... and a map of the area of the lakes and the mouth showing the barrages:
|Murray mouth from the NW Source: Carbon Talks Blog|
|The Barrages Source: Murray-Darling Basin Commission 2005|
|Murray mouth - dredging in progress, July 2010 Source: Water for Good|
|Bathymetry - Lake Alexandrina (May 2009) Source: Department of Environment|
Bathymetric (depth) map of the mouth and upper Coorong.
|Bathymetry - Murray mouth & Upper Coorong (2010) Source: Department of Environment|
Bathymetric (depth) map of the lower Coorong, South Lagoon.
|Bathymetric map - Coorong South Lagoon (2010) Source: Department of Environment|
The tides at Goolwa Beach, off the map to the NW (actually from Victor Harbor) during April 2012, reproduced from WillyWeather and combined by me:
Note the individual tidal range increases from 0.5m on the 1st and 2nd up to 0.9m on the 7th, when there's a stretch of double-tides, with the lesser second tide increasing as the first tide begins to decrease. Two green "trough" (low tide) markers close together indicates two tides over 24-25 hours. The extreme tidal range is 1m, from 0.2m above datum to 1.2m. MSL is 0.65 (calculated) above datum. The resolution here is 0.1m, so the accuracy is +/- 0.5m (5cm). The NTC (BoM) flags Victor Harbor as having a range of 1.25m over a year as shown below:
|Tidal range around the Australian coast. Source: Bureau of Meteorology|
|Wind rose for Adelaide, SA Source: Bureau of Meteorology|
This shows that for about one third of the time, the wind is from the NE or N, pushing the sea back from the Murray mouth, assuming there's little difference between Adelaide and the mouth.
I'll add a few more charts later to demonstrate the parallels between Portland and Victor Harbor (and therefore the mouth) later, but this hourly chart for Portland gives a good picture of the annual tidal profile (though with slightly lower extreme tidal range). Note the lighter areas indicating single tides, the darker areas double tides, and the annual tidal profile and range. Month numbers on the bottom (x) axis are out-of-step because calendar months have varying numbers of days, though after May they line up quite well.
|Murray mouth at low tide, dredging in progress Source: StudyAdelaide|