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Resumptions.
This scheme necessitated the removal of all villages, and the resumption of all cultivated land, in the Shing Mun Valley above the site of the Gorge Dam. The villagers were compensated partly in cash and partly by the provision of new ac- commodation at other places in the New Territories.
Access Road Tsun Wan to Pineapple Pass.
This road was constructed to provide access to the Shing Mun Valley, both for the construction and subsequent maintenance of the new works.
Work was commenced in 1923 and was completed early in 1926. The road commences near the 8th mile-stone on the Castle Peak Road and terminates at Pine- apple Pass. It has a length of 1.92 miles, a minimum width of 16 feet, a gradient of 1 in 16 for the first mile and slightly flatter grades thereafter, a short length near its upper terminus being 1 in 17.
The work generally consisted of cutting away the hillside at spurs and tipping to form the roadway on embankment at re-entrants, and was partly in soft and partly in rock excavation.
A few retaining walls were constructed where required, and a reinforced con- crete beam and slab type bridge of 20 foot span was provided to carry the roadway over the stream near Wa Li Hop Village.
The roadway was surfaced with tar macadam for its whole length, a founda- tion of lime and cement concrete being provided where necessary.
The removal of 56,000 cubic yards of soft and 6,440 cubic yards of rock excavation was involved in the construction of the road.
Intake Dam and Temporary Conduit.
These works, which were commenced in 1925 and completed in 1926, are of a temporary nature only, their main function being to intercept the water of the Shing Mun River at the required elevation and pass it into the North Conduit until the No. 2 or Gorge Dam, which is to be provided in a subsequent section of this scheme, is constructed. They will then be no longer required and will, in fact, be submerged.
The Intake Dam, which is situated across the main stream, intercepts water and diverts it into the temporary conduit, whence the water flows into the North Con- duit.
The dam, which has been founded on solid rock, contains 594 cubic yards of cement concrete with displacers. It has a maximum length of 115′ 6′′ at an elevation of 525.00 A.O.D., and a maximum height of 34′ above foundations and 26′ above stream bed. It is provided with an overflow 50′ wide x 10' deep, the cill of which is at an elevation of 515.00 A.O.D. The draw off to the temporary conduit is controlled by means of a 24" penstock, and a gauge basin with a V. notch has been constructed to measure the amount of water supplied to the Conduit.
An automatic recorder, to measure the flood discharge of the river, has been installed and housed at a site adjoining the gauge basin.
The conduit has been constructed of lime and cement concrete lined with cement mortar. It has a gradient of 1 in 272, a length of 6,030′ and a capacity of 10 million gallons per day.
The line of the conduit generally conforms to the contour of the ground, but short lengths of reinforced cement concrete box type aqueducts, supported on piers, were utilized to carry the water across small depressions. Overflows have been constructed at all stream crossings to divert to the main stream any water in excess of the capacity of the conduit.