THE BRISBANE FLOOD NOTICE BOARD.

By G. G. Bond, Divisional Officer, Brisbane.

24th January, 1911

A Notice Board for giving information to the general public of the rise and fall of flood waters at the various flood warning stations on the Brisbane River and tributaries has been erected under the clock tower of the General Post Office at the main Queen-street entrance by courtesy of the Deputy Postmaster-General.

A careful scrutiny of the new board will reveal its essential features. The design was adopted from a diagram prepared and issued by the Hydraulic Engineer some years prior to the transfer of the Flood Warning Scheme, with the Queensland Weather Bureau, to the Federal Government, and consists of two diagrams.

Diagram No.1 gives representations of the river gauges at the Flood Warning Stations in the Brisbane basin, viz., Woodford (at the head of the Stanley River), Caboonbah (on the Brisbane River, just below its junction with the Stanley River), Lowood (below the junction of Lockyer Creek), Ipswich Pumping Station, Goodna (below the junction of the Bremer River), and Brisbane (Port Office gauge).

The heights of all the floods about which accurate information is available are clearly shown by means of black lines connecting the various gauges.

The most important feature of the Board is the metal slide which has been affixed to the right-hand side of each river gauge. An arrow, fitted with springs to maintain it at any desired position, and painted bright green, works up and down on each slide, being at the same time moveable on an axis. The purpose of the arrows is obvious, namely, to indicate the height of the water on each gauge-pointing upwards to the figures if rising, downwards if falling, and horizontally if stationary. An additional arrow, painted bright red, will be used on the Port Office gauge-slide to indicate (when sufficient information is available to warrant an opinion) the approximate height to which the flood waters are expected to rise in Brisbane.

The danger level is marked on the diagram in red against each station. When the flood-warning officer at, say, Woodford reports to the station next below that the water has reached 22 feet on the Woodford gauge, i.e., danger level at that station, and is still rising, it is the duty of the officer in charge of the flood-warning station at Esk to send out mounted messengers up and down the river to warn people resident on land liable to flooding. Similar action is taken by each successive station down the river to Goodna. Finally, the height at which each officer must begin sending flood reports to the stations below him, in accordance with his carefully framed instructions, is indicated on each gauge.

Diagram No.2 is of special interest and value to merchants and others whose places of business or residence are situated below the flood mark. It shows, in the form of a longitudinal section, the relative levels of certain wharves, floors, and streets, the surfaces of observed floods, and the approximate surfaces of floods rising to different heights on the Port Office gauge. When it is expected that a flood will rise to a certain height indicated by the red arrow on the Port Office gauge, anyone whose wharf or floor is shown on the diagram can, by following back the flood surface line, ascertain whether such a flood will reach his wharf, floor, or cellar, as the case may be. It would certainly be advisable for all those who do not know the exact height of their premises above low water datum to have the level accurately ascertained by a surveyor, so that full use may be made of the facilities offered.

The Notice Board has been erected in a very prominent and convenient place by the Commonwealth Meteorological Bureau at considerable expense, and, in the event of a rise in the Brisbane River, officers will be in attendance at the Weather Bureau, night and day, to receive messages from the floodwarning stations, the import of which will immediately be indicated by the green arrows. The public may therefore rest assured that the very earliest intimation of a flood in Brisbane will be afforded by the Flood Notice Board, and they are requested to bear in mind two things:

(a) The instructions to flood-warning officers (mostly police officers) are very explicit, and well understood by them.

(b) If no reports are received at the Weather Bureau, it may be taken for granted that the water has not reached reporting height.

It is hoped that a remembrance of these two points will cause all those interested in flood developments to refrain from making personal inquiries, either at the Weather Bureau or by telephone, but make full use of the Notice Board, thus materially aiding the work of the Meteorological Office, which is rendered abnormally heavy in times of threatening floods.