272 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



[August* 



SKVKRN NAVKJAl ON IMPROVEMENT. 



(Concluded from page 24 '.J 



Abstract of the Eridence mi behalf of the tVorcesli r and Birmingham Canal 

 Cnmuanii a''aiiisl the Bill for improvinn the Severn, gieen before the Committee 

 of the House of Commons on the Hill, May 17, 18, 21, 24, 25, 27, Sf 28, 184-1. 



Mr. F. Giles, engineer, examined by Mr. Austin. — I am a civil engineer, 

 and have survevcif many rivers, liarljours, canals, and railways. I am ac- 

 quaiiiled with 'ihe Thames. Mcr.'ey, Medway, Ayr, and Caldcr, and many 

 other rivers ; 1 have also planned the construction of works with reference 

 to the .Severn : 1 have surveyed llie Severn with reference to ihe navigation ; 

 1 then particularly directed my attentiun to the drainage and scour of the 

 river, as f.ir as they were compatible with the navi|,'ation ; I surveyed the 

 river in 1837 with Mr. Rhodes' plans; 1 have surveyed it partially in the 

 present year. 1 am acquainted wiih the plan of Mr. Cubilt. Mr. Rhodes' 

 plan was for a ship canal up to Worcester, and a barge canal up to Stour- 

 port. [Witness then described Mr. Rhodes' plan.] That plan was not carried 

 into execution. I liave heard the whole of tlie evidence on the present plans. 

 My objections to it beginning at .Stourport are to tlie iiroposcd solid dams ; 

 I object to the principle of <lamming a river pomianentlv. With reference to 

 this river, it will decidedly obstnict the drainage, and be a great bar to the 

 navigation, when there is suflicient depth of water to pass ; and I think a 

 dillcrent kind of weir could be constructed that would afibrd the means of 

 passage m low- water season. In the first place, a solid dam must necessarily 

 raise The summer water level to the height of the dam; when the flood is 

 above the summer w aler level, supposing it to commence as the summer water 

 is now, not imp. unded (but you can pound it five, six, or seven feet) suppos- 

 ing the flood to commence rising above the artificial sum, if in the first place 

 Ihe flood rises five feet or more "above the original summer water, it must rise 

 it also five feet above the artificial sum of water, and so on every flood it 

 must increase with the rise of the flood in the same degree that the summer 

 water is to the flood. 



]jy Mr. Barncby. — >Iy answer does not refer to the river when bank full, 

 but of course it would fnl sooner. 



I5y Mr. Austin.— This plan would afi'ect some of the existing drains, par- 

 ticularly that wliich is made in the sewer at Worcester, and the drainage up 

 the country from the Salwarp to Ombersley. The drainage is about eiglileen 

 inches above the low summer wator. and of course the dam at Upton must 

 raise the water permanentiy in proportion to its height, and thus in flood 

 aflect the drainage; and that is not all, for the drainage of thi- gross matter 

 which comes from the sewers of large towns would be collected in pools, 

 which 1 lliink would be a very important matter. The Bcvere Island dam in 

 like manner would affect tlie drainage of the Salwarp; for if the water was 

 penned up below the Salwarp, it would be penned up in the Salwarp too. 

 ■fhe Salwarp drains an important district, which would consequently be 

 aficctcd. In my opinion, if oblique weir.s would ]iass more water than straight 

 ones, which I du ncjt think they will, it would not the less aflect the drainage 

 of the district. Whether oblique or at right angles the permanent height 

 would be Ihe same, and from that I apprehend the eflect to the drainage. 

 The deposit would silt upon the upper side of the ueir ; and I understand this 

 to be ihe eflect at the weirs on the Ayr and C'alder. where they have flood- 

 gates which would assist to remivc the deposit. 1 would have the weirs so 

 constructed as to have two, three, or more flood-gales, si.xty feet wide, so as 

 to be ojien whenever freshes come doH n ; 1 believe this would have a good 

 eflect upon the drainage. With any weir there must be a lateral lock, but 

 when the weir was open there would be no necessity for using the lock. I 

 can form but one opinion of the mode in which it is proposed to construct 

 the weirs— and that is, that they must wash away. I have never built one 

 myself but with solid masonry, and with a puddle bank to back it ; 1 believe 

 a fooling is absolutely necessary. I don't hesitate to say that it would be 

 most advisable to dispense with weirs between Gloucester and Worcester ; 

