River Training and Control on the Guide Bank System

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PRB-TP/153R

Technical Paper No. 153. Original Issue 1903. Reprinted 1931

RIVER TRAINING A N D CONTROL ON T H E GUIDE B A N K SYSTEM BY

Mr. Francis J. E. Spring, C L E .

CALCUTTA PRINTED FOR THE RAILWAY BOARD AT THE EAST INDIAN RAILWAY PRESS 1935.

Copies obtainable from — THE MANAGER OF PUBLICATIONS, DELHI.

Price Rs. 3 - 4 - 0 or 5 s . 6 d

Forwarded with the compliments of the Secretary to the Railway Board of India. Simla,

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1st July 1935. J

All rights reserved»

River Training and Control Being a description of the theory and practice of the modern system entitled m

The Guide Bank System, Used in India for the Control and Guidance of

Great Alluvial Rivers by

Francis J. E . Spring, C . I. E. L.C.E.. AND MAI. HONORIS CAUSA, TRIN. COL, DUBLIN; M. INST., CE.; M. INST. MECH. E.; MEM. AM. SOC. C.E., CHIEF ENGINEER IN THE INDIAN PUBLIC WORKS DEPARTMENT.

CALCUTTA PRINTED FOR THE RAILWAY BOARD AT THE EAST INDIAN RAILWAY PRESS 1935.

Copies obtainable from — THE MANAGER OF PUBLICATIONS, DELHI.

Published by ICE Publishing, 40 Marsh Wall, London E14 9TP. Distributors for ICE Publishing books are USA: Publishers Storage and Shipping Corp., 46 Development Road, Fitchburg, MA 01420

www.icevirtuallibrary.com A catalogue record for this book is available from the British Library ISBN: 978-0-7277-5199-7

© Thomas Telford Limited 2011 ICE Publishing is a division of Thomas Telford Ltd, a whollyowned subsidiary of the Institution of Civil Engineers (ICE). All rights, including translation, reserved. Except as permitted by the Copyright, Designs and Patents Act 1988, no part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying or otherwise, without the prior written permission of the Publisher, ICE Publishing, 40 Marsh Wall, London E14 9TP. This book is published on the understanding that the author is solely responsible for the statements made and opinions expressed in it and that its publication does not necessarily imply that such statements and/or opinions are or reflect the views or opinions of the publishers. Whilst every effort has been made to ensure that the statements made and the opinions expressed in this publication provide a safe and accurate guide, no liability or responsibility can be accepted in this respect by the author or publishers.

This Technical Paper, which issues from the Office of the Railway Board, India, is not an official publication; neither the Government of India nor the Railway Board are responsible for statements made OF opinions expressed in the paper. H. L. WOODHOUSE, Director, Civil SIMLA:

1st July 19S5.

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\ J

Engineering, Railway Board.

A U T H O R ' S PREFACE. For some years past., it 'has been my ambition to attempt a clear elucida­ tion of the subject of the following thesis. For in the course of much inspection of railways and bridges throughout India, I have found that, in the absence of some definite basis for the study of this particular phase of river engineering, the practice of it was growing up somewhat at haphazard; and it seemed that, unless what had been done up to date and the experience that had accumulated were definitely set forth for easy reference, there was a risk of either extravagance of first capital outlay on construction on the one hand, or, as the alternative, heavy recurring expenditure on annual maintenance, out of funds which otherwise might be applied in payment of dividends. But the opportunity of writing such a thesis did not present itself until the arrival of the final year of my 33 years' service with the Government of India, as an Engineer in the Public Works Department, when finding myself told off to report on the practicability of, and to produce a design if practicable for, a bridge over the Lower Ganges vide Chapters X X I I I and X X V and also finding myself in touch with evidence of the experience of many years, buried in thte Government record racks I obtained permission to unravel the records in question, and was given a recommendatory letter to all the Indian professional authorities likely to be able to assist me in the search for information. The result is the following chapters. And I avail myself of this opportunity to acknowledge the courtesy and kindness of the many engineers who have helped in the collec­ tion of information, and who have placed at my disposal the results of their experiences. 2. The scheme of the book is as follows. After a brief introductory chapter, which attempts to give an idea of the importance of the subject and to justify my venturing to pose as an authority in regard to it, a com­ parison is made between the Mississippi and Indian rivers of the class chiefly dealt with. The reason why the Mississippi has been selected for comparison is, that whilst in Indian and English professional literature there is a great dearth of reference to the engineering of big alluvial rivers, the Mississippi and its spills and their treatment have given rise to an immense quantity of literature, much of it written by men of the highest professional standing and ability. In Appendix X, I have given a list of so much of this literature as appears in the Transactions of the American Society of Civil Engineers. In Chapters 111, IV and V, T deal with river action, beginning first with a resume of Mr. R. A. Molloy's theory of the action of the Indus and rivers like it, as based on his experience of great continuous reaches of them, and passing on next to river phenomena as they appear to the necessarily limited view of the engineer whose duty it is to build and maintain fixed structures to which such phenomena are a source of danger. 3. The next Chapter, VI, is an important one. In it I show how extra­ ordinarily different are the sands of different rivers in their susceptibility to water transportation, and how work of a class intended to protect the erodible beds and banks of rivers may be designed with due relation to the fineness or coarseness of the sand concerned. Chapters V I I to X inclusive explain the principles, as I understand them, underlying the due design of the class of works which give this book its title. These works are the guide banks in India familiarly known as 'Bell bunds,' after their inventor Mr. J . R. Bell, M . I N S T . C . E . which are used now-a-days, practically to the exclusion of all other systems, for securely holding a vagrant alluvial river between the abutments of bridges and weirs built across them. The proper design of these structures, which may run to anything between 5 and 50 lakhs of rupees — say £30,000 to £3,00,000 or" from $1,50,000 to §15 00,000 — worth, for the guide banks of a single bridge, has a most important bearing not only on their cost, whether for first construction or for after maintenance, but also on the amount of trouble involved in their

