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28° Julii, 1927.]
and one who, had he been satisfied that this scheme unworkable, or was feasible, or undesirable, would at once have told you so with the vigour and the candour which characterises Sir Alexander Gibb's evidence on all occasions. But you cannot fail to have been struck, if I may say so, with the almost friendly tone of the cross-examination in that case. Instead of finding that one had a really hostile critic, one found, on the contrary, that one had a critic who was sympathetic to the last degree, who recognised the merits of the scheme but who offered some criticisms, as any engineer may offer on another engineer's scheme, or as any lawyer may offer on another lawyer's opinion, or a professional man on another professional man's work, or a doctor, best of all, where it has passed into a proverb that
doctors differ," but he did not offer them as destructive criticisms at all. What did he say? He said, "I am concerned with the Middle Level Barrier Bank." He said, "Your scheme may involve this, that at critical periods, of course only at emergency periods, but taking a limited period you may retain more water in the Washes than has hitherto been the case as a result of your working of the system, and my position is that, sheltered as we are by that bank, anything that puts a greater pressure upon it—and it is a little frail in parts -may possibly cause a breakaway, and have disastrous results. My criticism is not that your scheme is wrong, and that the method of administration proposed is wrong, but if you are going to subject that bank to higher pressure than has hitherto been the case I want you to bear in mind that view." Then when I put to him what were the proposals for the strengthening of the Barrier Bank, he said, "I was quite aware of that, but I was a little apprehensive when I heard you were going to use material scraped up from the bed of the river and use that upon the bank, and i am not sure whether that will be mud or clay." I put it to him, "Do you think Mr. Binnie will put mud on the bank? and he said, "Of course not," and the episode dropped.
But under this Bill it will be the duty of the new Board, when constituted, to maintain that bank because it will be necessary for them to do so as part of the scheme of the utilisation of this reservoir; this safety valve. What was
his other criticism? His other criticism was this: Take the stretch of the river from Denver Sluice down to the beginning of the sea training walls. He said: "I have looked at Mr. Binnie's cross sections there and considered his method of lining the channel." The channel was to be excavated you may remember and left with a rather broad slope hollowed out and levelled at the bottom. He said, "I have looked at Mr. Binnie's method of putting in a toe of stone and slabs at the side. That is work which I am not sure can be carried out in the way Mr. Binnie suggests. Having regard to the nature of the backing there I am not satisfied these concrete slabs would remain in position or that that would be the best way to carry it out." He did not offer any alternative. He recognised that work of that character must be done and he agreed with me that after all it was only a question of method. Of course the Bill does not put its seal upon any method; it merely entitles works to be carried out. It does not bind anybody to carry it out in one way rather than another. It merely says certain work must be done there for the improvement of that particular channel, and if, as I put it to Sir Alexander, it were found upon starting upon that work, as many engineers find, that there were some defects in the method Mr. Binnie proposes, of course you do not go on and complete your work on a fallacious principle and you adapt your engineering expedients to the circumstances you find. but no one is here to condemn the carrying out of work on that channel. Thit that channel should be treated in such a way as to widen it and improve the level of the outfall all are agreed, and the criticism was on the particular method Mr. Binnie adopts. You do not necessarily give your approval to that scheme by passing this Bill. You merely approve the carrying out of the works so as to secure a lower level and improve the banks.
Sir Alexander Gibb's criticisms will, f course, receive most careful consideration. Having been asked what he thought of the scheme as an engineer, at page 330 he said: "I think the scheme is quite a good one." Then I asked him the further question: "And if built will achieve its purpose." His answer was, "If built will achieve its purpose.' That evoked from me the involuntary comment," Nothing could be hand
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somer." When one parts from a hostile witness on a note of that sort, I think I am entitled to invoke the weight of Sir Alexander Gibb's evidence. criticism amounts to this: First, he says he is a little apprehensive with regard to the Barrier Bank. Next he says: "T am not quite sure of your particular method of dealing with a particular channel." "Very good," I said, "supposing it is found that we can do it better, we will do so," and Sir Alexander said, 66 Naturally you will." In carrying it out in a medium of that nature, it is naturally experimental. Therefore, I leave Sir Alexander Gibb. He told you the works were carried out on a good basis and if carried out will achieve their purpose. What is their purpose? The effective drainage of the Ouse.
