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| * “It is common to consider adapting stormwater systems to climate change by adding simple uplifts to rainfall intensities and then assessing whether or not the existing system can cope or not (e.g., Defra, 2010; Semadeni-Davies et al., 2008). This is the Predict-Then-Adapt method which begins by considering the changing climate system (drivers) and the consequent pressures (e.g., increased runoff), state (e.g., system performance) to predict the impacts (e.g., flooding and pollution). Responses then need to be formulated to deal with the pressures and impacts in a way that maintains expected levels of performance. This method has been classified as cause-based after its reasoning (Jones and Preston, 2011). The main problem with it is the reliance on estimated climate change scenarios that are expected to provide some precision as regards forecasts of climate change. However, despite past and current scientific advances in climate modelling, there remain large uncertainties about the direction, rate and magnitude of climate change” Gersonius et al 2012. | | * “It is common to consider adapting stormwater systems to climate change by adding simple uplifts to rainfall intensities and then assessing whether or not the existing system can cope or not (e.g., Defra, 2010; Semadeni-Davies et al., 2008). This is the Predict-Then-Adapt method which begins by considering the changing climate system (drivers) and the consequent pressures (e.g., increased runoff), state (e.g., system performance) to predict the impacts (e.g., flooding and pollution). Responses then need to be formulated to deal with the pressures and impacts in a way that maintains expected levels of performance. This method has been classified as cause-based after its reasoning (Jones and Preston, 2011). The main problem with it is the reliance on estimated climate change scenarios that are expected to provide some precision as regards forecasts of climate change. However, despite past and current scientific advances in climate modelling, there remain large uncertainties about the direction, rate and magnitude of climate change” Gersonius et al 2012. |
| *“It should be noted that although the stormwater management initiatives that are proposed to be integrated into Toronto’s street network will not contribute significantly to mitigating the impacts of extreme precipitation events, they will improve the function and resilience of existing stormwater infrastructure by reducing runoff volumes, thereby freeing up capacity within the downstream stormwater drainage system” City of Toronto 2016 (green streets technical guidelines) | | *“It should be noted that although the stormwater management initiatives that are proposed to be integrated into Toronto’s street network will not contribute significantly to mitigating the impacts of extreme precipitation events, they will improve the function and resilience of existing stormwater infrastructure by reducing runoff volumes, thereby freeing up capacity within the downstream stormwater drainage system” City of Toronto 2016 (green streets technical guidelines) |
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| ==‘No-regrets’ approach==
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| This is an approach referenced in few different studies and seems to fit well with the benefits of LID in light of climate change. Tie back to the fact that climate change projections are uncertain, especially at local scales, so why not implement LIDs – they are practices that work well for stormwater management with and without the effects of climate change.
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| *Climate change should be considered in future planning but the uncertainty in estimates makes it harder for those involved
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| *“Acknowledging that there is uncertainty as to how the climate will change and at what rate, the team developed strategies that are built upon three principles which ensure that their recommended actions make sense under any scenario: • Triage: Avoiding efforts that are unlikely to succeed and concentrating on areas where improved management can have the biggest impact; • Precautionary principle: Not waiting for certainty to act where the consequences of potential impacts are high; and • No regrets: Focusing on actions that provide benefits regardless of how the climate changes (Wisconsin Initiative on Climate Change Impacts, 2011).” Huron River Watershed Council, 2013
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| *“No-regrets actions are those that provide benefit under both current climate conditions and potential future climate conditions. No-regrets options increase resilience to the potential impacts of climate change while yielding other, more immediate economic, environmental, or social benefits (Heltberg et al, 2008). The no-regrets approach is considered “proactive adaptive management” which is based on the development of a new generation of risk-based design standards that take into account climate uncertainties. There are a wide variety of no- regrets actions that improve the adaptive capacity of the watershed to handle stormwater.” Huron River Watershed Council, 2013
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| *‘No-regrets’ strategies “Faced with uncertainty about future climate change, and given constraints on available resources, communities may choose to pursue no-regrets strategies – actions that are beneficial in addressing current stormwater management needs regardless of whether or how climate may change in the future (Means, Laugier, Daw, Kaatz, & Waage, 2010)”. -Cited in Pyke et al 2011. “The results of this study also demonstrate the effectiveness of site redevelopment, including increased density and reduced impervious cover as a no-regrets adaptation strategy for reducing pollutant loads associated with stormwater runoff.” Pyke et al 2011. “management infrastructure, a challenge that many practitioners and decision makers are just beginning to consider (Blanco, Alberti, Forsyth, et al., 2009; Blanco, Alberti, Olshansky, et al., 2009). Responding to climate change will be complicated by the scale, complexity, and inherent uncertainty of the problem, therefore it is unlikely that this challenge can be solved using any single strategy. The scenario analyses conducted in this study illustrate the potential effectiveness of one common element of LID, reducing impervious cover, in the context of climate adaptation.” Pyke et al 2011
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| *“Managing green infrastructure for climate adaptation is primarily about managing risks or uncertainties created by anthropogenic activities. The risk-based approach to climate change has three defining aspects: problem framing and role; embedded policy discourse; and planning approaches. First, problems associated with adverse weather conditions, including rainstorms, floods, heat waves and cyclones, tend to be understood in probabilistic terms. The ‘thing’ that matters is not discrete material benefits that can fulfill the needs of the public, but non-linear, irreducible uncertainties associated with changes in the climate. Functioning as a risk buffer, green infrastructure actually helps minimize the impacts of public ‘bads’ (i.e. natural perils) and, by doing this, indirectly provides public ‘goods’. There is limited precision as to where and when these impacts will eventuate and in what manner. The ‘necessity’ for green infrastructure is thus reduced to a matter of probabilities that are influenced by global climatic dynamic and humanity’s collective actions. It is driven by problems that we seek to avoid and are unable to predict with high level of precision.” Matthews et al 2015
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| ==Water as a valuable resource== | | ==Water as a valuable resource== |