Tuesday, January 20, 2009

The Jack-up Barge (Self-Elevating Platform)

The jack-up barge, aka the self-elevating platform (SEP), is working just off Cape Solander to install the seawater inlet structures for the desal plant. The SEP is clearly visible from the coast as it is a mere 500 meters from shore.

There are two tunnels that connect the desal plant to the ocean. One tunnel lets fresh seawater into the plant, and the other carries the waste brine stream away from the plant and back out to sea. The tunnels are built into the bedrock under the ocean floor, and the SEP is drilling vertical shafts to connect the ocean to the tunnels below.

The SEP is a barge with four legs. It floats into place, and when it reaches the correct position, the legs go down to the ocean floor. Once the legs are anchored, the platform begins to rise up on the legs. This provides a stable working platform so that drilling works can commence. Drilling of the vertical shafts is a precise operation and cannot be accomplished from a barge that is bobbing around in the waves.

A similar SEP was acquired for the Gold Coast desalination project up near Brisbane several years ago. Apparently it was attacked by pirates on its voyage from Singapore to Australia. Fortunately we didn't have that problem with our SEP.

I am able to publish photos of the SEP on my blog as it is visible to the general public from the adjacent national park. I am normally not permitted to publish photos or other facts regarding the desal plant because I am governed by strict confidentiality agreements that go along with the project.
The other photos in this post are of the national park and is a mere 10 minute drive from where I live. There is heaps of great bushwalking along the rugged coastline. Enjoy the photos.