Side Scan Analysis – Leichhardt Rowing Club (Iron Cove)

Side Scan Analysis – Leichhardt Rowing Club (Iron Cove)

This blog is a special request from Kristin who asked me to take a look under the Leichhardt Rowing Club pontoon with my side scan sounder.

It’s also the first outing for the new Humminbird Helix 10 SI G2N sounder so I’m still working on the settings but already the side scan clarity is an amazing improvement over the Humminbird Helix 5 SI Gen 1.

So let’s jump into some pictures. ***CLICK IMAGES TO ENLARGE***

Location 1: Rock shelf

This dark ridge looks like a rock shelf following the shoreline between the pontoon and the point at Callan Park.

Between the shelf and the shore we can see weed beds which take on a fluffy cloud-like appearance. It’s amazing the number of little rocks and holes scattered throughout the deeper water.

Location 2: Mystery object

Initially just looking at the map I only thought there were a couple of large rocks here.

However, when I downloaded the sonar files (the orange image) I saw I had driven over something fairly large.

I can’t exactly make out what it is.  What I can tell is that it’s:
– Hard
– Sitting in about 2.0m of water
– Partially buried in sediment and
– Extends 0.5m off the bottom

Location 3: The pontoon

The white line is the sonar bouncing back from the face of the pontoon.

We can see on the bottom quite a few smallish objects that appear to have dropped in the water particularly up the eastern end (use the dinghies on the dock for size reference).

It’s not to say there aren’t lots of other things on the bottom but the odd screwdriver dropped here and there is not going to show up as well as a pile of 10 screwdrivers.

There isn’t too much else around this area other than sand. Sorry Kristin, not as interesting as we thought.

Other Stuff

Elsewhere I found this submarine cable which extends from Sisters Bay to Callan Park. It looks like someone has dragged it with their anchor as it has some pretty impressive bends in it.

I also found this tightly packed school of fish out in the middle of the bay. There are some bigger fish lurking behind.

EQUIPMENT USED:

Sounder: Humminbird Helix 10 SI G2N
Range: 30m
Sensitivity: 10
Contrast: 12
Speed: 4
Boat Speed: 3kts

If you found this useful head over to our Facebook page and let me know which area you want scanned next.