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future inspection and repair. V The result of the considerations set forth in Chapters VII to X is the offer to the profession, for provisional acceptance pending accumulation of further experience, of a type design for guide banks, for use in the class of rivers dealt with. Plate X X gives the author's type cross section for the stone armour of such works. Tlhe object of the design is that such works may be so constructed, once and for all, that the annually recurring cost of their up-keep, and the trouble of their up-keep, may be reduced to a minimum. Chapter X I I deals with a subject but little understood, namely, the effect on other interests, riparian towns, etc., of tihe narrowing of soft bedded rivers, by means of guide banks at the abut­ ments of bridges or weirs. 4. The next ten Chapters, X I I I to X X I I , are devoted to a history, extracted with much labour from masses of official records, the accumulation of years, of tlhe training works of certain selected bridges and weirs. In these chapters I have endeavoured to show how the idea of the modern guide bank gradually grew out of a number of experiences, until at last it was formulated definitely and given practical effect to. Then I offer evidence which, as I read it, shows up the defects of the earlier guide banks, and gives tihe clue for their improvement, and for the design of new ones, on the lines laid down in Chapters V I to X. Chapters X X I I I and X X V show how I have designed the guide banks and depth of foundations for the projected Lower Ganges bridge, which, if undertaken, will be quite the most formid­ able work of its class that up to date will have been attempted. Eecognising that cost, unit rates and relative cost are very important matters affecting the design of bridges and training works, I have devoted Chapter X X I V to the extraction of such evidence on the subject as seems likely to be useful to bridge designers. For if, as somebody has suggested, " Engineering is the art of securing the highest interest on a dollar/' the cost consideration can by no means be left out of account. Chapter X X V I sums up the general line of argument and Chapter X X V I I makes some suggestions. Finally the Appendices contain some useful information, especially a list of some of the literature, on the subject not merely of alluvial rivers, but also on that of river and harbour improvement in general, which the busy man may find useful for reference. Indeed I assume that any one finding it necessary to deal with the expenditure of money on a large scale, with a view to dividends whether for the State or for private shareholders, will desire to read up as much as possible of the records of other men's experiences in the particular branch of practice with which he is concerned. 5. The following very picturesque description of a great Indian river, the Narbada, taken from Mr. T. W. Webber's book, T h e Forests of Upper India and their Inhabitants/' will be of interest as affording a fair idea of the magnitude of the erosive forces with which Indian River Engineers have got to contend:— 6

It is at the height of the monsoon that the grandeur of this mighty flood is properly seen. Then the banks, which are 60 feet high, are full to within a. few feet of the top, with a great rushing sea of turbid water. Viewed from the summit of what were in summer high cliffs, the river runs onward just beneath one's feet; and the whole landscape seems to be gliding westward, only the distant glue hills of Bhopal appear­ ing against the sky above the moving sea. Far out in the centre of the current a great line of floating objects goes along. Great trees torn up by the roots sail steadily, their heads and branches, limbs and roots rolling alternately above the raging torrent. Houses and logs of timber, the bodies of cattle and sambur deer, and even human remains, float away in constant procession carried by the relentless force of the waters on their voyage of many hundred miles to the ocean. What a stupendous force which is gradually levelling down the land and sinking it in the sea! The mass of water, a mile wide and 50 feet deep, moving along for days and months together, fills the mind with wonder and awe. * The sky is lurid with heavy rain-charged clouds, at times dis­ charging torrents of drenching warm rain. At times the thunder rolls, and flash after flash of vivid lightning rends the sky, and the surface of the torrent is whitened and lashed by the howling hot tempest.

6. The bridges whose safety it is the aim of this thesis to secure, form essential links in a network of some 26,000 miles of State-owned railways, which, at an average rate of £9,133 per mile, have cost £23,60,00,000. In

Ill

the year 1902 they earned £1,34,80,000 net. or the equivalent of a 4-92 per cent, dividend. During the last 25 years, their dividends have averaged just 5£ per cent, per annum — a fine record for so large an outlay. 7. The canals, the safety of whose headworks forms the subject of Chapter X X I I , with due reference to the suggestions contained in Chapters V I I to X, are part of a State-owned system of Irrigation which, though it has cost only one-ninth part of what the railways have cost, viz., £2,56,50,000 yet returns even a large proportional revenue, viz., 6-38 per cent. The State-owned and controlled canals of India irrigate 12,000,000 acres, on which is raised a crop valued at £2,40,00,000 or just £2 per acre, out of which the State collects £0073 and tJhe farmer keeps £1840. It will be seen that the value of one year's crop, grown by the help of the State canals — if only it could be claimed by the State for such a purpose would prac­ tically suffice, or very nearly, to cover the cost of the construction of the entire canal system of India. 8. I desire to reiterate here what I have said in paragraph 6 of Chapter I, viz., that when desrcibing the gradual growth of the engineering methods which it is the chief object of this book to explain I have frequently been obliged to show how that growth was delayed and hindered by some of the senior engineers of the Indian Public Works Department of between 15 and 30 years ago. I wish, however, at this early stage, to make it clear that I have had no thought or intention of applying adverse criticism to the attitude assumed by these gentlemen; feeling, as I do, that if asked to sanction any very radical departure from existing practice in such matters, I would probably act with no less caution than was exhibited in my own younger days by such men as Sir Guilford Molesworth, Mr. R. T. Mallet, and others to whom it fell to put the curb on us younger engineers who, since those days, have evolved the modern Indian system of river training now to be described. SIMLA:

1st December 190S. F. d E. SPRING.

