Leakage is a common problem for pressurized water conduit. Currently available leakage assessment methods require reasonable penetration of accurate metering and simultaneous flow measurements at critical locations continuously for a period. To address inadequacy of accurate flow meters, water levels were measured and converted to flows for assessment in this study. Meanwhile, to enable "simultaneous" measurements at the constraints of metering, manpower and transport, a steady state flow

more »

... ion is maintained throughout the assessment period. This is done by keeping the driving force of the water conveyance tunnel being studied, which is the generated power of the downstream hydropower plant constant. Then, water balance was applied to the single set of average measurements taken at all critical locations for leakage assessment. This method has proven to be useful in assessing leakage condition for the system with metering, manpower and transport constraints. However, the assessment results may be affected by measurement performance.