LAKE ELLESMERE.

Press, Volume LXIX, Issue 20909, 17 July 1933, Page 10

LAKE ELLESMERE.

THE OUTLET PROPOSAL. PRACTICABILITY OF SCHEME DISCUSSED. . (SITI'I'A.LL.K ITHITTKM ro?. THS PKE33.) 11. It. is unnecessary further to criticise the incompleteness of the report, or emphasise the almost 'entire lack of definite data on which its assumptions are founded, for the report itself contains its own criticism. Mr Furkert in a foreword says : "But before the Government makes any decision to proceed with works of the nature indicated, I am of the opinion that further investigation is necessary." Mr Langbein himself says : "There are certain difficulties in connexion with the scheme which should not be overlooked, and it is desired again to draw attention to them." He then enumerated four uncertainties, connected with points of such vital importance to the success of the scheme, that they should, every one of them, be cleared up before any proposal to start work could reasonably be entertained. Yet the Progress League urges that work be started immediately on a permanent outlet to the lake at an estimated expenditure of £BO,OOO, and gives the public the impression that it is backing a comprehensive and detailed survey of the whole project, whereas, as its originator and his sponsor (Mr Furkert) clearly indicate, the report is nothing more than a somewhat sketchy preliminary investigation. As the value of the lake as a recreation standpoint, and particularly for its angling and shooting, is quite generally recognised, the icoort concludes with a reference to' this : "The opinion was sought of Professor Percival, Professor of Biology, Canterbury College, as to what effect the proposals would have on the fish and bird life. He expressed the opinion that a scheme which would do away with the periodic rise and fall of the lake would be advantageous. Also that a scheme providing a permanent outlet to the sea would not, in his opinion, be disadvantageous." In a comment on a letter which appeared in the correspondence columns of "The Press," over the signature of John MacCmie, Professor Percival said that his conclusions were the result of 18 months investigation of the lake.

Possible Widening of Outlet. Now let us suppose that the outlet did remain open to the sea, as the Progress League expects it to. It is true that the Professor's remarks were made in connexion with the whole scheme (reclamation and reducing the area of the lake to 10,000 acres), but it is quite fair to apply them to the scheme for a permanent outlet only, for the changes under that scheme are less than under the other. It is a pity that he did not give some of his reasons for his views, for the bald statement as made above is anything but convincing, chiefly because it implies a knowledge of exactly what is going to be the state of the lake after the outlet had been open for a number of years—a knowledge which I do not believe the Professor (or anyone else for that matter) possesses. Does the Professor venture to foretell what the opening to the lake will be'like in, say, 10 ■years' time ? And, if not. how can he have any data on which to form an opinion such as he has exDressed ? Should the shingle from the south all be held up by the wall for a long period, then the action described by Professor Speight may easily take place, and we may have an outlet a quarter of a mile wide, and the whole of the lake turned into an estuary like that at Sumner. This is neither impossible, nor even improbable, if the arresting action of the wall should prove as efficacious as its promoters claim it will be. And in that case, the landowners around the lake would be in a very much worse plight than they are at present, and the Professor's assurances small consolation to the anglers of that day. But supposing that the outlet should remain only a small opening, though I can sec uo possible reason why it should do so, is the Professor justified in assuming that the salinity of the water, in the lake is going to remain substantially as it is at present ? For this assumption is necessary unless there are going to be changes the extent of which is wholly problematical. This much can be said for certain: The lake water in the vicinity of Taumutu would become very much more salt than it is at present, and probably the increase of salinity will extend to practically the whole area of the lake. Should this increase be sufficiently great to kill out the lake weed (Potamageton), and that is quite possible, if not probable, then again we are faced with changes the extent of which cannot be predicted.

