Testing the robustness of optimal operating plans under various future hydro-climatic scenarios
- Godoy, Walter, Barton, Andrew, Wilson, K., Perera, B.
- Authors: Godoy, Walter , Barton, Andrew , Wilson, K. , Perera, B.
- Date: 2018
- Type: Text , Conference paper
- Relation: 2018 Hydrology and Water Resources Symposium: Water and Communities, HWRS 2018 p. 267-283
- Full Text:
- Reviewed:
- Description: A key challenge for water resources planning processes around the world is to develop operating plans that are optimal under a range of hydro-climatic conditions. The consequences of such long term planning decisions can vary in terms of the social, economic, and environmental impacts. Given these potential impacts, it is important that operating plans are tested under a range of hydro-climatic conditions to ensure that they are sufficiently robust to withstand future changes in climate. The aim of this study is to present a procedure for testing the robustness of optimal operating plans for complex water resources systems using a combined multi-objective optimisation and sustainability assessment approach. The approach embeds an optimisation-simulation (O-S) model which is applied to an 18-objective function multi-objective optimisation problem of the Wimmera-Mallee Water Supply System (WMWSS). The WMWSS is a multi-reservoir system located in Western Victoria (Australia) which is operated to meet a range of competing interests for water using complex operating rules. The O-S model is applied to the WMWSS to search for optimal operating plans over a 100-year period into the future assuming two plausible greenhouse gas (GHG) emission levels. The two GHG emission scenarios represent lower and higher ends of the estimated range of projected GHG emissions, providing a wide range of future hydro-climatic conditions. A robustness test is used to evaluate the validity of the most sustainable optimal operating plans under the two GHG emmission scenarios and also those found previously under a historic hydro-climatic sequence. The test results show that the status quo or base case operating plan is optimal but is neither the highest nor the lowest in terms of the level of sustainability that could be achieved in the WMWSS, under historic and the higher GHG emission scenario. Moreover, the results show that the most sustainable optimal operating plans found under the three hydro-climatic scenarios are sufficiently robust to withstand the full range of hydro-climatic conditions considered whereas the base case operating plan is not as robust. The risks involved in the implementation of operating plans which exhibit large deviations from the base case operating plan are discussed. These risks highlight the importance of problem formulation and sensitivity analysis of the optimal operating plans in order to find real world solutions to real world problems. © CURRAN-CONFERENCE. All rights reserved.
- Authors: Godoy, Walter , Barton, Andrew , Wilson, K. , Perera, B.
- Date: 2018
- Type: Text , Conference paper
- Relation: 2018 Hydrology and Water Resources Symposium: Water and Communities, HWRS 2018 p. 267-283
- Full Text:
- Reviewed:
- Description: A key challenge for water resources planning processes around the world is to develop operating plans that are optimal under a range of hydro-climatic conditions. The consequences of such long term planning decisions can vary in terms of the social, economic, and environmental impacts. Given these potential impacts, it is important that operating plans are tested under a range of hydro-climatic conditions to ensure that they are sufficiently robust to withstand future changes in climate. The aim of this study is to present a procedure for testing the robustness of optimal operating plans for complex water resources systems using a combined multi-objective optimisation and sustainability assessment approach. The approach embeds an optimisation-simulation (O-S) model which is applied to an 18-objective function multi-objective optimisation problem of the Wimmera-Mallee Water Supply System (WMWSS). The WMWSS is a multi-reservoir system located in Western Victoria (Australia) which is operated to meet a range of competing interests for water using complex operating rules. The O-S model is applied to the WMWSS to search for optimal operating plans over a 100-year period into the future assuming two plausible greenhouse gas (GHG) emission levels. The two GHG emission scenarios represent lower and higher ends of the estimated range of projected GHG emissions, providing a wide range of future hydro-climatic conditions. A robustness test is used to evaluate the validity of the most sustainable optimal operating plans under the two GHG emmission scenarios and also those found previously under a historic hydro-climatic sequence. The test results show that the status quo or base case operating plan is optimal but is neither the highest nor the lowest in terms of the level of sustainability that could be achieved in the WMWSS, under historic and the higher GHG emission scenario. Moreover, the results show that the most sustainable optimal operating plans found under the three hydro-climatic scenarios are sufficiently robust to withstand the full range of hydro-climatic conditions considered whereas the base case operating plan is not as robust. The risks involved in the implementation of operating plans which exhibit large deviations from the base case operating plan are discussed. These risks highlight the importance of problem formulation and sensitivity analysis of the optimal operating plans in order to find real world solutions to real world problems. © CURRAN-CONFERENCE. All rights reserved.
