Tag Archives: water levels

Floods and water levels rising

 

When I walked  along bodies of water dammed on the Derwent River such as Lake King William, I remarked on the low water levels, showed photos of deep barren shores, and posted about the coming danger to Tasmania’s electricity supply.  You can refer to a range of posts for different views on this topic including the following examples: Tarraleah Canal No 1 walk – where is the water?,  Lake King William, The rocky shore, Looking for a place to camp overnight, Death and Lake King William, Rise and shine, Trackless under the powerlines, and Andrew Hughes has walked, rafted and canoed the Derwent over the past month.

Newspapers recorded some of the extremes; here is one of The Mercury examples.

Hydro Tasmania is the organisation which manages water resources  by selling power not only to Tasmanians but via an undersea link to Victorians and further afield on mainland Australia.  For a very long while Tasmania had an unusually low rainfall, then when the Bass Link failed at the end of last year, this meant Tasmania could not buy power from the mainland if in crisis.  Over half a year passed before the fault was repaired and in that time water levels in dams, lakes and the river dropped steadily. In damage control, as politicians and the community worried about the reducing water levels, Hydro Tasmania released the information that our State could survive and continue to generate sufficient electricity in the local newspaper with dams at an even lower capacity . Nevertheless failure for rains to fall, created a situation where massive banks of diesel power generators were installed.  The operation of these generators cost Tasmania millions of dollars. The photo in this article shows an area being prepared for generators, and then the next article shows the installation outside Catagunya Power Station.  Generators were placed in many locations.  This article shows banks of generators outside the Meadowbank Power Station;  this is the closest power station to Hobart and is one of many that operates using the water from the Derwent River.

The dry situation was desperate.  Cloud Seeding was being practised as an option to bring on the rain.

Eventually the gods or nature heeded the call and the heavens opened.  As winter approached, welcome rain poured and began to replenish our dams and lakes.  The rain was heavy and persisted so that the water levels improved dramatically.  In the process, many parts of Tasmania experienced severe floods.  Dramatic stories were released in the media . The Ouse River, which feeds into the Derwent River, was the site of the death of one man.

These were terrible days for many.

Now the climate seems has returned to some sense of balance.  Our glorious spring time, albeit with some hotter days than normal, has passed and summer has arrived.  We all hope for prudent management of electricity generating water resources and for intelligent planning for extreme events – which we know are now more frequent around the world. In this way, the Derwent River will remain a living and useful flow of water which poses little risk to affecting people, animals and the surrounding landscape.

The complex that makes up Wayatinah – posting 2 of 7

Wayatinah Lagoon

Having taken a turn off Long Spur Road, Andrew and I were the only visitors to this misted expanse of water on the 29 October 2015, the characteristics of which were almost total silence and an immense sense of quiet peacefulness.  I felt privileged to stand in such a serene environment, and smell the clean fresh air.

20151029_084702 Liapootah PS on hill in distance.jpg 20151029_084713.jpg 20151029_084742.jpg 20151029_084845.jpg

Watch the video.

A boat ramp, away from the infrastructure that accepts the water to be transported to the Wayatinah Power Station, ensures the safety of anglers from any unexpected water level changes.

20151029_084906.jpg 20151029_084829.jpg

Michelle’s aerial photo below gives some indication of the size of this Lagoon, and the way the river bed snakes away from it amidst dense vegetation heading towards Hobart.

PA280095 Wayatinah Lagoon.JPG

Unpredictable water levels

20150918_102136

This sign is located near Rayners Corner beside Glenora Road on route to Bushy Park.

Years ago a friend and I drove up along the Lyell Highway, and then took a track down to the river somewhere between New Norfolk and Gretna.

We walked across a gravel bed to a rocky scrubby clump edging the water.  For a couple of hours we sat on the river side with our feet swinging above the glossy glassy black racing water of the Derwent River, lulled by the sun. I remember the clear reflections of the dense vegetation on the other side of the river. It was a joy to see fish rising to grab an insect that had been flitting near the water surface. Clouds began to pile up in the distance and around that time I looked down and realised the water was nearly touching my feet. The river’s water level was rising. We clambered back to the other side of this outcrop and discovered, to our horror, a swirling and dramatic pour of water separated us from the river bank. In recent blog postings I have mentioned the speed with which the Derwent River travels towards the sea. That day was my first experience of its dangerous fast moving flows.

The river was rising as we watched. We were stranded on an island and we didn’t know how much water had been released upstream. This meant we didn’t know whether the island would become submerged. Within seconds we knew we had to try our luck and get back to land.

Quickly we cast our eyes around for a couple of suitable branches that could act as walking sticks, as balancing poles, so we could cross the raging torrent.  Each of us started the crossing with a balancing stick. I remember stepping into that cold water and finding how uneven the ground was. It was not a simple gravel bed rather I was trying to walk on irregular sized rocks that rolled when I was pushed onto them by the force of the water. I remember that it was important to tread slowly and to lean my body at an angle towards upstream to counteract the pressure to send me downstream.

When I started the crossing the water level was at the top of my thighs. The distance wasn’t far but the water reached around my waist and splashed higher as I approached the safety of the river bank.  Once out of the water, we felt exhilarated.  But we both knew the danger we had been in.  And similar signs to the one in the photograph above were not around.  Situations like this remind me of the powerful importance of local knowledge.