The Globe. TUESDAY, FEBRUARY 26, 1878,

Globe, Volume IX, Issue 1240, 26 February 1878, Page 2

The Globe. TUESDAY, FEBRUARY 26, 1878,

THE announcement that Mr Clark has arrived in New Zealand, and will reach Christchurch by the first opportunity, naturally revives the subject of drainage, and it may be interesting to inquire into the present position of the question. It is not necessary to refer at Jeiigth to the early history of the controversy, Pur readers, of course, know that shortly after the Drainage Board was constituted, Mr. Carruthers was appointed Consulting Engineer, and in due course submitted a plan of drainage for Christchurch and suburbs. This scheme the Board accepted, and were about to proceed with it, wfyen a strong opposition began to be raised, whjteb finally resulted in the appointment t o.f a committee representing the ratepayers. These gentlemen held meetings in various parts of the district, at which resolutions strongly condemning Mr. Carruthers's scheme wore carried. A conference between the Drainage Board ap.6. the committee followed, and after 'ebnsiderabJ.o discussion the following suggestions representing the opinions of the committee wore adopted by the Board: —" That this committee ■ is of ppinioa that in any scheme of drainage ifi be suggested it should be a primary instruction that no excreta shall ,be removed by means of underground sewers, That no portion of the excreta shall be

allowed to bo placed in the Estuary. That before any scheme shall be adopted by the Board it shall be accompanied by an estimate of its cost. That this committee in making 1 these suggestions is anxious to add that it desires to see a system of drainage carried into effect which shall drain as largo an area as possible by gravitation, avoiding as far as possible the construction of pumping stations, only when absolutely necessary, connected with. a scheme of permanent underground drainage. And that after referring the plan for amendment to Mr. Carrnthcrs or to a local Board of Engineers, the committee recommends that the Board shall invite Mr. Clark or some other eminent engineer, to visit Canterbury and report upon such amended scheme." It was accordingly resolved that Mr. Bell should proceed to "Wellington to confer with Mr. Carruthers as to a modified scheme, and in due course a report was submitted. In it Mr. Carruthers defends, at some length, the scheme of drainage originally proposed by him. He deals with the various suggestions of the Committee of Ratepayers seriatim. It is not necessary to summarise his arguments in favour of removing watercloset excreta by means of underground sewers; or his reply to the objections to placing the same in the Estuary. "Whatever opinion Mr. Carruthers may have on these points, the Board have pledged themselves that neither shall be adopted. The other suggestion of the committee, that they desire to see a system of drainage carried out " which shall drain as large an area as possible by gravitation, avoiding as far as possible the construction of pumping stations, only when absolutely necessary connected with a scheme of permanent underground drainage," is discussed at some length by Mr. Carruthers. He points out that when he recommended the two pumping stations he was not aware that the present outfall drain was so badly built, and the Board having condemned it the Consulting Engineer is enabled to modify his scheme so as to do away with pumping. He takes great exception to the second half of the recommendation we have just quoted, maintaining that it practically recommends that a system of surface drainage should be adopted. We do not think such a construction can be put upon the words, and read in the light of the remai'ks of the individual members of the deputation, they convey to us a different meaning. Mr Ollivier said "as ratepayers they would agree to a system of surface drainage in conjunction with such underground drainage as might be necessary to carry off the sewage, and might be recommended by the Board of Engineers. Dr. Frankish stated, " That what they meant by ' surface' drainage was that as large an area of the district as possible should be drained by gravitation." Perhaps the members of the deputation were not quite decided in their own mind as to the nature of the drainage they wanted. At any rate they practically got the Board pledged not to carry out the main features of Mr. Carruthers's scheme; for excreta is not to be removed by underground sewers, and, consequently, it is not to be carried to the Estuary; and a careful estimate of the work has also been submitted. What then will Mr. Clark have to do when he arrives here ? In terms of the agreement between the Board and the Committee of Ratepayers, he will have to report upon the amended scheme of Mr. Carruthers. That scheme is summarised in his report as follows :

1. That I do not think any system can be designed which would fully serve the town and suburbs, and cost less than that I have submitted to you, but that it is unnecessary to complete the whole at once. A great deal of the sewers would in any case not be wanted for years. The arterial sewers of the system would oost £65,000 with the present outfall, and £129,000 with a new low level outfall. Seeing that the present outfall sewer is so badly constructed that it will probably have to be rebuilt in a few years, I think it would be better to indertake the more expensive scheme at once.

2. I think any system of sewers which are properly constmcted to carry ordinary sewage may be allowed without any change to oarry watercloset dejecta. The Board do not propose to allow waterclosets to be adopted, but this will have no irfluence whatever in the design of the sewers.

3. The punping stations originally proposed were only adopted because the expense of avoiding tbm was too great. Seeing, however, that in a few years a large expense will have to be incurred to rebuild the present outfall drain, I recommend that the extra expense be inciured at once. 4. The smaller branch and pipe drains may be all left out for the present. _ The main arterial drains will greatly improve the health of the town, and will relieve the Hooded districts where at present fever, diseases, &c, are very prevalent, and from time to time new sewers can be added where most urgently required. If we understand the above passage correctly tho modified scheme of Mr, Carruthers proposes a system of drainage which will carry off sewerage by a series of underground sewers and pipe drains, the main arterial ones alone to be constructed at present. It proposes tho building of a new outfall drain at a loAver level than the present ill-construeted one, thereby doing away with the pumping stations which formed a feature of the first scheme. He maintains that his system is as near an approach to surface drainage as is admissible in a town. To carry off the drainage of ihe houses there must be a fall of 1 in 50, which necessitates an underground sewer in the middle of the street at the Very commencement of an attempt to remove house slops, &c., and the necessity of maintaining a proper velocity of flow in tho sewers increases the depth, He does uqt propose to separate the rainfall from tho sewerage, such a plan being costly and ineffectual. In fact, at the present time in some parts of the town after a heavy rain the houses are flooded, the water being simply diluted sewerage. Mr. Carruthers is, therefore, of opinion that to drain the city and suburbs effectually provision must bo made for the removal by underground drains of the house slops, rainfall, and artesian overflow, and he submits plans of the scheme, These plans will, we suppose, be submitted to Mr. Clark, who will be expocted to express an opinion as to whether thoy are likely to effectually carry out what is aimed at —the removal of house slops, rainfall, and artesian overflov. If ho is satisfied that they will do *>, there the matter will rest. If he is not, he will, wo suppose, suggest such modifications' as will, in his opinion, provide a satisfactory drainage schouie for the city and suburbs.