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torrents have in numerous instances been violently diverted to avoid interference with public or private property, and in some cases instead of following the line of the street the culvert passes by an indirect route under houses and occupied areas. Recent experience has afforded convincing proof that the natural order of things cannot thus be departed from without the risk of serious damage from flood. Unfortunately some of the mistakes of the past are not susceptible of an easy remedy.
Other damage within the City.
27. Besides the serious damage in the Albany and Glenealy Nullahs, the Tsing Kai Lane culvert in Wanchai was blocked and the neighbourhood flooded. A considerable landslip from the cliff on which the Naval Hospital stands completely blocked the road to Bowrington and the Cemeteries, and another slip on the north side of the same hill destroyed the back premises of some Chinese houses. On the south side of Queen's Road East the back premises of several Chinese houses were destroyed by landslips from the steep hill side which rises immediately at the back. The approaches to the Bowrington Bridge at L. on plan were carried away.
28. In the western districts of the City considerable damage, though not of a serious nature, was done on the lines of the Po Yan Street, Richmond Nullah and Shek Tong Tsui drains. At Kennedy- town the nullah which discharges into a culvert immediately above the Cattle Market overflowed, and the water swept through the market destroying the boundary wall. A number of minor casual- ties from landslips and flooding occurred but none calling for special notice.
Tytam Water-works (Reservoir and Aqueduct.)
29. The nature of the accident to the service tank in the Albany Nullah has already been de- scribed. Some 21,000 cubic yards of debris were deposited in the tank itself during the storm. The tank averages 230 feet in length and is 200 feet wide, and 30 feet deep. It has therefore a gross capacity of about 46,000 cubic yards. This solid deposit tended to reduce the presure on the sides. Immediate steps were taken to further relieve the pressure by lowering the water level in the tank. It is satisfactory to be able to record, after careful examination, that no settlement whatever can be detected in the concrete structure, nor was there any leakage from the tank.
30. Along the line of the aqueduct which is carried under the surface of the Bowen Road, several landslips took place between the service tank and the mouth of the tunnel, a distance of about three miles. Of these, three were of formidable dimensions. They occurred on the steep hill sides above the level of the aqueduct where it overhangs the Happy Valley (at M. N. O. on plan.) The debris swept across the road and aqueduct carrying away the roadway, and the superstructure of the aqueduct, for a length of about 120 yards. Fortunately the foundations remained intact, and consequently the repairs of the aqueduct present no great difficulty, either as regards time or cost, and are in fact now nearly completed.
31. Mr. COOPER estimates that during the storm at least 30,000 cubic yards of earth were carried by these landslips across the line of the aqueduct. This included besides earth, a large proportion of huge granite boulders, dislodged from the mountain sides, some of them many tous in weight. After crossing the aqueduct the course of the principal landslips followed ravines which traverse the Public Cemetery in the Happy Valley. The bridges and part of the boundary wall were destroyed, the bed of the nullah was choked, and about 5,000 cubic yards of sand were carried through the Cemetery and deposited on the Race Course below, (at P. on plan) but fortunately not a single grave was in any way injured or disturbed.
32. The great Reservoir at Tytam, and the works connected therewith suffered no serious injury. The toe of the slope of the overflow weir, and some of the earth slopes below the concrete dam were washed away.
It is satisfactory to be able to record that the manner in which the Tytam Water- works generally (ie. the great reservoir, the aqueduct, and the service tank and filter beds), have stood the severe test to which they have been subjected speaks well for the quality of the material and work- manship, and for the care bestowed on their construction.
33. It will thus be seen that of the three grave cases of damage resulting from the storm, in two instances viz.: (1) the Albany or Military Nullah (including the Tytam service tank) and (2) the Glenealy Nullah and culvert, the cause of the accidents may be traced, in part at least, to the opera- tions of man, while on the other band the great landslips along the line of the Tytam aqueduct above the Happy Valley, were entirely due to natural causes.
Damage to roads and other works outside the City and at Kowloon.
34. As already stated there was hardly a road or street in the Colony that did not suffer more or less. Landslips occurred in numerous cases, and many were on a considerable scale. Some small bridges were also either damaged or destroyed. For full details respecting these injuries I beg to refer you to Mr. COOPER's report dated 26th ultimo (Appendix D.)*
* Not printed.