Insect Food on the Lake. Even the maintaining of the lake at a constant low level would have far-reaching effects, chief among which would be that it would greatly reduce the 'area of shallow water in the lake. This shallow water, with its very gradually sloping bed, which is periodically covered with water and uncovered as a result of wind action, is the haunt and breeding place of the Smoke Fly—easily the most plentiful insect on the lake—which in its laval and adult states is such an important item in the food supply of both birds and fish. Reduce the numbers of this fly, and it is inevitable that there will be a reduction in the numbers of the birds which feed along the shores of the lake, and also, it seems to me, of the silveries (Retropinna) in the lake, although Professor Percival does not apparently regard that as of any importance. It is true that of the shore birds—the dotterel, stilts, black-billed gulls, godwits and knots—only the last two are regarded as game, but the keeping of the lake at' one level will, I have no doubt whatever, also seriously affect the numbers of duck on it, though the Professor, if he is correctly quoted, does not think so. I believe that one of the most important factors in keeping up the numbers of the duck on the lake is the annual rise of the water. To a considerable extent the grey duck leave the lake in the spring to breed, returning to it with their broods in the summer and autumn. From February to May they augment the food they get on the lake by feeding on the stubbles in the vicinity, but for the winter months they are very largely dependent on the food that they can get on the lake itself. As the lake rises it continuously provides new shallow feeding grounds for them, enabling them to remain on the lake, which they would otherwise have to leave. Although the reclamation scheme for the lake has been temporarily droDDed. it is worth referring to in

case it crops! up again. Professor Percival, the report implies, does not consider that the reduction in lake area would affect the bird life on it. I have shot on the lake and known it reasonably intimately for 36 years, and as a result of the observations I have made in that time I am of the opinion that if any considerable reduction in area of the lake takes place, then there will be a reduction in the numbers of the clucks and swans on it, which will be, if not proportional to the reduction in area, at least of that order. The swans would probably be less affected than the ducks.

A National Asset. Here, then, in Lake Ellesmero, as it is at present, we have a national asset as a recreation ground, the value of which it is quite impossible to compute, but which is certainly very great, and which will increase as the population of the country increases. Is the community as a whole going to be any happier if 30,000 acres of the lake are turned into pastures and we produce so many more kegs of butter or bales of wool ? Ido not think so, and to those who do I would suggest that when Hagley Park was originally set aside, there must have been many who said that it was quite unnecessarily large, yet we use it all to-day; and so it may very well be with Lake Ellesmere in the future.

And now for the people who have lands around the lake and who were promised a permanent outlet. I have said that I do not believe that the present proposals will give it to them —I do not think the outlet would remain open. But if it did. then it must remain of just a nice, handy size to keep the lake at the level they want. It must not be too small or their lands will be flooded : it must not be too large or the lake will become tidal and the landowners' plight will be worse than before. Of all the sizes that the outlet may assume there is only one that would give the settlers the benefits which they are asking. And this is the size that the promoters of the scheme have, without discussion, and for no given reason, assumed the outlet will take. I can only say that they seem to have been animated by a wholly unjustifiable optimism.

PROPOSED DRAINAGE SCHEME. VISIT BY JION. J. BITCHENER. Tentative arrangements have been made for the Hon. J. Bitchener, Minister for Public Works, to visit Lake Ellesmere to make himself acquainted with the details of the proposed scheme for the drainage of the lake, and also to discuss, later, the matter with a deputation representative of those bodies interested in the scheme being carried out.

Mr P. R. Clirnie, secretary and organiser for the Canterbury Progress League, told a reporter on Saturday morning that the Hon. J. Bitchener tentatively had fixed Wednesday, August 2, as the date for the inspection by him of Lake Ellesmere. On the evening of the same day, at the meeting of the executive of the league, the Minister would receive a deputation from the league, the Ellesmere Lands Drainage Board, Lake Ellesmere settlers, and others interested in the proposed scheme. These arrangements were the,outcome of an interview he had with the Minister in Wellington last week. The Minister had promised to devote the whole of the afternoon to the inspection of the lake and the whole of the evening to a discussion of the scheme with the deputation. The evening proceedings would be of the nature of a conference, at which, with the aid of maps, the whole position would be explained. The Minister, as he (Mr Clirnie) had anticipated, had been following the reports on the scheme which had appeared in the Christchurch newspapers, and seemed to be personally interested in the matter. Unless something unforeseen cropped up, it was not likely that there would be any alteration in these arrangements.

An Aerial View. It was his intention, Mr Clirnie added, if the weather permitted, to arrange for the Minister to view the lake from an aeroplane, the Minister having expressed his willingness to do so. Mr Chmie was of the opinion that no better method could be adopted in order to get a general idea of the problem of the drainage of the lake and the necessity for something being done to prevent the periodical SSding of the valuable lands on its shores.