Cross jurisdictional barriers to effective wastewater reuse : management of wastewater disposal, water quality impacts, and reform opportunities for Australia

摘要

Reduced wastewater disposal through reuse can provide improved environmental, economic and social outcomes. Under the Australian Constitution, states and territories have the power to make laws over water and therefore there is considerable variation in the approaches taken by various Australian jurisdictions to urban wastewater management, urban water industry governance, and the management of discharge environments including recreational water. This thesis considers whether urban water governance, environmental regulation and recreational water quality management impact decisions to either reuse urban wastewater or dispose of it to the environment, and identifies opportunities for reform.udChapter 2 reviews Australian urban wastewater management and environmental regulation and barriers to wastewater reuse. Australian water quality standards are contained in non-binding national guidelines which are applied by states in policies and licences granted under pollution control legislation. A range of barriers to wastewater recycling have been identified including an inability to account for the external impacts of water management.udChapter 3 follows with a case study of the decision process for a wastewater reuse scheme in Beaconsfield, Tasmania. Circumstances leading to recent reform of urban water management and historically poor environmental performance are described. These demonstrate how investment decisions are biased by urban wastewater governance, economic policies for pricing and profits, application of principles of competition in absence of competition, and the level of past investment.udChapter 4 considers how environmental management and other factors may impact assessment of costs and benefits of reuse. This is done by comparing the Chapter 3 case study (Beaconsfield) to wastewater reuse planning by Hunter Water (NSW) revealing that the feasibility of wastewater reuse technologies changes with the conditions in which the feasibility of reuse is framed; in Tasmania, different outcomes were observed under the same non-binding environmental guidelines and influences including 1) the comparative level of formality or transparency in the assessment processes, 2) the different drivers for wastewater reuse (environmental protection or water scarcity), and 3) the ability for environmental regulations to account for external impacts of wastewater disposal; providing new knowledge to this research area.udIn order to test an assumption within reuse feasibility assessments that effective Australian environmental regulations negate the economic impacts of discharge as a benefit from wastewater reuse, Chapter 5 examines Australian recreational water quality management, drawing on examples from the USA and more progressive Australian jurisdictions. This represents the first study of the legal efficacy of Australian recreational water management, also providing new knowledge. The chapter concludes that despite national guidelines, there remains high inter-jurisdictional variation in recreational water quality management. Recommendations for reform include: 1) management actions based on single high samples, 2) consistent communication, 3) consistent microbiological limits, 4) consistent levels of acceptable health risk for primary and secondary recreational activities, and 5) model policy mechanisms to facilitate these.udTwo further case studies support the findings of Chapter 4. Firstly, Chapter 6 considers wastewater discharges by Melbourne Water Corporation at Gunnamatta beach in Victoria, Australia, identifying that even though the discharge was apparently compliant with legislation and policy, there was environmental degradation, a divergence from the national approach for recreational water quality management to a less accurate methodology, and a water authority that stated or implied that their discharge represented no risk to human health; all of which has the potential to affect bathers’ abilities to make informed and safe recreational choices. Secondly, in Chapter 7, management of Combined Sewage Overflows (CSO) in Tasmania and the USA are compared demonstrating that the application of non-binding national and state water quality guidelines has facilitated a parlous level of infrastructure investment. A case study of proposed US laws, which would require public notice when untreated effluent is disposed from CSOs, is put forward as a model for reform.udWeaknesses in recreational water quality management and variation in the extent to which environmental regulations and monitoring programs account for impacts of wastewater disposal contradict the key assumption used when comparing economic costs and benefits of wastewater disposal and wastewater reuse. The assumption is that Australian environmental regulation is effective and therefore compliance reflects socially optimal conditions. Inadequate recreational water management is therefore a new barrier to wastewater reuse which acts alongside the barriers to wastewater reuse identified earlier in the thesis. Proposed reforms include; 1) the ability of decision makers to account for the external impacts of wastewater disposal, 2) improved communication of the externalities of disposal which impact community willingness to pay for recycled water, and 3) mechanisms for more consistent application of non-binding environmental guidelines. Addressing these will assist the incorporation of the true costs of wastewater disposal into decisions to either reuse or dispose of wastewater.