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RIVER FLOOD MENACE IN N.S.W.
Taming Savage Macleay Is
Big But Urgent Task
Although Australia's most destructive floods have scourged the Macleay River Valley every 25 years or so since white settle- ment, not one of them has been what the meteorologists call the "maximum possible flood."
Such a flood, the size of which scientists can only roughly estimate, could occur any time-yet the people of the Macleay, two years after their most recent flood, are still defenceless.
The N.S.W. Government has done nothing to protect the valley because Government officials have not yet decided whether the average annual flood damage is great enough to warrant the expense of huge flood-reduction projects.
'THERE is only one
way of taming the savagery of the Macleay River in flood, and that is by building huge dams many of them.
A practical geographer now studying the Macleay River's flood history is certain that the river could rise in a worse flood than the record disaster of 1949 (56 feet 9 inches at Tur- ner's Flat).
This geographer, who is mak- ing his study for the Federal De- partment of National Develop- ment and the N.S.W. Department of Conservation, said:
"An investigator last century questioned some aborigines liv- ing near Kempsey about the big 1864 flood. They referred to that flood, which was a mere two feet lower than the 1949 one, as a 'picanniny flood'."
A Sydney Weather Bureau spokesman said this week that a "maximum possible flood" could happen only when there wa3 a stream of moist, tropical air and a cyclone squarely over a river's catchment area.
During the 1949 Macleay flood, however, the low-pressure centre'was over Dorrigo. Rain- fall would have been heavier if the centre had been closer to the heart of the Macleay catchment
The short, steeply-falling Mac- leay River contrasts sharply with the long, comparatively level Lachlan (described in yesterday's article). The Macleay catchment of 4,581 square miles covers little more than half the area of the Lachlan catchment; but half its catchment area is more than 3,000 feet above sea level.
Water rushing down from these fastnesses runs only 300 miles less than one-third the length of the Lachlan River.
The Lachlan's flood waters spill slowly over its broad flood plain; the Macleay's waters roar down its narrow valley, sweeping past Kempsey, Frederickton, Smithtown and Jerseyville to the
Historical information about the Macleay floods is inadequate. But existing records do show that the river floods much less fre-
quently than the Lachlan. The ferocity of its floods, when they do come, dwarfs lhat of any other Australian river.
The Macleay has experienced a damaging flood once every three years since settlement. Six of these have been particularly damaging-those of 1840, 1864, 1893, 1921, 1949 and 1950.
The 8,600 people of the Mac- leay Shire will never forget Aug- ust 27, 1949. On that day a raging flood killed six people and swept away 53 homes and busi- ness premises.
It wrecked scores of other buildings and destroyed thous- ands of pounds' worth of trading stocks; destroyed 15,000 head of cattle, hundreds of pigs, horses and other livestock.
In that one quick flood, 1,500,000 acre-feet of water 100,000 acre-feet more than the river's average annual run-off swept down the valley at a speed
of 22 knots.
No Flood; No Work
Ten months later another flood (only six inches lower at Kempsey, the capital of the val- ley) swept down to .the sea.
Since then there have been no floods in the valley nor has there been the slightest sign of actual work to reduce damage by the next flood.
The Minister for Conserva- tion, Mr. G. Weir, made an im- plicit promise to the Macleay people when, in June last Jrear, tie appointed a Macleay Flood Mitigation Committee, under the chairmanship of Mr. C. K. Jacka, chairman of the Conservation Authority.
The committee's job, briefly, was to report whether it was "practicable to provide early effective relief against damage
and losses by floods in the lower Macleay district" and to deter- mine "the nature of the works required and the probable cost of same." The committee will also consider the hydro-electric pos- sibilities of any dams recom-
Representatives of the Depart- ments of Public Works and Con- servation, the Water Conserva- tion and Irrigation Commission, the Forestry Commission and the Soil Conservation Service-all of which must play an integral part in any flood reduction programme -are on the committee. Soil, water and forests are inseparable elements of the protective com- pound sought for the Macleay Valley.
All these agencies have been investigating the Macleay since June, 1951. The Flood Mitiga- tion Committee has held meet- ings with the Macleay River Joint Local Executive and the local drainage unions.
The R.A.A.F. has helped by taking aerial photographs of lands within 40 chains of the river banks. Officers of the De- partment of Agriculture and the W.C. and I.C. have inspected swamp lands in the lower Macleay region. '
The W.C. and l.C. has made hydrographie surveys of the upper river and has located several possible dam sites. The Forestry Commission is investi- gating whether or not selected timbered lands in the watershed should be dedicated as State forests. A district office of the Soil Conservation Service started investigating lands in the table- lands last November.
There have been many investi- gations, surveys and conferences. But, after 13 months, the Flood Mitigation Committee has pro- duced no report which could be the basis for a flood reduction programme.
This delay is understandable, though tragic. Flood Mitigation Committees are also investigat- ing the Tweed, Richmond and Clarence Rivers, al] i of which have similar, though less urgent, problems than the Macleay.
