but if mining proceeds and the experts are wrong there is no possibility of rectification if a fault develops and the water drains away and reduces storage.

It is a fact of life that we know very little about the land beneath our feet and one of the basic essentials for life is a constant supply of water.  Any interruption to the water supply would be disaster for metropolitan Sydney.  Surely a basic on which we can not afford to be wrong  !