Q 55
P.W.E. Hong Kong.
Waterworks:
127. Eastern Filter Beds Scheme. This work was referred to in paragraph 122 of last year's Report.
The scheme, which is primarily intended to supply the Eastern end of the City from Arsenal Street to North Point including the new Praya East Reclamation and also to relieve the present Bowen Road Conduit by taking its supply direct from the West end of the Tytam Tunnel, is now completed.
The scheme comprised the following works:-
(a.) An 18" C.I. Pipe line from Tytam Tunnel to the new Gauge Basin at the site of the new Filters.
(b.) A Gauge Basin for the new Filters.
(c.) 11 No. Slow Sand Filters.
(d.) A covered concrete Service Reservoir.
(e.) Access Road to site of Filter Beds.
(f.) Watchmen's Quarters at Filter Beds.
(g.) An 18″ C.I. Distribution Main from the Service Reservoir to the Monument at Happy Valley.
(h.) Overseers' Quarters.
In 1919 & 1920 the necessity for this work became so urgent that surveys were made, Indents sent to England for the necessary pipes, Valves &c, and also as a temporary measure, in anticipation of the scheme, Grit Filters were constructed alongside Bowen Road Conduit at a point about 900 yards from the West end of the Tytam Tunnel, a 12" temporary C.I. main was laid from the Grit Filters to the South end of Happy Valley and from thence to the Monument, an 18" C.I. main was laid the latter forming part of the permanent scheme. These preliminary works were constructed at a cost of $31,142.72 and this amount was included in the preliminary estimate of $575,000.00 for the whole scheme.
In reference to:-
(a.) An 18" C.I. Pipe line from Tytam Tunnel to the Gauge Basin. This work was carried out by Messrs. Kin Lee under the Annual Contract. It consisted of 1,620 lineal feet of main generally contouring the hillside below Bowen Road and plan piers across stream courses and having an 18" Penstock Vent at the Tunnel end with a 15″ Sluice Valve at the Gauge Basin.
(b.), (c.), (d.), (e.), and (f).-These items comprised Contract No. 12 of 1922 which was let to Messrs. Wing On at a Contract Price of $392,345.36.
The Filter Beds which are of the Slow Sand Type were constructed in two tiers, the upper tier at cope level of 25 A.O.D. and having 5 Beds and the Lower Tier at a cope level...