Analysis of data already secured on the Macleay has been further delayed by the transfer of staff to investigate important irrigation and food production problems in the. southern parts
The Macleay Valley is to-day the focal point of a vital debate which Government officials en- title "Dam Costs versus Benefits Therefrom."
All preliminary surveys indi- cate that the cost of substantially reducing floods in the valley
would be enormous.
Government officials are so
unwilling to mention a specific figure; but one official said that six flood reduction dams might have some noticeable effect on the Macleay.
Huge Total Cost
The estimated cost of Wark v.orth Dam, one of the eight dams planned for the Hunter River Valley, is £2,500,000.' On this basis, a flood reduction pro- gramme for the Macleay could easily cost at least £15 million.
But are floods likely to cause that much damage in the valley during the next 100 years? Just what degree of protection can the Government afford to give to the Macleay Valley?
A report last March by a De- partment of Conservation officer, while not answering these ques- tions, did say that the question of dam construction on the Mac- leay "should be related to over- all economies of flood effects in the valley and nothing has been done on this yet."
The Department of Conserva- tion hopes that a special survey now being made will relate dam costs to overall economies.
The Geography Department of the New England University College, Armidale, is carrying out this 12 months' project, which will involve the collection of historical and meteorological
By A STAFF
data about past floods on the Macleay and estimates and classification of all flood losses.
It is generally agreed that the
N.S.W. Government would be rash to invest heavily in flood reduction projects on the Mac- leay before the guidance of re- ports from the Flood Mitigation Committee and New England University is available. But those on the spot consider that some measure could well have been taken two years ago.
"Precious time is being wasted on visits, conferences and lengthy reports," says the 'Mayor of Kempsey, Aid. N. C. Long.
People To Blame
But the people of the Macleay
are themselves to some extent guilty of procrastination.
One office-bearer in the Mac- leay County Council admitted this when he said: "I suppose you've found out by now that everyone wants everyone else to do something about the floods."
. Our example of failure to do what could be done now is found in the fact that since the 1949 flood, the responsible authority, the Department of Public Works, has neglected the important job of dredging the tilt-choked Macleay River.
Before that flood, 500-ton vessels could dock at Kempsey. To-day, weeds grow around the Kempsey wharves and ships can travel only as far as Smithtown, 12 miles downstream.
"Every flood leaves silt which makes the river bed higher," said the Mayor of Kempsey. "Deepen- ing the river would greatly assist in flood mitigation. Spoil re- claimed could be used to build levee banks and refuge centres for cattle from flooded areas."
. Drainage unions, formed by local farmers, have shown no desire to co-operate with the
The lower reaches of the Macleay River showing the places mentioned in the accompanying article. The Macleay can flood more swiftly and savagely than any
other Australian river.
Government in flood reduction work.
There has been little continu- ous work on many of the estab- lished drains which carry water away from the Lower Macleay
Government officials believe that more efficient drainage, while not lowering flood crests at Kempsey, would free river flats of flood waters more quickly.
Two officials of Hunter River drainage unions addressing a meeting of the Macleay Flood Mitigation Committee in Kemp- sey last August invited members of the Macleay drainage unions to inspect the drainage works on the Hunter which are among the most progressive in Australia
nPHIS is the second of *? three articles review- ing the problem of river control in N.S.W.
The first article, which appeared yesterday, sur- veyed conditions on the Lachlan River; to-day's article deals with the Macleay River.
. A third and final article will examine the measures taken, and planned, in the valley of
the Hunter River.
So far, only one Macleay farmer has accepted this invita- tion.
. Then there is the question of town planning.
Kempsey, as long as it re- mains on a sharp bend in the Macleay River, can never be completely protected from
In every major flood, the river breaks its bank and rushes through the centre of Kempsey to enter its bed below the- traffic bridge. Levee banks might pro- tect Kempsey from freshets; but they would be dangerous in a major flood.
Some Kempsey people have already moved their homes from flood areas to high ground in West Kempsey, but there is no organised plan to move Kemp- sey to higher ground.
The nearest approach to this is a park scheme suggested by the Kempsey Municipal Council to the Department of Public Works and Local Government.
The Council wants to trans- form into park land that area of Central Kempsey which be- comes a second river during major floods. It has asked the department to pay half the esti- mated cost of £10,000 for land acquisition and improve- ment, and the department is still considering this suggestion.
. Finally there is the problem of flood-time communications.
It is pointed out that Govern- ment departments have done nothing to avoid in future the chaos which floods have pro- duced in the past. The Depart- ment of Railways considered using spans from the old Hawkes
bury River railway bridge to move the Kempsey railway bridge. But trains still use the old bridge which was broken in both the 1949 and 1950 floods.
The P.M.G. has not realigned telephone and power lines.
Kempsey still has no efficient flood warning system. But warn- ing stations, equipped with wire- less transmitters, will eventually operate at Bellbrook (40 miles upstream from Kempsey) and West Kempsey.
The pes. ¡mists may be right when they say that very little can be done about the Macleay floods. But that is surely no excuse for doing nothing at all about them.