656551-1890-Report-on-Separate-System-of-Main-Drainage — Page 17

THE HONGKONG GOVERNMENT GAZETTE, 27TH SEPTEMBER, 1890.

His report states as follows:---

"I hope to show that the existing sewers of Victoria may be improved so as to fit them for the conveyance "of sewage, besides serving to carry the storm water to the harbour, as they do at present, and further, that the sewage, during dry weather, may be diverted from their lower extremities, and carried to some distant outfall, “where it will be innocuous.”

This I propose to call the Combined System.

947

between Mr.

Combined

System and

Separate

The proposed scheme of drainage, as described in the report under consideration, is diametrically opposed to Difference that of Mr. CHADWICK, in that it separates the sewage from the rainfall over the entire area of the City in the Chadwick's most minute way, leaving the present drains for the conveyance of rainfall only, and laying down a complete new Mr. Cooper's

Those of Districts Nos. 1 System. system of pipe sewers for the conveyance of sewage leading to four main outfalls. and 2 being at Belcher's Point, No. 3, at Possession Point, and No. 4 at Bowrington Canal, this last outfall is recommended to be continued to North Point and there pumped.

This is strictly what is known as the Separate System.

Scheme, víz,

Systern for purely Chinese

The method of drainage, which I propose, may be generally described, as the adopting for the strictly Chinese Suggested portions of the City Mr. CHADWICK'S recommendation to use the present drains for the conveyance of sewage Combined and rainfall, but omitting the intercepting sewer he proposed allowing them to discharge direct into the harbour, districts. but having no connection with the few large main storm-water drains, which convey the flood water from the hill sides above through these portions of the city.

The remaining portions of the city, occupied chiefly by what may be described as the European population, Separate

System for I propose to deal with on the separate system, the hill side drainage and rainfall generally being served by the European

portion. present large storm-water drains mentioned above, and the sewage conducted by pipe drains to convenient outfalls, discharging into the harbour.

of systems

It will therefore be seen that I propose to adopt the Combined System for the purely Chinese districts, and Combination the Separate System for the Europeau; and I hope to be able to prove, that this combination of systems can be recommended. effectually and economically carried out, and that it is the most suitable to the widely different conditions to be dealt with in the drainage of this City.

Mr. Chadwick's Scheme.

discharge

into rain

The objections I have to this scheme, are, that in the upper districts of the City and wherever the houses objections to are scattered, it would not be wise to discharge the drainage from these houses into the large drains necessary to house drains take the Storm-water, as, during the dry season, there would not be a sufficient body of sewage in these large in European drains to keep up a constant flow.

water drains

districts.

intercepting

The intercepting sewer to the Sulphur Channel, owing to the depth of it, must be constructed in soil open to Objections to the sea, and, being for its entire length (6 miles) below low water level, would, owing to its enormous cost, sewer. together with the constant expense of pumping, be practically prohibitive, and I consider unnecessary, as, by properly constructed outfalls into deep water opposite the City, no nuisance would arise.

Mr. Chadwick

drains.

I entirely agree with Mr. CHADWICK in his recommendations to use the present drains for the conveyance Agreement with of sewage and rainfall over the thickly populated Chinese districts of the City, and with his remarks and sug- to use present gostions on Ventilation, trapping, house connections, improvement of the existing sewers and sanitation generally.

His admirable report contains an immense amount of most valuable and reliable information.

Mr. Cooper's Scheme.

The chief points of objection I have to this scheme are:--

1.--Attempting to separate rainfall from sewage over the thickly populated Chinese parts of the City.

2.-Dividing the City into the four districts proposed.

3. The disposal of the sewage by intercepting sewers at the four points proposed.

Before proceeding to discuss my objections, I think it would be well to describe more fully my proposals, as the pros and cons of the two schemes could then be taken together.

of Plate 1.

Plate 1 is a map of the City. The districts occupied by Chinese are coloured red, and these I propose to Description drain on the Combined System. The districts coloured yellow are chiefly occupied by Europeans, and these I Division of propose to drain on the Separate System.

districts,