Problems began with one of the dam's primary objectives, assuring an abundant water supply. The lake behind the dam, targeted for filling by the time the dam went into operation in 1970, could be only half filled by opening day.
亞斯文水壩在一九五九年動工，落成前五年已開始發揮蓄水功能；技術人員原訂在落成那年蓄滿水以示慶祝，水壩卻不合作，落成後一年水仍蓄不滿。