I N D E X TO T H E No.

CHAPTERS.

CONTENTS OF THE CHAPTERS.

I

Introductory

...

...

I

Comparison of Indian Rivers with the Mississippi

...

...

4

III

A theory of cut-offs and avulsions

...

...

...

7

TV

The physics of alluvial rivers in general ...

...

...

11

The deep scour which endangers permanent structures

...

24

The classification of river sands

...

28

...

35

II

V VI VII VIII

...

...

..,

PACE,

...

...

The artificial narrowing of rivers, by means of guide banks The length and shape of guide banks

...

...

...

41

IX

The guida bank section and that of its armour

...

...

47

X

Construction and maintenance of guide banks

...

...

56

Depth of bridge piers as affected by river training ...

...

60

The effect of narrowing a river on other interests

...

...

63

XIII

Spur training on the Chenab river

...

...

67

XIV

The training of the Sutlej at Adamwahan

...

...

74

...

84

XI XII

XV

at Wazirabad

Denehy's groynes at the Lower Ganges canal head works

XVI

Training works for the Ferozpur Sutlej bridge

...

...

87

XVII

The training of the Chenab river at Shev Shah

...

...

90

The Gogra and Kosi training works

...

...

101

...

...

106

The training of four Brahmaputra affluents, and of some minor rivers ... ... ... ••• ...

110

XVIII XIX

The training of the Ganges at Garhmuktesar

XX

XXI XXII XXIII

...

...

117

Training works at Khanki and llasul canal head works ...

...

138

The author's proposed training works for the Lower Ganges bridge

143

XXIV

XXVII

The training of the Indus at Dera Ghazi Khan

The cost of bridging and training

XXV XXVI

...

...

...

145

The gauging of a great river in flood time

...

...

151

Summary of advice as to guide bank design

. .

...

155

Suggestion for an Indian Rivers Commission

...

...

161

V

CONTENTS. CHAPTER I.—INTRODUCTORY.

The application of the theories and practice dealt with in this paper is limited to certain classes of rivers The author justifies his coming forward as an authority on the subject of river engineering How this paper comes to be written The importance of the subject, as gauged by the mileage of the rivers affected, and by the magnitude of the expenditure involved The arrangement adopted in this book No adverse criticism intended of the engineers who delayed the introduction of the modern system of river training. CHAPTER IT.—COMPARISON OF INDIAN RIVERS WITH MISSISSIPPI.

Indian rivers compared with the Mississippi Mr. W. Starling's description of the Mississippi The Mississippi problem differs from that dealt with in this paper. CHAPTER I I I . — A THEORY OF CUT-OFFS AND AVULSIONS.

Mr. Molloy's theory and notation of river physics Mr. Molloy's type of an alluvial river and its action Irregularities of actual as compared with mean river slope Causes of irregularity of low water gradient Causes of irregularity of high water gradient Tendency of the bars in main channels to silt up, and of those in side channels to open out The results of a cut-off. Mr. Molloy's notation The causes and effects of cut-offs not always the same in different rivers Engineers of fixed structures ought to understand the causes of scour, so as to be able to provide againstl it. CHAPTER IV.—THE PHYSICS OF ALLUVIAL RIVERS IN GENERAL.

General description of the rivers under reference Comparative size of these rivers in the cold weather and in flood The meanderings of the rivers, and their increase in length as the sea is approached Extent of a river's meanderings, and the cause A description of what goes on during flood time The higher flooded areas tend to grow higher by silt deposition A description of "short-cuts, cut-offs, and avulsions Lawless action down­ stream following a successful cut off A description of what is called erosion How the inhabitants of the river bottoms are affected by cut-offs How the inhabitants of the river bottoms are affected by erosion. The extent of erosion The effect on the inhabitants of the river bottom lands, of the continual erosion and re-formation of their lands The extent of erosion of cultivable lands in the Punjab The effect of duration of flood on bed changes Changes of bed conditions during fall of flood Effects of fall of flood stage, on silt deposition and transportation First period of fall of river stage, when the supply of water from above is adequate The effect of duration of flow while the supply of water is adequate Second period, when the supply of water from above is failing A valuable series of observations of 30 years ago on the river Sutlej Deductions from the observations of 30 years ago on the river Sutlej More such sets of obser­ vations much to be desired A permanent state of stability rendered impossible by the alternations of high and low river stages How velocity varies with depth, even with the same slope Peculiarities of a low stage river A typical bit of an Indian Alluvial river The extent of scour in the bed of the Gorai river A suggested improvement in the order of the chapters of this book. CHAPTER V . — T H E D E E P SCOUR WHICH ENDANGERS PERMANENT STRUCTURES.

Local areas of hard clay, how formed Local areas of hard clay, how acted on by the river Water shallow as a rule opposite banks that are caving rapidly. But deep scour often found alongside banks composed of hard material Deep scour may be expected wherever a swirl is generated The action of swirls or whirlpools Swirls how caused, and the location of scour-holes The three classes of scour to be provided for. CHAPTER VI.—THE CLASSIFICATION OF RIVER

SANDS.

