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• 1. [Article] The Influence of Floodplain Restoration on Flow and Sediment Dynamics in an Urban River

  A study of floodplain sedimentation on a recently restored floodplain is presented. This study uses a two-dimensional hydro-morphodynamic model for predicting flow and suspended-sediment dynamics in the ...

  Citation × Citation Citation Abstract Copy Title: The Influence of Floodplain Restoration on Flow and Sediment Dynamics in an Urban River Author: Ahilan, Sangaralingam, Guan, Mingfu, Sleigh, Andrew, Wright, Nigel G., Chang, Heejun Year: 2016 A study of floodplain sedimentation on a recently restored floodplain is presented. This study uses a two-dimensional hydro-morphodynamic model for predicting flow and suspended-sediment dynamics in the downstream of Johnson Creek, the East Lents reach, where the bank of the river has been reconfigured to reconnect to a restored floodplain on a 0.26 km2 (26-ha) site. The simulation scenarios include 10-, 50-, 100- and 500-year event-based deposition modelling of flood events and long-term modelling using the 64 historical flood events between 1941 and 2014. Simulation results showed that the restored floodplain significantly attenuates the upstream flood peak by up to 25% at the downstream. Results also indicated that approximately 20%–30% of sediment from the upstream is deposited on the East Lents floodplain. Furthermore, deposited sediment over the simulated period (1941–2014) is approximately 0.1% of the basin's flood storage capacity; however, the reduction in the storage does not offset the overall flood resilience impact of the flood basin. The sediment conservation at the East Lents flood basin as predicted by the model reduces the annual sediment loading of the Johnson Creek by 1% at the confluence with Willamette River, providing both improved water quality and flood resilience further downstream. Title: The Influence of Floodplain Restoration on Flow and Sediment Dynamics in an Urban River Author: Ahilan, Sangaralingam, Guan, Mingfu, Sleigh, Andrew, Wright, Nigel G., Chang, Heejun Year: 2016 A study of floodplain sedimentation on a recently restored floodplain is presented. This study uses a two-dimensional hydro-morphodynamic model for predicting flow and suspended-sediment dynamics in the downstream of Johnson Creek, the East Lents reach, where the bank of the river has been reconfigured to reconnect to a restored floodplain on a 0.26 km2 (26-ha) site. The simulation scenarios include 10-, 50-, 100- and 500-year event-based deposition modelling of flood events and long-term modelling using the 64 historical flood events between 1941 and 2014. Simulation results showed that the restored floodplain significantly attenuates the upstream flood peak by up to 25% at the downstream. Results also indicated that approximately 20%–30% of sediment from the upstream is deposited on the East Lents floodplain. Furthermore, deposited sediment over the simulated period (1941–2014) is approximately 0.1% of the basin's flood storage capacity; however, the reduction in the storage does not offset the overall flood resilience impact of the flood basin. The sediment conservation at the East Lents flood basin as predicted by the model reduces the annual sediment loading of the Johnson Creek by 1% at the confluence with Willamette River, providing both improved water quality and flood resilience further downstream. Close

• 2. [Article] Modeling of Historic Columbia River Flood Impacts Based on Delft 3D Simulations

  Natural and anthropogenic processes over the past 150 years have altered the bathymetry of the Lower Columbia River (LCR) and have changed the long wave propagation of tides and floods. Possible causes ...

