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Recently there has been some argument relating to the flood levels of the waters through this community. (Remembering this article was written in the 1980's) Whilst the large floodings of the area might be well spaced apart, and due in the main to a number of coinciding circumstances, nevertheless the assessed height of two metres is well within the range of previous flooding down past years.
Dates of the big ones, according to memories of some of the older folk and from what we might read, appear to have been in 1884, when people rowed boats about the Jonnell Park area. When they reached the sandhills that then lay behind the main street, tied them to the school building, which stood on the western side of the dune, and walked across to the shop at Wright's, and other businesses they wished to visit.
In 1927, at Easter, the flooding again approached this height and numerous photographs allow us to make some sort of an estimate of the height. One such photograph is of the Chapman family house. In anticipation, probably of such occurrences, it had been built on piers some three feet or better above ground level. During the 1927 flood our photograph was taken about the stage when rain had ceased and the sun filtering through the clouds again. The people are standing on a punt beside the Chapman family house, in which we are assured that the river waters were at least a foot (0.3m) above the floor level of the rooms. Thus we estimate that the flood level would be in the vicinity of eight feet (2.7m). Heavy rains in the inland country, from which the rivers flowing into the lake run, normally raise the river levels, but once they empty into the lake there is a tendency for the levels to drop as the water spreads across the whole area of the lake. But if the flow of water from the lake is lessened or ceases due to the entry of a rising tide, then the lake levels also tend to rise, for the incoming tidal waters exert sufficient pressure to turn the river waters back and raise levels. Should the tides be of extra heights, as does occur on occasions, or beaten in by high winds, the nor'easter being of extreme significance, rapid rise occurs.
In 1962, heavy rains brought water levels over most of the south-western portion of Tuncurry, there being several inches of water right across the Taree Street school playground during the afternoon. (This building in 1999 is now T.A.F.E.) This, the usual muddy brown river water, flowed out late in the afternoon. Later that night, the result of the rising tide, the river waters suffered a bank back and again the area was covered with water up to six inches deep but this time it was clear salt water forced across the area by the water pressures from the incoming tide, driven by a nor'easter and the river waters draining towards the lake.
These floods do not come often, but since the 1962 period several changes have occurred with the entrance to the lake, in that the extra lengths added to the breakwaters have brought them closer together, making the entry to the lake smaller in width; this of course concentrates the waters to a narrower channel. This has had the desire effect of causing a stronger wash-out on the run-out of the tide, and as a consequence a deepening of the channel. It has meant that during the roughly six hours run-in of the tide less water enters the lake, thus leaving the tidal level less than it was prior to the lengthening of the walls. (Oyster farmers were well aware of this as it made adjustment of the height of their racks necessary back when the walls were altered). How all this change will affect the flooding levels of the rivers and lake is yet to be determined as since the change there has not been a flood of any magnitude.
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