Great differences between river sands The mechanical analysis of river sands Some results of the mechanical analysis of sands Suggestion for the classification of sands Results of the mechanical analysis of some sands from the Indus and its affluents Great contrast between the sands of Madras rivers and those of the Indus and its affluents, and of the Ganges Precautions to be taken when making a mechanical analysis of sand

VI

The practical result, in cost of training wo*ks, of differences in quality of sand Suggested co-ordination of 'sand quality and stream velocity with depth of scour and design of training works Information about quality of sand and other matters ought to be sent up with training works projects The angle of repose of saiids of various rivers Futile attempt to derive some law from the angles of repose of sands The specific gravities of river sands A schedule of river sands mechanically analysed Thickness of stone pitching needed to protect sand surfaces, for various grades of sand and slopes of river A suggestion that the classification of the sand of a river should be an index of the permissible depth of its scour when narrowed.

CHAPTER VII.—THE ARTIFICIAL NARROWING OF RIVERS.

The class of river training works referred to in this paper — - The design of the pair of gorge walls, or guide banks, will now be considered from all points of view - — It is reasonable to narrow a river and even to contract its discharge area, provided it be allowed to scour out to a greater depth How a narrowed river provides for itself an increased depth, without appreciable afflux The increased depth which a narrowed river may be trusted to scour The evidence afforded by three recently narrowed rivers, in regard to the depth that can be scoured Evidence as to enlargement of bed section offered by the Ganges at Garhmuktesar Evidence as to enlargement of bed section offered by the Ganges at Allahabad Hence it follows that a bridge may be shortened, up to a certain calculable limit The extent to which narrowing may in practice be carried Practical considerations connected with the construction of the earthen part of the guide banks Steps to be taken for deciding how far a river may be narrowed between artificial gorge walls No existing bridges narrowed far enough, except perhaps one.

CHAPTER V I I L — T H E LENGTH AND SLOPE OF GUIDE BANKS.

The design of guide banks so far as their length is concerned The evils of making a bridge too long, and the advantages, in straight flow and deep flow, afforded by a bridge only sufficiently long The up-stream length of the guide bank depends largely on the breadth of the untrained river and on the radius of its worst bend The advantages of the still water areas behind the guide bank The advantages of small silting inlets and outlets Form of guide banks on plan. Mr. J. R. Bell's recommendations that they should approach each other at their up-stream ends The importance of symmetry, on plan, of the pair of guide banks Experiments, confirming the advantages of convergent guide banks The design, on plan, of the down-stream ends of guide banks The design, on plan, of the up-stream ends of guide banks The radius of curvature appropriate to curved guide banks Summary of advice given as to the design of guide bank on plan —— The straight guide banks at the Garhmuktesar Ganges bridge.

CHAPTER IX.—THE GUIDE BANK SECTION AND ITS ARMOUR.

The proper section for the earthen core of guide banks The most suitable section for the earthen approach banks Flood level liable to rise to an extra height „behind a guide bank Necessity for a stone covering for the exposed parts of a guide bank The size and quality of the stone to be used in guide banks The thickness of the stone on the guide bank slope The design of the apron dependent on depth of greatest scour Neces­ sity for ascertaining the depth below low water of maximum scour Why the Indian engineer can afford to use stone, instead of more perishable materials The foot-run cost of guide banks The importance of keeping up a plan for the recording of annual changes in the pair of guide bank aprons —— The minimum permissible thickness of the apron Effect of the specific gravity of the stone on its pitching qualities The undermining of the apron will probably, at worst, take the form of a steep cliff of exposed sand beneath the fringe of the stone Evidence on the subject of the slope assumed under water by the apron stone when undermined Recent evi­ dence about the slope of fallen aprons, obtained by probings of stone originally placed in a known position The author proposes a definite rule for the design of guide bank armour The chief functions of the guide bank apron The design of the apron when it must be laid below low water Relationship between thickness of slope stone and design of apron The principle of the impregnable head " A conception for a design for an impregnable head.

VH CHAPTER X.—CONSTRUCTION AND MAINTENANCE OF GUIDE BANKS.

The magnitude of construction arrangements for earthwork The magnitude of construction arrangements for stone The importance of realising how short is the time that is available Labour saving arrangements may or jnay not be necessary The arrangements for borrow pits The disposi­ tion of the stone on the guide banks The relative permanency of the old and the new training systems Permanency in the new system, how and when reached But certainty as to permanency relative and not absolute The best arrangement of service lines for maintenance purposes The guid* banks of certain rivers were commenced at their up-stream ends Th€ construction of guide banks in two seasons, how it should be done How to prevent the cutting of banks by wave lap during high winds. CHAPTER XL—THE DEPTH OF BRIDGE PIERS AS AFFECTED BY RIVER TRAINING.

Equality of scour in all the spans of a bridge is a relative matter, depending not only on velocity, but also on bed material The encouragement of scour to become deeper The prevention of scour from becoming deeper No such precautions can be trusted to justify shallow foundations. But they reduce the risks to which such foundations are subject Old-time wellsinking contrasted with that of the present day Present day well-sinking is comparatively cheap and speedy Heavy expenditure needed for loose stone protection around the old shallow well foundations Loose stone armour is wanted, as a rule, around the piers of existing bridges with com­ paratively shallow foundations How the loose stone round a pier auto­ matically covers the slopes of a sand cone, if properly designed and laid Large spans disproportionately more effective than smaller spans, for discharge purposes, when loose stone armour is used round piers The author offers a rule for the depth of pier foundations. CHAPTER XII.—THE NARROWING OF RIVERS AS AFFECTING OTHER INTERESTS.