  Citation × Citation Citation Abstract Copy Title: Modeling of Historic Columbia River Flood Impacts Based on Delft 3D Simulations Author: Helaire, Lumas Terence Year: 2016 Natural and anthropogenic processes over the past 150 years have altered the bathymetry of the Lower Columbia River (LCR) and have changed the long wave propagation of tides and floods. Possible causes for the increase in tidal amplitudes (+7% in tidal range in Astoria) are decreases in river discharge, lengthening of the river channel due to the construction of jetties at the mouth, dredging and deepening of the shipping channel, and reduction of the tidal prism due to the filling and diking of tidal wetlands. In this study, changes in the characteristics of long waves are elucidated by developing two hydrodynamic models of the LCR which reflect historical and modern bathymetric conditions and forcing. The historic model simulates late 19th century conditions and is extensively validated using recently recovered tide records along the LCR (e.g., Astoria, 1853-1876) and river stage measurements (e.g., Portland, 1876-1964). Results suggest that water levels in Portland at low river discharge are up to 0.5-1.0m lower than in the past. However, historical water levels during a flood scenario based on the 1880 spring freshet are similar to modern water levels. Since tidal range in the modern scenario is persistently higher at all locations, the flood risk in many locations along the LCR has increased for the same boundary conditions. The results are explained by considering the governing equations of momentum and mass-conservation. At low river flow, greater depth leads to reduced frictional effects, producing amplified tidal range and tidal velocities but a decreased river slope (and lower Portland water levels). At high flow, the modern flood is confined by dikes and the loss of wetlands, which counteracts the effect of decreased friction. Nonetheless, the high friction of the historical wooded floodplain also confined the historical flood path. Hence, historical and modern flood heights are surprisingly similar, though scaling analysis suggests that the historical flood wave was more diffusive. Title: Modeling of Historic Columbia River Flood Impacts Based on Delft 3D Simulations Author: Helaire, Lumas Terence Year: 2016 Natural and anthropogenic processes over the past 150 years have altered the bathymetry of the Lower Columbia River (LCR) and have changed the long wave propagation of tides and floods. Possible causes for the increase in tidal amplitudes (+7% in tidal range in Astoria) are decreases in river discharge, lengthening of the river channel due to the construction of jetties at the mouth, dredging and deepening of the shipping channel, and reduction of the tidal prism due to the filling and diking of tidal wetlands. In this study, changes in the characteristics of long waves are elucidated by developing two hydrodynamic models of the LCR which reflect historical and modern bathymetric conditions and forcing. The historic model simulates late 19th century conditions and is extensively validated using recently recovered tide records along the LCR (e.g., Astoria, 1853-1876) and river stage measurements (e.g., Portland, 1876-1964). Results suggest that water levels in Portland at low river discharge are up to 0.5-1.0m lower than in the past. However, historical water levels during a flood scenario based on the 1880 spring freshet are similar to modern water levels. Since tidal range in the modern scenario is persistently higher at all locations, the flood risk in many locations along the LCR has increased for the same boundary conditions. The results are explained by considering the governing equations of momentum and mass-conservation. At low river flow, greater depth leads to reduced frictional effects, producing amplified tidal range and tidal velocities but a decreased river slope (and lower Portland water levels). At high flow, the modern flood is confined by dikes and the loss of wetlands, which counteracts the effect of decreased friction. Nonetheless, the high friction of the historical wooded floodplain also confined the historical flood path. Hence, historical and modern flood heights are surprisingly similar, though scaling analysis suggests that the historical flood wave was more diffusive. Close

• 3. [Image] Flood Spreading in Arid Areas: Hydraulic and Agronomic Aspects

  	Citation × Citation Citation Abstract Copy Title: Flood Spreading in Arid Areas: Hydraulic and Agronomic Aspects Year: 1977 Title: Flood Spreading in Arid Areas: Hydraulic and Agronomic Aspects Year: 1977 Close

• 4. [Image] Stream Flow Gauging

  	Citation × Citation Citation Abstract Copy Title: Stream Flow Gauging Year: 1997 Title: Stream Flow Gauging Year: 1997 Close

• 5. [Image] Expected flooding of the Nile will be in the middle range next year

  	Citation × Citation Citation Abstract Copy Title: Expected flooding of the Nile will be in the middle range next year Year: 1986 Title: Expected flooding of the Nile will be in the middle range next year Year: 1986 Close

• 6. [Image] Israel floods drained swamp to bring in tourists

  	Citation × Citation Citation Abstract Copy Title: Israel floods drained swamp to bring in tourists Author: Watzman, Haim Year: 1993 Title: Israel floods drained swamp to bring in tourists Author: Watzman, Haim Year: 1993 Close

• 7. [Image] International Water Resources Law

  	Citation × Citation Citation Abstract Copy Title: International Water Resources Law Year: 1972 Title: International Water Resources Law Year: 1972 Close

• 8. [Image] Water Resources Law

  	Citation × Citation Citation Abstract Copy Title: Water Resources Law Year: 1970 Title: Water Resources Law Year: 1970 Close

• 9. [Image] Primer on Water

  	Citation × Citation Citation Abstract Copy Title: Primer on Water Year: 1960 Title: Primer on Water Year: 1960 Close

• 10. [Image] Ground Water

  	Citation × Citation Citation Abstract Copy Title: Ground Water Year: 1992 Title: Ground Water Year: 1992 Close