Thanks for the data, Spud, but where, exactly were these readings taken and how far in did they reach? If they were taken just inside the barrage then they tell us nothing beyond the fact that the barrages need repair. What we actually need is a set of simultaneous samples along a couple of transects from Tauwitcherie Barrage to the northern lake shore, and for at least four points in the water column from bottom to surface.

And we need the same along the Goolwa Channel so we know exactly how far these intrusions are getting. The basic geophysics of narrow mouth to the sea, small tidal range, single tide (if any) each day and resulting slow flow speed tells us that normal (non-storm surge) intrusions cannot reach very far before the tide turns.

To draw any conclusions for the rest of the lakes on the basis of data collected at the source of the leakage is not only unwise, it is gonzo science.

Lance as it says 1.5 KM upstream of Ewe Island barrage. Unfortunately now for cost cutting reasons they have withdrawn the monitoring stations at Currency Creek,Finniss River,Clayton,Stony Point and Point Sturt 7 km SE Milang.

On May 22nd. 2011 when spring tides coincided with an intense low pressure system and storm winds to 40 knots. This event caused saline intrusion up past Point Sturt and to Milang and Mulgundawa in Lake Alexandrina. From May22 to July 31 there were 4 similar events but from June 1 the majority of the barrage gates were closed limiting the amount of sea water inflow.

Thanks. If the barrages had been open during those storm events the tidal prism would have been much larger and the rapid inflow would have transported a huge volume of sand from the beach into the mouth that the slower and longer duration outflow would have been unable to correct.

This would have restricted the inflow during both normal and subsequent storm events but the same gradual buildup of sand would have continued.

We need to be very careful about saline intrusion data taken just after a major flood because the mouth is much wider than the norm, the storm surge inflow volumes are greater, and the saline intrusions also extend further.

This is the fundamental inconsistency in Marohasy's position. She is using post flood saline intrusion data to justify an action that will only be even partially relevant in the next zero flow event in 20 or 30 years time. By then the mouth will only be open through a narrow dredged channel which will deliver minimal tidal inflows, as was the case in the last drought. It is only an 8th order issue at best.

Lance

Water levels upstream of barrages dropped to about 0.4m (at low tide) in the last couple of days as a result of the increased gate openings.
This has brought water levels here down closer to natural levels with tidal fluctuations.
No storm, no real winds, no king tides just a normal high tide but salinity at HI Bridge shot up to 41,051 EC and Ewe Island 31,660 at 6am this morning.
Just another example of what conditions would have like naturally in the past.

It was good to see Media Watch clear up any remaining misconceptions about Marohasy last Monday night.
How many times does she have to exposed for what she really is and does, before people stop paying attention to IPA big business shills?
Leave her in the same bin as Carter, Plimer and co.