Afflux te a matter of comparatively minor importance in India Large areas of land reclaimed from waste by river narrowing The danger and cost involved in keeping minor side channels open Cultivators' and Irrigation objections to the closing of flanking channels How flanking bridges may be made less dangerous High legal opinion on the claims of riparian inhabitants, for damages caused by floods alleged to be due to a narrowed bridge Another legal opinion on the same subject The importance of evidence in regard tQ alleged afflux, after narrowing. CHAPTER XIII.—SPUR TRAINING ON THE CHENAB RIVER AT WAZIRABAD.

In the following chapters, sketches will be given of the gradual growth of the present system of river training The Chenab-Wazirabad system is interest­ ing as a survival The composition and functions of Bund, Spur, and Groyne defined The river, at first trained to run through a two-mile bridge in a three-mile khadir, now trained through one-third of its original length The practical difficulties of the early river trainers Early diffi­ culties of site, and original methods, proposed or carried out. for training the river —— A description of the earlier bunds and spurs, and 01 the materials used in the making of them Early discussion in regard to the design of the abutments of the Chenab bridge at Wazirabad First proposals for reducing the length of the bridge Mr. Horace Bell's opinion in regard to . the comparative merits of the spur and the guide bank systems The entire cost of the Alexandra bridge training works to the end of 1902 The quantity and cost of stone placed around the Alexandra bridge piers The average annual cost of maintaining the existing spur system The effects of the floods of 1903. CHAPTER XIV.—THE TRAINING OF THE SUTLEJ AT ADAMWAHAN.

Training works not contemplated by the first designers of the bridge Serious defects in the location of the bridge The Government of India offer the Chenab-Wazirabad training works, 4£ lakhs worth, as a model ; but in reply get an estimate for 34\ lakhs Col. Peile's instructions to his staff, about the training of the river Col. Peile's further instructions to his staff The first estimate for training works, and the evidence that Col. Peile was beginning to apprehend the true principles of river training Description of the proposed training system, as put forward by Col. Peile The Govern­ ment of India's order, as to the extent and scope of the training to be attempted in the year 1874 The Government of India discourage all proposals for establishing anything permanent in the way of training works Mr. M. Rayne's opinion about the futility of using perishable materials for operations intended to have a permanent effect The recommendations of the Adam­ wahan Committee and their reception at the hands of the Government of India The completion of the training works in face of many difficulties The right guide bank as completed The left bank training works — The breach of the left training works in 1888, and how it was dealt with ^ The lessons derivable from Adamwahan.

Vlll CHAPTER X V — DENEHY'S GROYNES AT TJIE NARORA HEADWORKS.

A departure from the usual practice to be seen at Narora, on the Ganges, in the form of Mr. P. Denehy's spurs or groynes A description of the Narora training works Comparison of the Denehy system with the guide bank system The Denehy system on the down-stream right bank, below Narora weir —— The guide bank system apparently preferable up-stream of the, weir The cost of construction and maintenance at Narora The Denehy groynes show evidence of attaining to a condition of greater stability, as years go on The effect of the conditions of the river on the Narora groynes The cost of the up-stream works at Warora might perhaps have been better spent on a pair of guide banks Denehy's groynes the model for the Garh­ muktesar guide banks Suggested design for an up-stream impregnable head. CHAPTER XVI.—TRAINING WORKS FOR THE FEROZPUR SUTLEJ BRIDGE.

A description of the river Sutlej The original design of the Sutlej bridge, Ferozpur Mr. R . T. Mallet's original ideas as regards the training works Mr. Mallet went very near to inventing the modern guide bank system — Mr. J . R . Bell experiences difficulty with the spur system, which meanwhile has been approved in lieu of Mr. Mallet's originally intended guide bank system The failure of the spur system at Ferozpur, and the substitution in lieu of it of the guide bank system, after the floods of 1889 The later history of the Ferozpur Sutlej training works The author's recommendations as to the action to be taken at Ferozpur. CHAPTER XVII.—THE TRAINING OF THE CHENAB RIVER AT SHER SHAH.

The Sher Shah training works specially interesting as a departure from previous practice, and therefore looked on at first with disfavour Mr. R . T. Mallet's original design for the Sher Shah bridge Mr. R . T. Mallet's searchings after truth —— The first approved design for the training works was a spur system devised by Sir G. L. Molesworth, Colonel Home and Mr. Mallet The approved design of the training works Mr. J. R . Bell's proposal for a shorter bridge and for a pair of guide banks of the form now-a-days usually adopted —— Mr. Mallet rejects Mr. Bell's proposals, but in doing so shows incidentally that he realizes the importance of the apron principle Sir G. L. Molesworth, in holding the scales as between Messrs. Mallet and Bell, commits himself to a preference for the spur system After comparative estimates had been submitted, the Government of India pass final orders for a bridge of 17 spans of 200 feet, with spur training works on Mr. Mallet's design The author, as Executive Engineer, carries out the training works on the guide bank system, in ignorance of the orders that had been passed for making them on the spur system Sir Francis O'Callaghan inspects and approves of the Sher Shah guide banks, and condemns the spur system as unsuitable The amount of stone that was placed around the wells The amount of stone that was placed along the guide banks, and its insufficiency as proved by later experience The causes of the inadequacy of 300 to 400 cubic feet of loose stone per lineal foot of guide bank, in a river of the Chenab class The slips and losses which subsequently befell the guide banks, due to the insufficiency of its stone armour The movements of the river since 1892 have been such as to leave the left guide bank unattacked ; a thing not altogether desirable The first attack on the right guide bank in 1891, and the lessons derivable therefrom The events of the year 1893 A great gap or dip opened in the west approach bank, of area sffiucient to take one-fifth of the river's flood discharge —— Decision to close the dangerous gap, which was done in 1897 —— The loss of the head of the right guide bank in 1894 The Government of India criticize the proposals for dealing with the embayment at the back of the right guide bank, after the 1896 floods Ignorant attempts to wreck the guide bank system at Sher Shah, by the addition to it of swirl-forming spurs The cause to which the persistency of the river, in clinging to the right bank, seems ascribable Summary of the author's recommendations The probable discharge of the Chenab at Sher Shah Effect of the floods of 1903 on the right guide bank The Chenab seems to be straightening itself through the bridge. CHAPTER XVIII.—THE GOGRA AND KOSI TRAINING W O R K S .

