Have you ever read a development application where the land is said to be a level above AHD?

Do you know what AHD stands for?

The explanation appears below.

AHD stands for Australian Height Datum or Mean Sea Level (M.S.L.).

Well what is M.S.L. is a calculation which varies from place to place.

The Queensland Tide Book gives the following details about tide levels.

The Queensland Transport Department have a table which is called Tidal Heights Occurance Table.

This table set out in columns, range of tide heights, the number of tides that reach that height, the % of the total number of tides of that height, and the number of times the tide exceeds a particular range of tide height over 12 months.

Our Group was able to use the information in that table in making a Town Planning Objection when a developer claimed that the lowest point of a wetland was 0.6 AHD and that a drainage channel would leave the area dry pasture land.

The Department of Transport table predicted that land at 0.6 AHD receive tidal water 217 times a year and for about 19.25% of the time.

Our Group has a copy of the chart for the Brisbane Bar but we have been restricted on placing it on this web page.

Queensland residents can contact the Queensland Department of Transport for a table for their area.


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