Environmental Water Allocations Research Articles

The importance of context in relation to policy transfer: a case study of environmental water allocation in Australia

AbstractLearning from the experiences of other jurisdictions has become a common strategy in the face of increasing severe environmental problems around the world. This phenomenon is very common in the water field, where surveys of institutions in other jurisdictions are widely used by practitioners to identify models that can be adopted. A precondition for success in policy transfer is careful consideration of the context within which institutions were developed. This paper explores the importance of context using the example of institutions for environmental water allocation (EWA) in the Murrumbidgee Catchment, in NSW, Australia. The case of EWA in the Murrumbidgee Catchment clearly demonstrates that, in the context of water policies, biophysical considerations must be considered alongside political, social, economic and cultural considerations when evaluating the extent to which water policies designed for one setting can be adopted elsewhere. Copyright © 2010 John Wiley & Sons, Ltd and ERP Environment.

Integrated Hydrologic-Economic-Institutional Model of Environmental Flow Strategies for Rio Yaqui Basin, Sonora, Mexico

An integrated hydrologic-economic-institutional water model was developed for the Rio Yaqui Basin, located in northwest Mexico, with the objective of assessing the impacts on agricultural economic benefits from strategies for allocating environmental flow. This paper focuses on the creation of simulation models that estimate the agricultural net benefits under different environmental flow scenarios and surface water allocation strategies. The results illustrate a trade-off between interannual variability of environmental flows and variability in agricultural benefits, corresponding to economic risk, for three allocation strategies. Results also show that environmental flow allocations affect groundwater levels through impacts on surface-ground water interactions.

18. Australia

In June, Julia Gillard replaced Kevin Rudd as prime minister of Australia. The leadership shift was attributed to, among other things, inaction on climate change. Yet Australia has still not enacted national climate mitigation legislation since the introduction of a national emissions trading scheme was deferred. Political debate around Prime Minister Gillard’s proposed price on carbon continues (discussed later in this report). As a fitting backdrop to the climate change debate, the year also brought several extreme weather events. After a decade of drought, Australia experienced its third wettest year on record, as El Niño gave way to a strong El Niña weather pattern. Despite this deluge, a lack of water remains a serious pressure on Australian ecosystems and biodiversity. Australia currently is in the process of developing the Murray Darling Basin Plan (MDB Plan) under national water legislation in order to address these serious water allocation issues (<http://thebasinplan.mdba.gov.au>). The Water Act 2007 seeks to give effect to international agreements for biodiversity protection such as the Convention on Biological Diversity (CBD). The consultation stage of the MDB Plan has highlighted the difficulties of balancing environmental and human demands for water. How the MDB Plan sits with Australia’s new Biodiversity Strategy, which was released in 2010, will be an issue to watch in the coming year. One particular concern will be how Australia is to meet its obligations under the Convention on Wetlands of International Importance, Especially as Waterfowl Habitat (Ramsar Convention) in light of competing demands and limited environmental water allocations. More positively, Australia has continued its active involvement in the international effort to halt whaling in the Southern Ocean Sanctuary, including the commencement of litigation against Japan in the International Court of Justice (ICJ).

Longevity and larval development among southern bell frogs (Litoria raniformis) in the Coleambally Irrigation Area - implications for conservation of an endangered frog

Context. With the flow of many of the world’s rivers regulated such that water can be diverted for agriculture and human consumption, basic ecological information on the current status of key biota in significant floodplain wetlands and their response following inundation is needed. The maintenance of natural habitat to ensure amphibian survival is gaining increasing recognition, given the ongoing decline of anuran populations. Information on longevity, time required to emerge from the water and to reach sexual maturity, all provide important information about the required timing, frequency and duration of environmental water allocations to ensure successful recruitment among populations of southern bell frogs (Litoria raniformis Keferstein, 1867). Aims. The aims of this research were to establish the longevity of southern bell frogs in the Coleambally Irrigation Area (CIA) in the Riverina region of New South Wales, Australia, and to evaluate the capacity for southern bell frog tadpoles to survive and successfully metamorphose following an extended overwintering period. Methods. Skeletochronology studies were carried out using toe-clips taken from adult and juvenile frogs captured in irrigation channels and rice fields over two rice-growing seasons. For the metamorphosis assay, southern bell frog tadpoles were held back in their development by low temperatures and low food allocation for 290 days, before temperatures and food allocation were increased adequately to allow metamorphosis to occur. Key results. The study indicated that skeletochronological examination of toe-bones was a useful technique for establishing the age structure of southern bell frogs in this region. The oldest animals in the population were found to be 4–5 years old, although the majority of frogs were typically 2–3 years old. Also, the metamorphosis assay indicated that successful metamorphosis was the exception rather than the rule if tadpole development was held back by low food ration and low temperatures. Conclusions. If southern bell frogs reach sexual maturity only after 2 years, and the oldest animals observed in the field are 4 or 5 years old, then there is a very narrow window of opportunity – two to three seasons – for each individual to successfully breed. Implications. The implications for environmental flow management are that habitats for key species identified for protection such as the endangered southern bell frog will need water every 1–2 years to enable each cohort to breed and maintain the wild populations. The extent of the environmental flows needs to be adequate to ensure that water persists long enough for critical biological events such as anuran metamorphosis to occur during the spring and summer months.