The Gogra-Chauka and the Kosi bridges, as illustrating the advisability of starting guide banks at instead of above, the abutments The design of the GograChauka bridge near Bahramghat Training works of the Gogra-Chauka bridge designed at first on Mr. J . R. Bell's principles These principles departed from, to some extent, for certain reasons The accident to the left guide bank of the Gogra-Chauka bridge in 1897 The result of the accident was to change the plan of the left guide bank ATofes on (he condition of the left guide bank, as finally completed The right GograChauka guide bank, and the attack made on it in 1901 The Kosi bridge training works constructed on principles similar to those adopted at the Gogra, and with like difficulties The fending off of the threatened attack of the Ganges on the Kosi bridge The Bengal and North-Western Railway engineers justify their strategy.

IX CHAPTER X I X — T H E BRIDGE OVER THE GANGES AT GARHMUKTESAR.

The plan of the Garhmuktesar guide banks A general description of- the Garhmuktesar guide banks - — The section of their stone armour The embayment behind the left guide bank - — Miscellaneous notes extracted from the records CHAPTER X X . — T H E TRAINING OF FOUR BRAHMAPUTRA AFFLUENTS, . AND OF SOME MINOR RIVERS. *

Various estimates for bridging the four troublesome affluents Mr. F. B. Walker's evidence as to the instability of the four rivers Sir Guilford Molesworth's evidence as to their instability Mr. R. T. Mallet deputed to report on the river crossings Mr. Mallet's report, and his recommenda­ tion as to the Tista Mr. Mallet's advice as to the Dharlla, Sankos and Gangadhar The completion of the Tailway to Dhubri, including the four bridges The author settles the waterway of three of the bridges ^ — The effect of the floods of 1903 Evidence afforded by probings of the guide banks of the Tista Evidence afforded by probings at the Sankos and Gangadhar The application of the guide bank principle to some com­ paratively small bridges The Mahananda guide bank on the Eastern Bengal Railway. 1

CHAPTER X X I . — T H E TRAINING OF THE INDUS AT DERA GHAZI KHAN.

The threatened town of Dera Ghazi Khan Early attempts to keep the river away from the town The recommendations of the Committee of 1889 —— The making of the first stone-faced guide bank —— The decision to. extend the guide bank further upstream, on account of serious encroachment by the main river to the westward Observations in regard to the guide bank up to the end of 1895 Evidence in regard to the adequacy of the design of the apron — . - Discussion as to the best alignment for the extension of the guide bank Sir T. Higham's advice about the extension of the guide bank, and the decision. eventually arrived at — Colonel Marshalll and Messrs. Bell and Higham become converts to the Narbra system Progress of events between the ends of the flood seasons of 1897 and 1898 Lengthening and strengthening of No. 4 groyne after the floods of 1898 A graphic account of the final collapse of No. 4 groyne The events of the year .1900 ~-— Pro­ gress of events after the floods of 1899 until Mr. Dawson's arrival The work done by Mr. Daw^son and the wreck of his hurdle dykes —— Lessons derivable from the failure of the hurdle dyke attempt — "The hurdle dyke system long familiar in India The effect of scour on the hurdle'dykes, and the depth of scour to be found in the Indus The hydraulic j6t system . of pile driving - - - - - T h e recommendations of the Committee of 1899, in regard to foreshore reclamation, not systematically attended to - — F a u l t s in the shape, on plan, of No. 4 groyne head The section of stone slope considered by the author to be suitable for "No". 4 groyne head Design of the apron stone considered by the author to be suitable for No. 4 groyne head The inadequacy of the apron of No. 4 groyne head, as shown in the narrative of its failure The author does not pretend that he would have made a better job, at the time, of No. 4 groyne head, than was made by its engineers The position of Dera Ghazi Khan, in July 1903 The results of the floods of 1903 The author's suggestions as to future action The collection of information if action should be decided on Public opinion of the city of Dera Ghazi Khan Mr. R. D. Oldham's geological memorandum Mr. Molloy's views in regard to the physics of the Indus The objects of a policy of foreshore reclamation The requirements for putting such a policy into effective execution. CHAPTER X X I I . — T H E TRAINING OF THE CHENAB AT KHANKI, AND OF THE JHELUM AT RASUL, FOR CANAL HEAD WORKS.

The importance of effective training at Khanki weir on the Chenab Description of the Chenab near Khanki weir The original training works consisted of a pair of guide banks The Bhimber complication The addition of one Denehy's groyne to the Khanki training works A ten or fifteenlakhs scheme for Narora-izing Khanki at first proposed A three-lakh scheme decided on and carried out The author visits Khanki head works after the floods of 1903 General description of the Jhelum canal head works The guide bank of the Jhelum canal head works Different effects of weirs and bridges on flood gradients and river embayments. CHAPTER X X I I I . — T H E PROPOSED LOWER GANGES BRIDGE TRAINING WORKS.