Losing stormwater: 60 years of urbanisation and reduced downstream flow
- Ebbs, David, Dahlhaus, Peter, Barton, Andrew, Kandra, Harpreet
- Authors: Ebbs, David , Dahlhaus, Peter , Barton, Andrew , Kandra, Harpreet
- Date: 2018
- Type: Text , Conference paper
- Relation: 10th International Conference on Water Sensitive Urban Design: Creating water sensitive communities (WSUD 2018 & Hydropolis 2018), 12-15 February 2018, Perth, Western Australia p. 142-151
- Full Text:
- Reviewed:
- Description: The potential for stormwater to supplement traditional water supplies from upstream catchments or groundwater is high, with claims that the quantity of additional runoff from impervious surfaces in a modern city in a temperate climate is greater than the total potable water demand. To ensure the success of Integrated Urban Water Management, it must consider the broad context of catchment management and the cumulative effect of all factors including river health. Ballarat, an inland city of approximately 100,000 people in south-eastern Australia, has many attributes necessary to potentially exploit stormwater. Given the doubling of population, tripling of residences and 90% increase in average residence size over the past 60 years, over which time flow data is available for the downstream waterway, it might be expected that the flow in the river downstream of the city within the catchment would reflect additional stormwater runoff. However, no increase in flow was detected between 1957 and 1996 while flow over the past 20 years has reduced by 60%. A water balance shows this decrease was not due to extractions as the stream has been a consistent net receiver of water from other catchments. Modelling data from the Australian Water Resources Assessment indicates that the reduction in streamflow is double what might be expected due to climatic variations. Between 1957 and 1996 there was no significant difference between modelled runoff and actual flow, however from 1997 onwards there is a significant divergence. While lower runoff may be expected during the period of drought, the rainfall-runoff relationship does not return to previous levels during latter years of rainfall. The effect is greater during higher flow months, which has significance when identifying potential additional water resources. Base flow has been reduced to the point where dry weather flow is reliant on waste water treatment plant and mine discharge. This study indicates that while impervious surfaces generate higher runoff which can cause environmental damage, making stormwater an attractive water source, consideration must be given to the impacts on the whole catchment when assessing alternative supply options.
- Authors: Ebbs, David , Dahlhaus, Peter , Barton, Andrew , Kandra, Harpreet
- Date: 2018
- Type: Text , Conference paper
- Relation: 10th International Conference on Water Sensitive Urban Design: Creating water sensitive communities (WSUD 2018 & Hydropolis 2018), 12-15 February 2018, Perth, Western Australia p. 142-151
- Full Text:
- Reviewed:
- Description: The potential for stormwater to supplement traditional water supplies from upstream catchments or groundwater is high, with claims that the quantity of additional runoff from impervious surfaces in a modern city in a temperate climate is greater than the total potable water demand. To ensure the success of Integrated Urban Water Management, it must consider the broad context of catchment management and the cumulative effect of all factors including river health. Ballarat, an inland city of approximately 100,000 people in south-eastern Australia, has many attributes necessary to potentially exploit stormwater. Given the doubling of population, tripling of residences and 90% increase in average residence size over the past 60 years, over which time flow data is available for the downstream waterway, it might be expected that the flow in the river downstream of the city within the catchment would reflect additional stormwater runoff. However, no increase in flow was detected between 1957 and 1996 while flow over the past 20 years has reduced by 60%. A water balance shows this decrease was not due to extractions as the stream has been a consistent net receiver of water from other catchments. Modelling data from the Australian Water Resources Assessment indicates that the reduction in streamflow is double what might be expected due to climatic variations. Between 1957 and 1996 there was no significant difference between modelled runoff and actual flow, however from 1997 onwards there is a significant divergence. While lower runoff may be expected during the period of drought, the rainfall-runoff relationship does not return to previous levels during latter years of rainfall. The effect is greater during higher flow months, which has significance when identifying potential additional water resources. Base flow has been reduced to the point where dry weather flow is reliant on waste water treatment plant and mine discharge. This study indicates that while impervious surfaces generate higher runoff which can cause environmental damage, making stormwater an attractive water source, consideration must be given to the impacts on the whole catchment when assessing alternative supply options.
