MERSEY WHITE WATER REGIONAL RESERVE – BUSHFIRE DAMAGE UPDATE – 8th April

Featured / News/Events / Apr 11, 2016

As previously advised, the fires in January burnt out almost all the right bank of the Mersey from our get in point below Rowallan Dam and our get-out point above the lake.  The left bank is burnt out down to the slalom course below Washing Machine and then from Arm River junction.

As a result trees have fallen, some into the river.

Vehicle access is open to the river at our get in point below Rowallan Dam, our get-out point above the lake and to Berlin Wall.

Parks & Wildlife (the managers of this reserve) had done a lot of work felling dangerous trees in the area around the slalom course.  However the slalom course is still closed to access from the road.  The ‘Day Use’ area by the road is included in the closed area.  Parks had also cut up some of the trees in the river.

A Hazard Assessment of the river was conducted on Sun 3rd April by representatives of Tamar Canoe Club.  It was done from get-in to get-out, by walking the river bed with no flow.
The intention was to identify trees, branches and logs that were a danger to paddlers or restricted space in eddies.

A total of 20 paddling hazards were recorded on the day, at the locations indicated on the attached map. The severity of each hazard was assessed using the following criteria.  The severities are colour coded as indicated.
1 – No safe passage for kayak or raft (None found)
2 – Strainer/Sieve that is obvious and easily avoided by competent paddlers in an kayak or raft.
2+ => greater than 1/3 across channel (5 found, shown with red crosses on map)
2- => less than 1/3 across channel (10 found, shown with orange crosses on map)
3 – Obstacle in eddy (2 found, shown with a yellow cross on map)
4 – Overhanging obstruction (2 found, shown with a green cross on map)
5 – Tree may soon fall in river (1 found, shown with a blue cross on map)
(One recorded ‘hazard’ (#10) identifies debris on the bank that impedes foot access to slalom gates.)

Photos of 2+ hazards (red) and 2- hazards (orange) are attached.

Due to bush-fire damage to trees along the river the above situation may change as additional trees, branches or rope/wires at the slalom course could fall into the river.

The hazard assessment has been shared with Parks and they will cut up the obstructions as soon as practical.  This will often entail cutting trees into approximately 600mm long lengths and leaving them in the river bed to float out in the next water release (removal from the river is often impractical due to their diameter, weight and location). Those that don’t float essentially become wooden rocks. Where possible, lighter limb wood and saplings will be removed to the river bank. The hazard assessment gives Parks sufficient info to find the obstructions themselves.

Should working bee(s) be appropriate to remove off-cuts after Parks have cut up the obstructions, they will be organised in due course.  Working bees at the slalom course will also be organised.

Hydro advise that the flow from Rowallan Dam will be intermittent and largely unpredictable through April and May.   (It has been mostly off since 14th March.)

CANOE TASMANIA THEREFORE REVISES IT ADVICE AS FOLLOWS:
Any paddling from get-in by the bridge to get-out above the lake should be done only by appropriately skilled paddlers with experience on this section of river. You should proceed with caution and at your own risk (as you would anyway), and be particularly alert for new hazards or obstacles in what may have previously been your normal route down the river.

For paddlers finding any further hazards such as rope, wire, new trees or branches, please alert others (including via posts to the Derwent Canoe Club, Tasmanian Canoe Club and Tamar Canoe Cub flash sites and any of the club facebook pages. This will help other people avoid the hazards and we can also do something about managing new hazards as they arise and are identified.

Special thanks to Parks and Wildlife Tasmania for their work to date and upcoming work clearing the hazards, and all club volunteers who have helped on initial hazard clearing and hazard assessment.

John Borojevic
Chair – Canoe Tasmania Inc.

Upper Mersey Map - Hazard Loc 2016-04-03

1 Orng 20 Orng 19 Orng 18 Red 17 Red 15 Orng 13 Orng 12 Orng 11 Orng 9 Orng 8 Orng 7 Orng 6 Red 3 Red 2 Red