The Lower Ganges bridge training works will be exceptionally heavy Design of the training works, and the section of their slope stone Design of the apron The arrangements for earth and stone will be very heavy The probable cost and unit rates of the Ganges bridge.

CHAPTER XXIV.—THE COST o r

BRIDGING *m>

T^AEfiNG.

In India* reiiafele uait rales for brkfeing ai& gen&tatt.v available Tb« aptirces of m i l r^es, and fee lase ol them Th# derivartion of the rates given in Af*p&Rdix IV Gayrbmuktesar bridge ami rates, &'—ti" gauge Tista bridge unit rates, metre gauge Unit rates of Dharila, Sankm and Gangadhar bridges, metre gauge Gogra-Chauka bridge unit rates metre gauge Rupnarain bridge unit rates, 5'—6" gauge All-over unit rates derived from the accounts of 11$ miles of bridging Unit rates composed of about one'eighth for pier rate and seven-eighths for girder rate Unit rates for guide banks. CHAPTER X X V — T H E FLOOD GAUGING OF A GRSAT RIVER.

The object of the gauging* of the Ganges at Sara The locality of the Sara gaugings The river slope near the locality of the gaugings The curves of velocities and depths A discharge curve deduced for the Sara gaugings Explanation of an apparent anomaly in discharge figures Curves of discharge antf flood height never alike in unlike situations Application of the principles; set forth in Chapter V I I to the design of the Length of the Lower Ganges bridge Judgment as to the probable extent of the enlarge­ ment of area of a narrowed Ganges at Sara The design of tee dfepth of the piers of the Ganges-Sara bridge, and its probable cost. 5

CHAPTER X X V L — S U M M A R Y OF ADVICE ABOUT GUIDE BANK DESIGN.

The object aimed at in the foregoing chapters The present chapter will sum­ marise the author's recommendations How far the narrowing of a river may be carried —— The length and alignment of guidte banks — - The curves of guide banks The guide bank slope stone The guide bank apron stone The maintenance of guide banks The cost of bridgrhg and training as influencing their design The appropriate curves for guide banks not yet an exact science The arguments as between straight and curved guide banks The author's reasons for preferring a curved guide bank. CHAPTER XXVII.—SUGGESTION FOR AN INDIAN RIVERS COMMISSION.

The benefits to* India of the alliance between Railways and Canals The absence of any organisation for recording experience or for original research^ in connec­ tion with ttie physics of great Indian rivers The; consequences of the lack of such organisation A suggestion for the appointment of an Indian Rivers Commission, in the interests not only of science generally, but ateo of Railways, and Canals.

xi I N D E X TO T H E PLATES. DESCRIPTION. No. I IA II HA III IV V VI VII VIII IX X XI XII XIII XIIIA XIV XV XVI XVII XVIII XIX XX XXI XXII XXIII XXIV XXV XXVI XXVII XXVIIA XXVIII XXIX XXX XXXI XXXII XXXIII XXXIV XXXV XXXVI XXXVII XXXVIII XXXIX XL XLI XL1I XLIH XLIV XLV XLVI XLVII XLVIII XLIX L

Map of India, showing rivers and bridge sites. A 50-mile reach of a typical river. Mr. J. R. Bell's suggestion for the type of guide banks. Mr. R. A. Molloy's type river and notation. Velocity curves, calculated by the Mississippi formula. The action of rivers at bends, showing abnormal scour. Illustration of spur action. Scour holes near the Narbada bridge at Broach. Sketch illustrating typical swirl or whirlpool scour action. Extent of erosion, as illustrated in the Narbada river. Sketches illustrating the prevention of scour by the use of loose stone. Sketches illustrating the development of the guide bank system. Type of attacks on bridge training works. Scour of bed after the narrowing of the Kistna river. The design of length of bridge for a given discharge. Diagram of depth of pier foundations. Sketches illustrating design of length of guide banks. Type of a severe bend attack on a guide bank. Training of the Kistna river below the great irrigation weir. Sketches illustrating the design of the curved ends of guide banks. Arrangements for the maintenance of guide banks. The training of the Ganges river at Allahabad. A diagram, giving the dimensions of guide bank aprons. The construction of guide banks ; and the dangers of flanking bridges. Chenab river, Wazirabad, as originally trained by spurs. Chenab river, Wazirabad. Spurs, bunds and groynes. Chenab river at Wazirabad. Training works in 1902. Sutlej river, Adamwahan. Training works. Sutlej river, Adamwahan. Sections during the floods of 1872. Ganges river, Narora and Rajghat. Denehy's groynes. A suggestion for an impregnable head, above Denehy's groynes. Sutlej bridge, Ferozpur. Development of its training works system. Sutlej bridge, Ferozpur. A recent attack on the training works. Chenab training at Sher Shah, as originally designed and as constructed. Chenab river at Sher Shah, before training. Chenab river at Sher Shah, since it was trained. Chenab river at Sher Shah, condition in 1902. Sections showing scour attack on Sher Shah guide bank. Gbgra-Chauka bridge training works. Gogra-Chauka bridge training works. Kosi bridge training works. Ganges bridge at Garhmuktesar. Plans of bridges over four Brahmaputra affluents. Probings of stone in Tista guide banks. Probings of stone in Gangadhar and Sankos guide banks. Dera Ghazi Khan protection works. Details of groyne heads at Dera Ghazi Khan. Plan of Chenab river, between Alexandra bridge and Khanki weir. Training works of some tidal creek bridges. Mahananda bridge training works. Lower Ganges bridge training works. Map of the Ganges near the site of the proposed Lower Ganges bridge. Diagrams of the Ganges discharge near the proposed bridge site. Arrangements for taking flood discharges.

