Ageing sewage plants in city raise a stink

LAUNCESTON may have to wait 10 years before it's flush with a best practice sewerage system that meets environmental standards.

Soon Ben Lomond Water will begin asking residents what they expect from a sewerage system, and perhaps more importantly, how much they are willing to pay for it.

This will culminate in the Greater Launceston Sewerage Strategy with a 10-year time frame to implement at an estimated $150 million.

The task is considerable, given the current state of affairs.

The Launceston metropolitan area is serviced by seven ageing sewage treatment plants, none of which meet the regulatory environmental standards all the time.

In contrast, Melbourne has one plant.

Launceston's largest is Ti-Tree Bend where effluent gets only secondary treatment before being pumped in to the Tamar River.

On a bad day, it barely gets treated at all.

The reason is Launceston's combined sewage and stormwater system, at that size an anomaly for Tasmania, which backs up the treatment plant after large rains.

Ben Lomond Water chief executive Andrew Beswick said separating a combined system, which was not uncommon in old cities like London, could cost up to $200 million and was an unlikely option.

Also, combined systems had their benefits because they treated containments collected by stormwater but receiving treatment plants must be "overscaled" to meet the need.

Ti-Tree Bend does not fit that description.

Ben Lomond inherited the plant in 2009 from the Launceston City Council, and is still removing a backlog of solid effluent from the sludge ponds.

While the Environment Protection Authority wants it fixed as soon as possible, Mr Beswick said the regulator was not burdened with pricing decisions.

"We have to balance that and if we don't, we put too much pressure on the consumer," he said this week.

It echoes recent comments by his boss, Ben Lomond chairman Miles Hampton, who called for a rethink on what was expected of the water reforms and in what time frame.

Mr Beswick lists, as an example, the need to spend more than $1 million to deliver fully treated drinking water to locations with fewer than 20 customers.

He said it was time to look at other options such as filtration systems or even rainwater tanks for households.

"You don't necessarily treat them fully ever," he said.

Such suggestions would probably bring a wry smile to the face of Lilydale residents who argued against a $7 million pipeline from Launceston to replace their Mount Arthur water supply last year.

It's drinking water projects like this one that have taken priority over sewerage upgrades - although Ben Lomond has been making gains at the smaller regional plants like Beaconsfield.

Mr Beswick said the looming sewerage upgrades in the Tamar and Derwent Valleys would be the most expensive ever undertaken.

In Launceston, it will result in fewer plants, if not a single super plant somewhere near Ti-Tree Bend.

In the meantime, Ben Lomond is about to spend $15 million on odour improvement at Ti-Tree Bend - the smells occur courtesy of the sludge ponds.

While this won't improve sewage treatment, Mr Beswick said long suffering residents would be breathing a sigh of relief.

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