Regression modelling for prediction of clogging in non-vegetated stormwater filters
- Meade, Ben, Khorshidi, Hadi, Kandra, Harpreet, Barton, Andrew
- Authors: Meade, Ben , Khorshidi, Hadi , Kandra, Harpreet , Barton, Andrew
- Date: 2018
- Type: Text , Conference paper
- Relation: 10th International Conference on Water Sensitive Urban Design: Creating water sensitive communities (WSUD 2018 & Hydropolis 2018), 12-15 February 2018, Perth, Western Australia p. 8
- Full Text:
- Reviewed:
- Authors: Meade, Ben , Khorshidi, Hadi , Kandra, Harpreet , Barton, Andrew
- Date: 2018
- Type: Text , Conference paper
- Relation: 10th International Conference on Water Sensitive Urban Design: Creating water sensitive communities (WSUD 2018 & Hydropolis 2018), 12-15 February 2018, Perth, Western Australia p. 8
- Full Text:
- Reviewed:
Exploring a flow regime and its historical changes downstream of an urbanised catchment
- Ebbs, David, Dahlhaus, Peter, Barton, Andrew, Kandra, Harpreet
- Authors: Ebbs, David , Dahlhaus, Peter , Barton, Andrew , Kandra, Harpreet
- Date: 2018
- Type: Text , Conference paper
- Relation: 10th International Conference on Water Sensitive Urban Design: Creating water sensitive communities (WSUD 2018 & Hydropolis 2018), Perth, Western Australia p. 131-141
- Full Text:
- Reviewed:
- Description: The rapid growth of Ballarat's urban area, an inland city of approximately 100,000 people in south-eastern Australia, suggests that it is suitable for stormwater capture and reuse. With a threefold increase in the number of dwellings in recent decades, along with a 90% increase in their average size, it should follow that there is evidence of more flow being generated from the urban areas. However, while additional runoff from the growth of impervious areas may be occurring, the overall flow in the receiving river has dramatically reduced with a 60% decrease in the rainfall-runoff relationship since 1997. This reduction in river flow seems disproportionate to any association with the Millennium Drought which occurred during 1997 to 2009. The evidence of river flow has been complicated by other changes in the catchment. A change in the rainfall-runoff relationship has been identified in other similar catchments, and may lead to significant impacts on water resource management over the long term. To better understand the impacts on river flow downstream of an urbanised catchment, the flow has been partitioned into various components over time using the daily stream flow data available from 1957. Base flow, calculated as the stream flow after periods of four or more days without rain, has decreased. Transfers, predominantly from other catchments for use as potable supply and entering the river via the waste water treatment plant, have remained steady, but now make up the vast majority of dry weather flow. While climatic variations have impacted the river significantly the actual streamflow reduction has been twice that predicted by data from the Australian Water Resources Assessment. A significant increase in the number of small farm dams due to the expansion of peri-urban living around Ballarat explains a further portion of the flow reduction. This paper highlights multiple factors which influence river flow and demonstrates how increases in urbanised area do not necessarily create additional river flow at larger aggregate scales. The investigation therefore provides a cautionary tale around assumptions of stormwater harvesting and any perceived benefit to river flow, and provides insights into the importance of collecting water information of the correct type and scale to help inform future integrated urban water management efforts.
- Authors: Ebbs, David , Dahlhaus, Peter , Barton, Andrew , Kandra, Harpreet
- Date: 2018
- Type: Text , Conference paper
- Relation: 10th International Conference on Water Sensitive Urban Design: Creating water sensitive communities (WSUD 2018 & Hydropolis 2018), Perth, Western Australia p. 131-141
- Full Text:
- Reviewed:
- Description: The rapid growth of Ballarat's urban area, an inland city of approximately 100,000 people in south-eastern Australia, suggests that it is suitable for stormwater capture and reuse. With a threefold increase in the number of dwellings in recent decades, along with a 90% increase in their average size, it should follow that there is evidence of more flow being generated from the urban areas. However, while additional runoff from the growth of impervious areas may be occurring, the overall flow in the receiving river has dramatically reduced with a 60% decrease in the rainfall-runoff relationship since 1997. This reduction in river flow seems disproportionate to any association with the Millennium Drought which occurred during 1997 to 2009. The evidence of river flow has been complicated by other changes in the catchment. A change in the rainfall-runoff relationship has been identified in other similar catchments, and may lead to significant impacts on water resource management over the long term. To better understand the impacts on river flow downstream of an urbanised catchment, the flow has been partitioned into various components over time using the daily stream flow data available from 1957. Base flow, calculated as the stream flow after periods of four or more days without rain, has decreased. Transfers, predominantly from other catchments for use as potable supply and entering the river via the waste water treatment plant, have remained steady, but now make up the vast majority of dry weather flow. While climatic variations have impacted the river significantly the actual streamflow reduction has been twice that predicted by data from the Australian Water Resources Assessment. A significant increase in the number of small farm dams due to the expansion of peri-urban living around Ballarat explains a further portion of the flow reduction. This paper highlights multiple factors which influence river flow and demonstrates how increases in urbanised area do not necessarily create additional river flow at larger aggregate scales. The investigation therefore provides a cautionary tale around assumptions of stormwater harvesting and any perceived benefit to river flow, and provides insights into the importance of collecting water information of the correct type and scale to help inform future integrated urban water management efforts.
- «
- ‹
- 1
- ›
- »