Adaptive management of an environmental watering event to enhance native fish spawning and recruitment

Summary1. A common goal of many environmental flow regimes is to maintain and/or enhance the river’s native fish community by increasing the occurrence of successful spawning and recruitment events. However, our understanding of the flow requirements of the early life history of fish is often limited, and hence predicting their response to specific managed flow events is difficult. To overcome this uncertainty requires the use of adaptive management principles in the design, implementation, monitoring and adjustment of environmental flow regimes.2. The Barmah‐Millewa Forest, a large river red gum forest on the Murray River floodplain, south‐east Australia, contains a wide variety of ephemeral and permanent aquatic habitats suitable for fish. Flow regulation of the Murray River has significantly altered the natural flood regime of the Forest. In an attempt to alleviate some of the effects of river regulation, the Forest’s water regime is highly managed using a variety of flow control structures and also receives targeted Environmental Water Allocations (EWA). In 2005, the largest environmental flow allocated to date in Australia was delivered at the Forest.3. This study describes the adaptive management approach employed during the delivery of the 2005 EWA, which successfully achieved multiple ecological goals including enhanced native fish spawning and recruitment. Intensive monitoring of fish spawning and recruitment provided invaluable real‐time and ongoing management input for optimising the delivery of environmental water to maximise ecological benefits at Barmah‐Millewa Forest and other similar wetlands in the Murray‐Darling Basin.4. We discuss possible scenarios for the future application of environmental water and the need for environmental flow events and regimes to be conducted as rigorous, large‐scale experiments within an adaptive management framework.

Water markets and freshwater ecosystem services: Policy reform and implementation in the Columbia and Murray-Darling Basins

Water markets have featured prominently in the reallocation of water rights to restore freshwater ecosystem health. Incentive-based water rights acquisition and transactions have emerged as a market-oriented policy approach to reallocate water resources from existing uses to enhance the provision, regulation, and sustainability of freshwater ecosystem services. This paper develops a conceptual framework to examine factors enabling and constraining successful policy reform and implementation in market-based environmental water allocation. This analysis distills and extends the findings and lessons of a September 2007 workshop in Brisbane, Australia on environmental water transactions. Two case studies were selected in water stressed basins – the Columbia (U.S.A) and Murray-Darling (Australia) Basins – where transactional approaches to environmental water allocation first emerged. The case studies draw upon practitioner perspectives and previous policy and economic analysis in two regions where shared political economic and physical conditions lend a strong analytical basis for comparison. A common set of policy and regulatory reforms has occurred in both cases – albeit in different forms and via distinct paths – to develop three enabling conditions: (1) establishment of rights to and limits on freshwater extraction and alteration; (2) recognition of the environment as a legitimate water use; and (3) authority to transfer existing water rights to an environmental purpose. However, these elements of policy reform are necessary but not sufficient for effective implementation; a second set of driving forces, barriers, and adaptations explains the ability to achieve larger scale ecological outcomes. These conditions include the physical, social and economic factors driving demand for environmental water allocation; administrative procedures, organizational development and institutional capacity to effect transfers; and adaptive mechanisms to overcome legal, cultural, economic, and environmental barriers. The case study analysis suggests that environmental water transactions can play an important role in establishing environmental water allocations, although water markets require ongoing institutional capacity and adaptive governance. The conceptual framework and empirical lessons generated through this cross-case comparison provide the basis for an expanded research agenda to evaluate the design and performance of market-oriented reforms as implementation experience accrues and new programs emerge in diverse ecological and political economic settings.