That leaves me only one matter to deal with, and that is the Huntingdonshire opposition. Again, in the case of the Huntingdonshire opposition I count myself fortunate. You may recall that with their witness I went over the programme of works item by item, and found that I had in that witness again not enemy but a friend, not a critic but a supporter, and to item after item through the programme of works, he said, "Not only do I approve of that but I want it badly." Take the walls, one of the most important parts of this programme of works. There has not been a single witness here who has criticised that part of the work. Indeed, there has been complete unanimity before you upon the desirability of those works. There have been some suggestions, very properly critical suggestions, again to the method or efficacy of the method proposed, but as to the necessity of sea training walls every witness has agreed, and not only agreed but urged the necessity for work of that character. I took him by stages through the work and I found at the end that he was really a supporter of the scheme of works, subject to this, and quite an important qualification, that at one particular part of the works, this important part here where the Washes are between these two rivers these two artificial cuts-he was not satisfied with the scheme proposed. Further examination of his attitude reveals this: He is not satisfied with the method proposed, but he has no real challenge of the works themselves so much from the practical point of view as that he maintains, or
they maintain, that there ought to be further and other works included, and I think it really came in the end to be this: We are apprehensive that your programme of works involves the abandonment, or at least the deterioration of what has always been regarded as one of the keys of this situation from the days of Vermuyden to now, namely, the Hundred Foot River. Time and again witnesses for the County reverted to this idea of their apprehensions with regard to that River. Now I think I can demonstrate that those apprehensions are founded on a misapprehension. May I just recall to the Committee's mind for a moment the exact position, the exact régime at this part of the River, because I am now going to maintain that the only point of effective criticism which survives on the programme of works is criticism with reference to this particular part of the River. The scheme is very simple, and if one may be elementary for a moment one may look at it from this point of view. At Earith, above which the River is to a large extent, although not entirely, in its natural condition, a certain volume of water is delivered. Of course, owing to the erratic rainfall in this country different volumes are delivered. A small volume presents no difficulty. The large volume which comes down in flood is the problem. The works at Earith designed by Vermuyden or anybody else are designed to achieve one thing, namely, to get rid of the excess water coming down there, that is to say any excess beyond what the normal channel will contain. In the ordinary case where the land is steeper the rivers are generally able when they come down in spate to discharge themselves right down to the sea, owing to the rapid rate of the water, as you see in a Highland stream in spate, but in flat lands, where, owing to the level of the land-because without levels you do not get gradients -the rivers are enabled to get over their banks and dissipate themselves all Over the surrounding country. The natural expedient, even when you have a leak in your own house, is to stop the leak and put a containing wall and confine the river to the channel. But banks themselves, efficient as they often are, are sometimes not sufficient, and in this particular region the problem is exceptionally difficult because of the extent of the plain, the largest plain in Britain, over which this water is liable to inundate. Banks which in themselves are
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sufficient in other places to contain flood water are not sufficient here.
The second expedient is to accelerate the flow off. Vermuyden had a great idea which, like other great ideas, was very simple. This water takes a long time to get to the sea because it goes meandering along, encountering, as it will, additional friction and having less gradient because it is a greater distance. Then he had the great idea, let us short circuit that, and in that way diminish the distance which the water will have to travel, and with the addition of banks and what I may call the sweetening of the course of the River we will retain the water within the banks, and we will prevent the water surmounting those banks by giving it a quicker run off. I think I may say that that in simple outline is the whole scheme which has been always applied, and consistently applied, to this area. But so difficult was the problem here that even with banks and a direct access to the sea there was still an inundation. Neither of those two usual expedients was sufficient to surmount the difficulty here owing to the configuration of the ground, and this expedient was adopted here which, so far as I know, is unique. If and so far as the water cannot be carried away by the channels, this ingenious idea was worked into the scheme, namely, the two water channels with outer banks enclosed a large flat area of land some 5,600 acres in extent and enabled the use of the Washlands, as they were called, as a kind of (to borrow Sir Alexander Gibb's word) "safety valve.” It is yet a third expedient to safeguard this district. If and so far as the existing channels banked as they are will not carry off the water even sweetened and straightened as they have been, and there is still danger of inundation, there is happily here an expedient, the expedient namely of for the time being holding back some of the water, using the Washlands as a reservoir, and in that way preventing the overcharging of the channel for the time being by diverting some of the water from the channel and putting it into this very large cistern or bath which has been provided between the two channels. That safety valve is calculated to play a most important and useful part in the régime of the river, because it is always there, and, if and so far as it is necessary to resort to it, which, after
point; it can be dealt with there. have, so to speak, subtracted a certain amount of excess water, and that being at your disposal you are able to relieve it as and when it can be got away with the least detriment and the least interference with the flow of the stream. It is a third expedient which has been devised here, most ingenious, and, as has been shown, most effective.
