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Printed in Great Britain. ; pt. I. The internal workings of a Chinese village [by Mr. Leong]--pt. II. The town administration [by Mr. Tao] ; Mode of access: Internet.

Abstract. Floods caused by levee breaching pose disastrous risks to the lower reaches and the flood flow zones of rivers. Thus, a comprehensive assessment of flow and sediment transport during floods must be performed to mitigate flood disasters. Given that the flow state becomes relatively more complex and the range of the submerged area becomes more extensive after a levee breach, this paper established a flow and sediment model by using two-dimensional shallow water equations (SWEs) to explore the breach development process and the flow and sediment transport in a curved bed after a levee breach due to overtopping. A three-element weighted essentially non-oscillatory Roe scheme was adopted for the discretization of SWEs. In addition, a non-equilibrium total-load sediment transport model was established to simulate the scour depth development process of the breach. A stable equilibrium of the breach was established based on flow shear force and soil shear strength. The lateral widening of the breach was simulated by the scouring-collapse lateral widening mode. These simulations, together with the levee breach experiment conducted in the laboratory, demonstrate the validity of the flow and sediment transport process established in this paper. The effects of water head in and out of the watercourse, the flow rate, the levee sediment grading, and other variables during levee breaching were also analyzed. The mathematical model calculation provided a number of physical quantities, such as flow rate and flow state at the breach, that are difficult to measure by using the current laboratory facilities. The results of this research provide fundamental data for developing measures that can reduce casualties and asset loss due to floods caused by levee breaching.

This study carries out an in-depth analysis of urban water policy implementation in China through a policy cycle analysis and case study of Sponge city program. The policy cycle analysis articulates discrete steps within the policy formulation and implementation process, while the case studies reflect the specific problems in water project implementation. Because of the principal-agent relation between central and local government, a "double wheel" policy cycle model is adopted to reflect the policy cycles at central level and at local level. Changde city and Zhuanghe city, two demo cities in the Sponge city program, are chosen for the analysis. The policy cycle analysis shows that the central government orders local government to implement policy without clear direction on how to attract private sector participation. The evaluation of central government did not include private sector involvement, nor the sustainability of the investments. This promotes the local government's pursuit of project construction completion objectives, without seriously considering private sector involvement and operation and maintenance (O&M) cost. The local governments do not have political motivation and experiences to attract private investments into project implementation. The case study in the two demo cities shows that local government subsidies are the main source of O&M funding currently, which is not sustainable. The water projects are not financially feasible because no sufficient revenue is generated to cover the high initial investments and O&M cost. The lack of private sector involvement makes it difficult to