Mangahao release postponed February 11th, 2020 2010-04-07T10:52:49+12:00 Mangahao Joint Venture has advised that the Mangahao release this Saturday will be postponed. A test operation on the the No. 2 dam bypass gate was carried out yesterday after problems with the gate forced the cancellation of last October’s release. Unfortunately, the gate failed to open yesterday and remains jammed closed. The result came as a surprise as the gate opening was successfully tested earlier this year. If the gate can be repaired, a replacement date will be advertised for a Saturday in May. Access