 I certainly think the experiment should be tried. I would put a weir above 

 Worcester, at Ihe upper end of the pool, opposite the '■ Dog and Duck ; ' I 

 would dredge up to this iioint, through the bridge at Woicester. I think 

 also the dam at Bcvere Island should be at the .Salwarp. This would render 

 it necessary to sink Ihe soil at Diglis lock, nothing more. The channel- 

 dredging in the river would necessarily lower the water at the wharfs at 

 Worcester, and it would therefore be necessary to dredge up to the wharfs 

 also ; this would improve the drainage at Worcester, it would be necessary 

 to have a dam at Worcester bridge, and to underpin the piers. I think the 

 improvements below Worcester should be executed, according to the exigen- 

 cies of the case, as they presented themselves during ihe undertaking. 1 

 would first proceed to narrow the river to a certain channel in the soft parts 

 by groins, the points of which would form one grooved channel down the 

 river. I should be able to asi eriain the force of Ihe scour as ihe works pro- 

 ceeded, and thus to regulate the extent to which 1 would apply the operation 

 of dredging. I should dredge at once in the hard shoals wilh an inclination 

 of four leet to one; I would propose to dredge six feet for the purpose of 

 obtaining five. 1 should not let my groins run into the river to the fuUextent 

 at first, liut should a3d to them, if I found it necessary to do so, to maintain 

 the depth. Deerhurst shoal being wholly composed of sand, it would be an 

 inteiminable task to attempt dredging alone, but with Ihe assistance of the 

 jetties or groins, I think ihe scour of ihe river would maintain ihe depth re- 

 quired. 1 think Mr. Provis' mode of throw ing in stones for the foundation 

 of his side walls a very barl one. 1 propose in forming my groins to use 

 stakes of larch, lined in the usual way with faggots. My groins will gene- 

 rally be about 120 yards apart. The quantity to be dredged I estimate at 

 500,000 cubic yards, which, at Is. per yard, would come lo £25,000; the 

 groins 1 eslimale at £28,500 ; and 1 have put down £G.000 lo be spent upon 

 Wcreeslcr Bridge, but I lliink that is much more ih^n will be requ red, lor I 

 believe £1,000 fur each [lierwill be quite suflicient. 'I'hen 1 have set down 

 £10,000 for contingencies (w)iich is more than 10 per cent.) so we will take 

 the total cost, in round numbers, at £70,000. 1 w as employed by the Wor- 



cester and Birmingham Canal Company to form a plan of my own for im- 

 proving the Severn ; this was after Mr. Rhodes" plan had been given up. 

 My plan went before Parliament, but it did not pa.ss. 



Cross-examined by Mr. Serjeant Merew ether. — I cannot tell you Ihe height 

 of the weir in my plan for improving the Seven;, but it was up to higli water 

 mark. I liave this morning had a model brought here, at the request of an 

 hon. member made to me yesterday, but I should like to speak with Mr. 

 Austin before I produce it. (Mere a question arose whether the model should 

 or should not be produced. Previous to the termination of the conversation, 

 it was understood that the Committee would re-examine Mr. CuUtt towards 

 the close of the investigation, to hear his answer to Ihe objections which 

 had been made against his plan.l Tliis plan was suggested by me to the 

 Worccser and Birmingham Canal Company, who paid for the surveys and 

 application to Parliament, and wlio intended to have carried out the im- 

 provement by a commission. The toll was to be 2d. per ton from Diglis to 

 Ciloucester. 'I have proposed another plan for the improvement, where the 

 toll lo be iiaid was Is. per ton. but that was for a Company, and not in con- 

 nexion with the Birmingham Canal Company. It was brought forw.ard in 

 opposition to Mr Rhodes' plan, and when that plan dropped my plan also 

 dropped. I agree wilh Mr. M'alker's regret— as expressed m his report— that 

 so 1 ille has been done towards the improvement of the Severn. I do not 

 think that Mr. Cubilt has sufticiently considered the drainage in his plan. 

 I know the situation of Lord Sandys' drain. I w ent down last Friday night 

 to open it and examine its level, and 1 knew the drain before. This drain 

 is about 100 yards above Holt Fle^t Bridge. The sewer at Worcester, which 

 1 mentioned yesterday, has been lately constructed, and 1 particularly men- 

 tioned it because it is' the principal one in the city. 1 was told the fall of 

 that sewer by the person who built it. 1 am only acquainted with the out- 

 fall of that drain. I do not believe the fall is 25 feet. The bottom of the 

 outfall of this drain is 18 in. or 2 ft. above the present low summer level of 

 the Severn, and the sewer is perhaps S ft. in height. 



By Mr. Godson. — The basin in Lowesmoor is at least 20 feet above the low 

 summer level of the Severn. ,,_,.. 