Mr. Riley.] Is not it a fact that for four months of the year those lands have been pasturage?
Mr. Macmillan.] Yes.
Mr. Riley.] The utilisation of the reservoir more than in the past will diminish the use of that land as pasture.
Mr. Macmillan.] It would, but there is, as so often happens, a debit and credit side to the account. First of all, the Washlands are only really used for emergency purposes, and, secondly, as and when an overflow would take place
the Washlands by our proposal, although the water would be admitted more rapidly to the Washlands, we propose to achieve a more rapid evacuation. The Honourable Member's point, if I may say so, is quite a fair one, but, on the other hand, if you look at the scheme as a whole we do not think any greater detriment would result, in fact we think more benefit would result, from the régime proposed.
Mr. Riley.] May I ask, is there an objection on the part of those interested in the utilisation of the Washlands to the proposal?
Mr. Macmillan.] No; there is no one from the Washlands opposing us, so that is not an element here. In fact the absence of opposition is a feature of this Bill and a significant feature.
Let us concentrate a little upon the other part of the scheme, Mr. Binnie's scheme. Let us see the quantity of water and, if I may draw Sir Murdoch's attention to it, I am coming to the point he
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alluded to. Let us see the quantity. I find in the evidence I have the material. Mr. Binnie first of all gives us the area draining to Earith, the total catchment area. It is 747,000 acres, Question 350. Now there are no gaugings, and therefore it is not possible to tell with precision the maximum amount of water which at the highest flood would come down that river. We have no means of knowing that from records. Mr. Binnie in these circumstances resorted to the known facts of the River Thames, the catchment area of the Thames, and where there have been gaugings, and where it is possible to ascertain with more or less precision the amount of the yield of the catchment at the maximum flood. He uses the figure, which was one-fifth of an inch run-off per acre per day. Upon that point there was a little controversy with Sir Alexander Gibb; I do not think it is really very material for the present purpose. He said he would have taken one-quarter of an inch per day, but I do not think it is necessary to resolve the controversy between these eminent engineers upon that matter. The figure would have a certain result upon the disposal of the flood, but not sufficient materially to alter the scheme. May I take Mr. Binnie's figures because I only have his figures on the evidence. An acreage of 747,000, a run-off of one-fifth of an inch per day as a maximum flood. The result of that is to give you 6,200 cubic feet per second passing Earith. Now that is what Mr. Binnie has to reckon with. Pray remember that is a condition which, as he points out, may arise once or twice in 50 years, but he is taking the very extreme case, which is what you have to guard against, because it is inundation you want to prevent. There are 6,200 cubic feet per second coming down, how are you going to dispose of it, and what means have you at your disposal? Mr. Binnie looks at the situation and he says there are three things I have here: I have the Hundred Foot River, I have the Old Bedford River, and I have the Washlands; these are the means at my disposal, how shall I utilise them?
At this point I want at once to remove the misapprehension which has arisen with regard to the attitude of Mr. Binnie, or of the Promoters, to the Hundred Foot River. It seems to have been suggested that Mr. Binnie has some sinister intent with regard to this ancient, venerable and useful work, and
that he will watch with satisfaction the Hundred Foot River gradually_silting up and going out of action. Nothing
could be further from Mr. Binnie's intention, and, indeed, the use of the Hundred Foot River is an integral part of Mr. Binnie's scheme. You will recall when he told us he had 6,200 cubic feet of water per second to deal with, his very first point was, I shall use the Hundred Foot River for 1,500 cubic feet per second; that is to say, he takes the capacity of the Hundred Foot River and he says, "I shall utilise that to get rid of my first 1,500 feet." Then the important figure, the residue of 4,700 cubic feet, which was alluded to so often, was the residue he had to dispose of after utilising the existing Hundred Foot River to the full. Therefore so far from Mr. Binnie contemplating the Hundred Foot River is to go out of action, it is the first and integral part of his scheme that it shall be utilised. I think I see how the misapprehension has arisen, and I am most desirous of removing it, because if I thought this scheme contemplated rendering that outlet derelict I doubt if I would have allowed my clients to put me up to advocate it. The position is that this Bill contemplates capital expenditure on permanent works. That
is quite a different matter from maintenance. The maintenance of this undertaking will be entrusted to the Ouse Board who will be entitled, if a subsequent part of the Bill passes, to levy rates and obtain contributions, which money in their hands will be dedicated statutorily to the maintenance of this undertaking, the undertaking of which the Hundred Foot River is a part; and the distinction which I think has given rise to unfounded apprehension is that whereas this Bill contemplates capital works on the very dilapidated portion of the Hundred Foot River which is down at Denver Sluice below Welmore Lake Sluice, it is no part of this Bill to carry out works of enlargement of the Hundred Foot River. But the maintenance of the Hundred Foot River as it stands, and as a vehicle for the conveying of water away, is essential to the efficacy of Mr. Binnie's scheme. Let me vouch that if I may by one or two references, because the point is so important that I wish you to follow it. At Question 426 Mr. Binnie deals with this matter, and in the Third Day's proceedings I would ask attention to the pages round about there. I will postpone
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that for a moment because it comes into another aspect of it.
