DRAINAGE OFFICE
Chief Engineer, W. A. Johnson, A.M.I.Mun.E., A.R.I.C.S.
General
171. Rainfall during the year was below average and rainstorm and typhoon damage was on a small scale.
172. The rate of building development showed little diminution and drainage extensions totalled a little over 9 miles of foul sewers and storm-water drains. Approximately half of these extensions served private estate development and were carried out at the cost of the developers.
173. The general maintenance and other necessary works in Government air raid tunnels was undertaken during the year.
Sewerage
174. Owing to the shortage of rain during the winter, nullah supplies of flushing water were unusually low and gave cause for anxiety in some instances. This shortage, together with the severely restricted hours of mains water supply, resulted in insufficient flow in many of the sewers and a large number of chokes and other minor nuisances occurred. Sewer gangs cleared approximately 8,000 chokages during the year representing an increase of some 500 over the previous year.
175. Work continued throughout the year on the construction of the main intercepting sewers for the Yaumati Drainage Scheme, and the large diameter trunk mains, together with the outfall to the shore-line, were completed. Plant was ordered from England for the pumphouses and outfall screens.
176. The steady development of the Wongneichong valley during recent years has transformed it into a densely populated area and the old sewers eventually became overloaded to such
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