Geoff Smedley

BEING mindful of the decomposition taking place in the Tamar basin now calls for nothing less than a radical yet sound solution to this serious problem.

The suggested plan is the culmination of a study into the many problems that have built up pertaining to these now decayed waterways, concerns about flooding and the enormous consequence these costly risks this issue alone holds. There are other items of concern just as important that have not been brought to the table for discussion or debate posing other dangers that our city faces in a new and totally unrevised future caused by our rapidly changing planet that now requires smarter and deeper thinking towards this very different future.

Australia is at crisis point in regard to fresh water, Tasmania also is rapidly coming under the same stress making it a priority that any deliberate wastage of this vital commodity should be deemed an offence. Forty cubic meters on average every second 24/7 is escaping from Hydro Tasmania’s Trevallyn power station alone, a crime to be ashamed of and should be addressed ASAP.

The concept plan submitted here is designed to address all these problems on a progressive scale beginning with the construction of a silt barrage to retain this water within the boundries of the city, creating a saline free body of water in which silt and sediment cannot settle, instead the offensive material is carried through a newly formed lake (Lake Batman), in suspension, then deposited beyond this silt barrier unable to return to the basin while creating a new Tamar estuary at Stephenson’s Bend where the North and South esk river now join the Tamar instead of the now totally choked Town point, the old Tamar estuary. All tidal effects would be removed from river frontages of the city allowing for stabilisation of shorelines within a reasonably short time, water tables within the now troublesome areas (Invermay and Inveresk) also would become stabilised to a far greater degree than any other time in history.

With a two kilometre canal through Heritage Park to divert the waters of the North Esk, particularly in times of flooding, these extreme flows would be diverted from the city providing a relief valve for the excess water to bypass Launceston and now scour the lower reaches of the river around Tamar Island and beyond removing the dangers now threatening the lower regions of the city, also eliminating the need for the proposed unsightly and costly levy bank experiment (saving more than $50 million plus). This new water artery would be a feature within itself giving rise to many ambitious schemes including the possible route for the much needed Eastern bypass, certainly able to provide a cost saving duel project operation that could well feed together.

The concept of a four meter high silt barrage/weir holds the key to the whole project. This unobtrusive structure, situated at Stephenson’s Bend across the Tamar, will retain a constant level of fresh water within the surrrounds of the city at all times; secondly it ensures that no silt can return to the basin once past this point; thirdly, the small amount of silt entering from the South Esk would remain in flocculation in the new desalinated waters of Lake Batman and be carried in full suspension beyond the silt barier, while the majority of silt carried by the North Esk is bypassed altogether by the new canal. The barrage itself contains within a self-operating loch allowing vessels of approved size to enter the city limits, also flood gates for full flood control and occasional flushing purposes where needed.

2

Distribution pipelines (three) from the northern end of the new Lake Batman would follow the river bed to their required destinations, (a) water for the proposed mill at Long Reach, (b) Launceston sewage and waste directly connected to the pulp mill’s waste pipeline beyond the mill itself and directed out to sea, (c) a third outlet would be available to deliver any silt build up that may occur from time to time with the need for only a small housekeeping dredge, similar in capacity to the one presently in use, and described as a manicuring pump but capable of managing the silt levels that may require attention on occasions.

These actions alone must be a major factor in presenting Launceston with a cleaner more respectable image while eliminating some of the noxious aromas that new pervade many parts of the city and surrounds.

The opportunity now also exists for a crucial second bridge to span the 65 kilometer long Tamar river. The means are now in place to provide a northern crossing from the suburb of Riverside directly to Mowbray on the eastern side using the barrage as patt of a support structure for a modern cantilever bridge of a size that will carry through to cover the future traffic needs. It could be suggested that this link would be funded by means of a toll, a practice quite common in the new world. Perhaps the biggest factor of all, this proposal has provision in place that should Hydro Tasmania still wish to sell the huge amount of fresh water required by the proposed pulp mill, should this be supplied via the Cataract Gorge, then taken from Lake Batman rather than the longer Trevallyn lake route, a very substantial flow would be returned to the now near dormant Gorge in Launceston.

The concept provided stretches far beyond an aid for a dying river, it is a bold transformation plan for Launceston bringing the 21st century a step closer to a city that has suffered many indignities in the past, moreover for a city that deserves an integrated plan of action that can re-establish it more in line as the northern capital once more, working to a plan for the future benefit of all Tasmanians, past and present, and above all the forgotten next generation. Tasmania may well be the promised land, but it is promised to everyone else and until such time the beaurocrats can tune in to the valid needs of the island’s residents, then the suffering will continue to fester.

The above plan is an ongoing development discussion concept that has no questions to hide, only sensible observations being attended to in a practical way in the best interests of all Tasmanians.

Geoff Smedley
Launceston.