I think I may do it more intelligibly this way before I read the particular passages, if I just complete my explanation He proposes to utilse the Hundred Foot River as I have indicated; he assumes that it will be maintained; he does not propose to spend capital money upon enlarging it, as was suggested, improving and enlarging it in the sense of cutting out to the original contour-or nobody knows quite what the original contour was, but enlarging the channel.
"I propose in my scheme of work to omit any capital expenditure of that nature for two reasons: First of all, in the upper part of the Hundred Foot River above Denver Sluice in point or fact recent history has shown that the channel is deepening itself." That i proved from records, that the channel is actually deeper than it was before. Then he says: And I have this very serious point to consider that if I were to enlarge the capacity of the Hundred Foot River beyond what I am reckoning on just now as its existing capacity of 1,500 cubic feet of flood water, then by enlarging it and improving it what would be the consequence? I would admit the tidal water in much greater volume." This blue stream, the Hundred Foot River, is the tidal river. If we were to widen and deepen it right up to Earith the consequence would be this, that the tidal stream would come up with greater velocity and in greater volume, because everything you do here in the tidal part of the works to increase the efficiency of the outflow equally increases the facility of the inflow, and he gives evidence to this effect, that the result would be that any benefit you got from enlarging the Hundred Foot beyond what its present capacity is, would be counterbalanced by this, that the tide would actually rise at Earith to 13 feet instead of 9 feet as it is at the present moment. You would actually have a tidal wave coming up there, and at Earith instead of having a lowering you would actually have a highering of 13 feet, was his reckoning, in place of 9 feet, and you would, of course, have a much increased bankingup effect on a tidal stream whose inroad into the inland territory would be facilitated by the fact that the channel had been widened and increased in section. "Therefore," he said,
an engineering point of view I regard it as inexpedient to increase the carrying capacity of the Hundred Foot River. But I demur," he said over and over again-indeed he ultimately grew impatient in his evidence with the view that he had any sinister design upon this important outflow, and he was concerned to show it was essential to his scheme.
Let me complete my explanation, and then I will give one or two passages because it is so important that I think I should vouch what I say. He says, "I use that for my 1,500 cubic feet. what about my 4,700 cubic feet?" He says, "This Seven Holes Sluice which is the inlet to the Old Bedford River is quite ineffective now. I propose aiongside the Old Bedford River to place a weir 2,000 feet in length stone faced, and over that at 12.65 ordnance datum (which was to be the level). "The 4,700 cubic feet will find its way down there there being no sluice, Seven Holes Sluice having gone, and passing down the Old Bedford River it will go over the crest of the weir at 12.65 ordnance datum and will automatically relieve the pressure." Consequently the water will pour into the Washlands there inevitably when that 12.65 is reached. It may be said in criticism that a weir contrasted with a sluice cannot be controlled. That is perfectly true; no water goes over until 12.65 is reached. After 12.65 is reached all the water over that goes. But it has this great advantage which all automatic expedients have, that there will be no human equation. It must operate. Therefore whenever the water reaches 12.65 it pours over into the Washlands. But for some reason or other this did not commend itself to certain critics. Our concern is not whether the water is admitted to the Washlands by a weir or by a sluice, but that it shall be admitted to the Washlands; and if the mechanical equivalent of a sluice, with what, I venture to think, are the less advantageous attendant features of possible erratic maintenance of it is preferred to a weir, I say we are not particularly wedded to that, but we are concerned with the régime which we propose to institute of admitting the water at the rate at which we propose it should be admitted when the flood has reached that stage. We want to get that 4,700 cubic feet on to the Washlands as soon as possible, because by getting it on there instantly