Hydrologic Analysis And Emergency Application Of Barrier Lake Breaking

After the severe earthquake of"5.12"Wenchuan of Sichuan province in 2008, hundreds of barrier dams were formed in earthquake zone, giving rise to a multitude of hidden hazards. Especially, the Tangjiashan Barrier Lake poses the largest threat because it has a high dam, huge capacity, and unstable geological condition. If it break, the flood would threaten more than one million people in downstream Mianyang city. The protential loss could be even bigger than the earthquake itself. In order to safely, scientifically and quickly remove the hazards of Tangjaishan Barrier Lake, the government has to implement a series of steps about structural and non-structural measures within short time. For this, emergency hydrologic analysis is indispensable. At present, relevant research is not systematic and thoroughgoing. It is necessary to set up emergency hydrologic analysis system to face emergency management and to treat emergency water events in hydrologic industry, and to study the techniques and methods.The paper attempts to establish the working steps and frame model of emergency hydrologic analysis. It includes three major phrases: sketchy investing phrase, local measuring and treatment implementing phrase and treatment analysis phrase. And more, it includes six steps including sketchy invesgating, data collecting, sketchy analyzing, treating monitoring, and accurate analysis and continuously scrolls analyzing. In every step it faces different object and task. Because of lack of hydrologic gauges and history data, we provide the principle of model using in order to satisfy the fast and accurate request.It is successful to applying in the emergency treating on Tangjiashan Barrier Lake. Under the principle of emergency hydrologic gauge net building, we investigate local sites of every station and to argue about it. We finish the scheme about emergency hydrologic monitoring and to attain the first-hand rainfall and hydrologic data. It made the base for barrier lake treatment. At same time, we made the early-warning signals about hydrologic elements. It used to avoid danger for the downstream people while the flood went down. The paper uses systemic analysis method and multi-way merging technique to optimize and select the hydrologic forecasting models, and to make the principle of adaptable key technique.The successful application of Tangjiashan Barrier Lake treatment gathered a lot of experience of emergency hydrologic analysis and tested the routines of technique. The procedure is basic for treating semergency water events in future too. And it would help to establish the hydrologic system about emergency management at higher level.