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An integrated model system is based on downscaling from climate models, to wave climate and continental shelf models for tides and surge, to coastal models for waves and water levels, to beach levels and overtopping of sea defences and inundation. Present operational practice in the UK is described. The model system is applied to the prediction of flooding at Walcott on 9 November 2007. Inundation levels are predicted in reasonable agreement with those at certain residential properties in Walcott as reported by the occupants. The effect of time-varying and time-averaged overtopping discharge is considered. Sensitivity of overtopping and inundation to uncertainties in nearshore wave height and water level is analysed, with the greatest sensitivity being to water level. Extreme joint probability analysis is undertaken, showing the event to be close to a 1 in 100-year event. Finally, the effects of different rates of sea level rise and a climate change scenario are investigated for 2100; the simulations indicate that the return period of the equivalent 2007 event could reduce to less than 2 years with a 0.5m sea level rise.

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The Lower Ausable River discharges into Lake Huron near the hamlet of Port Franks, south of Grand Bend, Ontario. Port Franks has a long history of icerelated flooding problems. The Ausable Bayfield Conservation Authority (ABCA) has conducted several hydraulic studies of the Lower Ausable River in the past to identify critical ice jam formation areas and recommend measures to minimize flooding hazards to properties along the river.The ABCA has recently undertaken an update of these studies, covering a 9.2 km (5.7 mi) reach that was originally channelized for drainage purposes over 130 years ago. The objective of the study was to identify river sections most susceptible to the formation of ice jams through hydraulic modeling, and to recommend a set of mitigative measures that address the resultant flooding. Key project challenges have included the economy of data collection methodologies (e.g., the use of digital bathymetric soundings and land terrain models, augmented with new GPS survey) as well as addressing new environmental permitting requirements.This chapter presents a summary of the ice management study procedures and findings, including a summary of the theory of ice jam formation, hydraulic modeling methodologies, the identification and prioritization of susceptible ice jam locations, and an overview of mitigative measures (that is, structural and operational controls) to minimize ice jam potential. A key highlight of this

The paper describes a project in which colour and infra‐red video images were used as the basis for assessing the percentage impermeability of subcatchments for a WALLRUS model. The imagery was obtained from helicopter‐mounted video cameras. Computer processes were developed to convert raw data, which were in analogue format, into a format which could be manipulated and displayed by the computer. The computer was able to assess the total permeable and impermeable areas in each subcatchment. These data were used in the WALLRUS model and compared with the results obtained using manually derived data and results from the flow verification survey.