Technical Paper No. 153.

THE TRAINING OF

CERTAIN

GREAT

RIVERS

IN

NORTHERN

INDIA,

SO THAT THEY MAY NOT OUTFLANK THE WORKS WHICH SPAN THEM. CHAPTER I. INTRODUCTORY.

I t may be as well to predicate that many of the statements and theories contained in the following pages have The application of the theories and praccomparatively slight application to ce?tafn X:ifofVvers. Indian rivers in the Peninsular area. They apply to some extent to the parts of the Narbada on the West coast and the Mahanadi on the East coast, where these great rivers are more or less alluvial, within 50 miles from tlheir d^bouehement into the sea; but they will be found of comparatively minor interest to engineers having to do with such rivers as the Kistna, Tungabudra, Godavari, Penner, Poniar and Coleroon in the South. These great Southern rivers and their thousands of miles of tributaries flow for the most part in fairly well defined valleys and between comparatively definite bluffs, and do not as a rule meander about in the apparently lawless manner of the great Northern Indian rivers, the engineering of which forms, the subject of this paper. The author ventures, nevertheless, to hope that a description of the line of practice now so generally adopted by engineers who have had to do with the extra-peninsular rivers chiefly under reference may — as indeed has already been tihe case to some extent — be found useful by their confreres in the South. He ventures also to hope that it may even prove of interest to English and American Engineers who — and especially the latter — may have to deal with problems somewhat similar to those that have been dealt with successfully m Northern India. A map of India, showing the great rivers and most of the places herein referred to, is given as plate I. e

p a p e r

i s

l i m i t e d

4 0

2.

In justification of his coming forward as an authority on the subject herein dealt with, the Author feels it author justifies his coming forward as necessarv to explain that his practical

The an authority on the subject of river engineer-

i .

.

y

f,,

.

*

,

acquaintance with engineering work on the large Indian rivers commenced on the Indus some 33 years back. Some few years later he had an opportunity of studying the vagaries of the Chenab while employed during the construc­ tion of the Alexandra bridge under Mr. H. Lambert; see pages 71-83, Volume LIV, Proceedings of the Institution of Civil Engineers; see also Chapter X I I I . Later again he had to do with the training works of the same bridge, originally 64 spans but since those days reduced by training to 28 spans of 145 feet. Again, in 1888-1890, the author bridged and trained the same river, the Chenab, 17 spans of 200 feet, under Mr. J . R. Bell, M.INST.C.E., on the first occasion of a great river being dealt with on ng

Chap.

I.

2

the system which he proposes to describe; vide Chapter X V I I , and also of July 20th, 1893, and ENGINEERING of September 7th, 1894. Soon after that, he bridged and trained the Kistna at Bezwada, 12 spans of 300 feet, vide ENGINEERING of July 3rd and 24th, 1896. Since then, in one capacity or another, whether dealing with the Godavari, Mahanadi and other rivers as Engineer-in-Chief of the East Coast Railway, or as Government Consulting Engineer, or while officiating as Director of Railway Construction, India, the author has had to do with the designs of the training works of many rivers of the class under reference, including, inter alia, those of certain troublesome affluents of the Brahmaputra, which will be dealt with in Chapter X X . 3. Recently, within a year of his intended retirement from the service , , . of_ Government, he-A. has U_T-• been Iput on How this book comes to be written. • i J J. x • J • special duty to write up this subject, in' connection with a projected bridge, probably of 15 spans of 350 feet, over the Lower Ganges. In preparation for the writing of this book he has visited a number of works, and the conclusions arrived at are the result of his study of them, and of their life histories as contained in the Government and other records that have been placed very fully at his disposal for the purpose. The following is a list of the places which the author has visited more or less recently:— ENGINEERING NEWS

A

t

XA

Places visited. River

Size of bridge. Number of spans.

Location.

Remarks.

Span in feet.

Allahabad

15

200

Do.

Garhmukhtesar

11

200

Ditto

ditto.

Do.

Rajghat

33

80

Ditto.

ditto.

11

250

Ditto

ditto.

15

350

Projected ; for Eastern Bengal Railway. North-Wcsterrt Stair Railway.

Ganges

••

Do.

••

Balawali

Do.

••

Sara

..

•.

Oudh and Rohilkh and State Railway.

Chenab

WaHrabad . .

28

134

Do.

Sher Shah . .

17

200

Ditto.

ditto.

Sutlej

Ferozeporc

27

145

Ditto.

ditto.

Do.

Adamwahan

16

250

Ditto

ditto.

Gogra Ghat

17

200

Kosi

Kursela

15

200

Ditto

Kistna

Bezwada

12

312

Madras Railway.

Narbada

Broach

25

184

Bombay, Baroda and C. J. Railway.

Tista

Kaunia

13

150

Eastern Bengal State Raihvay.

10

150

Gogra-Chauka

••

..

Bengal and North-Western Railway ditto.

Dharla

Mogalhat

Ditto

ditto.

Gangadhar . .

Near Dhubri

6

150

Ditto

ditto.

Do.

9

150

Ditto

ditto.

Sankos Gange*

Narora

Chenab

Kanki

Jhelum

••

Rasul

Indus

••

Dera Ghazi

..

Carpi headworks. Ditto. Ditto,

•• ••

Bank protection work onlv.

4. Before attempting to describe the methods now usually adopted for ,.