Exploding water mains an historic issue
WHEN rocks started falling out of the sky into Michael Lahne's backyard, the Walker St, East Lismore resident had no idea what was going on.
However, when Mr Lahne rushed around to the front, he discovered a burst water main which was sending plumes of water more than 15m into the air and onto the nearby power pole, soaking the electrical box, cutting his power and phone lines.
Apparently it's not an uncommon occurrence for the city, as much of the water mains and sewers are made form clay and cast iron and can be up to 80 years old.
According to Lismore Council's strategic engineer water and waste-water, Rod Haig, the older sewer pipes are largely clay and the older water system pipes are largely cast iron.
"Council has an ongoing program to renew existing water and sewer pipelines," he said.
"We definitely have an ageing system and so we prioritise where work needs to take place through a series of factors including mains break history, age (and) condition."
Mr Haig said over the next 30 years council is spending about $90 million on replacing and renewing sewer and water pipes throughout the Local Government Area.
"The sewer system gets replaced with PVC and the within the water system, it changed to asbestos cement and then PVC," he said.
"There are still some asbestos cement pipes in the water system, and these are decommissioned in the process of renewal. With water pipes, you don't get fibres like you do with asbestos sheeting, so the asbestos doesn't pose a risk in the same way."
A spokesperson for council said in the 2017/18 financial year it will spend $1 million on sewer replacements/renewals and $2.2 million on water replacements/renewals.
Council said works on Lismore CBD sewer main renewals took place between March and June, with $600,000 of works planned for this financial year and further renewals slated for the 2016/17 financial year.
Part of the issue stems from Lismore's brush with a deadly typhoid epidemic in 1892 and the area was gazetted as a sewerage district in 1901.
However, the Department of Works was slow to start the sewerage network and in May 1905, the plague broke out in Lismore.
Finally, by July 1906, Lismore's network of clay sewerage pipes was complete.
This means Lismore having one of Australia's oldest sewer systems, as many towns and cities did not begin building sewer networks until the 1920s.
The CBD sewer renewals will extend the life of the network by around 80 years, council said.