Cross-examination continued; I have no doubt but that there is a great 

 fall in that drain. I should think the entrance of the drain may be 20 feet 

 above its outfall. I have not heard of any public meeting of the people of 

 Worcester, in alarm at the eflect of the improvement on this sewer, but 1 

 have seen a gentleman on the subject. It was Mr. Williams, of the Distillery. 

 He resides on the opposite side of the river to wliere this sewer enters. 

 Where the water, in consequence of these artificial ponds, stops up the 

 moiilhs of drains, it must impede the drainage. I do not know the particular 

 eff'ect it may have upon this sewer, because I do not knoiv the fall, hut the 

 silt will have a tendency lo collect at the moulh, and will certainly be de- 

 posited at Ihe foot of the weir. The banks are about 16 or 17 feet above the 

 sewer at Worcester. There is not a considerable fall on the Salwarp a short 

 distance from its mouth ; there is only a fall of a few inches about a quarter 

 of a mile up the river. The height of the banks of the Severn near the 

 mouth of the Salwarp is about 15 ur 16 feet. I do not know the fall a quar- 

 ter nf a mile further up where the mill is situate. I still say that the valley 

 of the .Salwarp would be flooded sooner in consequence of the weir at Bevere 

 Island than it otherwise would be. I have never seen weirs constructed as 

 Mr Cubitt proposes to construct his. but 1 still think that his weirs would 

 not stand. Though I know Mr. Cubitt well, and know him to be a man of 

 great experience in these matters, I have no hesitation in saying that I be- 

 lieve him to be wrong in the construction of his weirs, both in Ihe mode of 

 forming them and the material to be employed (red sandstone from Holt and 

 itsncighbourhnod). I never heard of such a weir giving way, because I 

 never heard of .Mich a weir being constructed. I ilo not believe that Mr. 

 Cubitt's weir will be water-tight, for 1 do not think the sheet-piling will be 

 water-tinht; and 1 do think that the water leaping over the sheet piling 

 will blow' up the stone-work. I think a single row of sheet piles will not be 

 waler-tight. I have never seen a weir on the Taft. and I do not know that 

 there is one there constructed by Mr. Cubitt. 



By Mr. Hastie.— I have seen the weir at Hampton Court, but it is not 

 applicable to tho?e proposed to be constructed on the Severn, as it is formed 

 of strong piles, having sluice-boards, and I will undertake to say that it has 

 a solid foundation, cither of timber or masonry. 



Cross-examination continued.— The placing of rubble stone as an apron in 

 front of the sheet-piling will strengthen the weir, if ihe piling be water-tight. 

 I shall construct my groins with a slight inclination downwards. My groins 

 will be formed of willow stakes wattled ; they will be triangular, the base 

 being against the back of the river, and the apex running into the stream. 

 It is a very old mode of forming groins, and groins constructed m this man- 

 ner were formerly in the Severn at Upton and near the Ketch. They were 

 removed as a nuisance, because ihey canted the stream tc one side. 1 inean 

 to construct my groins so as to preserve a continuous channel as much as 

 possible. I hive certainly no doubt but that longitudinal walls would get 

 a more jierlectly continuous channel than the use of groins, if they could be 



t be the case by dropping in the 

 " ' " " 'or a 



^ ^,_ , Cu- 



buT's'proposarto 'taiie' advantage o'f "jie deepest parts of" the channel, but 

 prefer dredging a straight channel .along the centre of the river. Ilierc are 

 five arches at Worcester Bridge, and the centre one is 42 feet wide. Ihe 

 total ascent I have by my plan from Gloucester lo Worcester race-course is 

 6 ft. 4 in. The deepest water is under the centre arch and the one to the 

 left When the water is low, 1 do not think there is more than 3 leet under 

 Ihe centre .arch. I shall first dr.dge three arches, then a channel 60 leet 

 wide, through the sho.il up the race-course, and subsequently dredge up to 

 Ihe wharfs. When 1 have dredged thiougli Ihe arches and shial. 1 should 

 think all ihe waKr will be drawn from the wharfs, as it generally is at pre- 

 sent I h.ave been employed lor years by the Worcester and Birmingham 

 Canal Company. I do not know that, in consequence of the boats not being 

 able to unload at the Worcester quays, from want of water, they go into the 

 B irmingham canal to unload. 1 ha\e not calculated the amount nor the cost 



perfectly formed, which 1 think could not be the case by dropping m tl 

 stones, as proposed Ly Mr. Cubitt. No doubt it would be a great ev^il for 

 boat to strike the point of one of my groins. I do not approve of Mr. Ci 