Associations between the plant communities of floodplain wetlands, water regime and wetland type

AbstractUnderstanding how floodplain wetland vegetation is influenced by water regimes can inform the management of regulated river systems by targeting appropriate environmental water allocations. In this study, we examined plant community structure in 21 floodplain wetlands adjacent to the Murray River between Hume Reservoir and Tocumwal, south‐eastern Australia. Correlations between the water regime of the previous 25 years, and wetland type were investigated. We found the structure of plant communities, as assessed by the richness and percentage cover of plants, to be related to water regime, with clear differences between the communities of wetlands with historical ‘Wet’, ‘Dry’ and ‘Intermediate’ water regimes. Plant community structure was also related to wetland type, with differences being found between the communities of floodplain depressions, flood‐runners and cut‐off meanders. Managers of riverine/floodplain ecosystems need to consider both wetland type and water regime when planning strategies for the restoration or conservation of floodplain wetland vegetation in regulated river systems. Copyright © 2009 John Wiley &amp; Sons, Ltd.

Flow and water temperature simulation for habitat restoration in the Shasta River, California

AbstractLow instream flows and high water temperatures are two factors limiting survival of native salmon in California's Shasta River. This study examines the potential to improve fish habitat conditions by better managing water quantity and quality using flow and water temperature simulation to evaluate potential restoration alternatives. This analysis provides a reasonable estimate of current and potential flows and temperatures for a representative dry year (2001) in the Shasta River, California. Results suggest restoring and protecting cool spring‐fed sources provides the most benefit for native salmon species from a broad range of restoration alternatives. Implementing a combination of restoration alternatives further improves instream habitat. Results also indicate that substituting higher quality water can sometimes benefit native species without increasing environmental water allocations. This study shows the importance of focusing on the limitations of specific river systems, rather than systematically increasing instream flow as a one size fits all restoration approach. Copyright © 2009 John Wiley &amp; Sons, Ltd.

An investigation of the hydrological requirements of River Red Gum (Eucalyptus camaldulensis) Forest, using Classification and Regression Tree modelling

AbstractRiver Red Gum (Eucalyptus camaldulensis) is widely distributed throughout many water courses and floodplains within inland Australia. In recent years, accelerated decline of River Red Gum condition has been observed in many locations, and field observations of the degradation are consistent with the reduction of flooding. However, there are few publications that quantitatively investigate the relationships between River Red Gum condition and flooding history. We applied Classification and Regression Tree (CART) to model the minimum flooding requirement of River Red Gum forest/woodland in Yanga National Park, located on the Lower Murrumbidgee Floodplain, southeast Australia, using crown conditions derived from historical aerial photographs spanning more than 40 years. The model produced has a moderate reliability with an overall accuracy of 64·1% and a Kappa index of 0·543. The model brings in important insights about the relationship between River Red Gum community type, flood frequency and flood duration. Our results demonstrated that (1) CART analysis is a simple yet powerful technique with significant potential for application in river and environmental flow management; (2) River Red Gum communities on the Lower Murrumbidgee Floodplain require periodic inundation (3–5 years) for a duration of up to 64 days to be in moderate to good conditions; (3) Although the crown conditions of different community types displayed similar degradation trends, they have distinct flooding requirements; and (4) The River Red Gum community in Yanga National Park may be managed as hydrological units given limited environmental water allocations. Copyright © 2009 John Wiley &amp; Sons, Ltd.

Effects of flooding on recruitment and dispersal of the Southern Pygmy Perch (Nannoperca australis) at a Murray River floodplain wetland

Summary With limited evidence linking Australia's Murray‐Darling Basin fish species and flooding, this study assessed annual variation in abundance and recruitment levels of a small‐bodied, threatened floodplain species, the Southern Pygmy Perch (Nannoperca australis), in floodplain habitats (creeks, lakes and wetlands) in the Barmah‐Millewa Forest, Murray River, Australia. Spring and summer sampling over a 5‐year period encompassed large hydrological variation, including 1 year of extended floodplain inundation which was largely driven by an environmental water release, and 2 years of severe regional drought. Recruitment and dispersal of Southern Pygmy Perch significantly increased during the floodplain inundation event compared with the other examined years. This study provides valuable support for an environmental water allocation benefiting a native species, and explores the link between flooding and its advantages to native fish. This suggests that the reduced flooding frequency and magnitude as a result of river regulation may well be a major contributing factor in the species’ decline in the Murray‐Darling Basin.

A comparison of digital elevation models generated from different data sources

It can be challenging to accurately determine the topography of physically complex landscapes in remote areas. Ground-based surveys can be difficult, time consuming and may miss significant elements of the landscape. This study compares digital elevation models (DEMs) generated from three different data sources, of the physically complex Narran Lakes Ecosystem, a major floodplain wetland ecosystem in Australia. Topographic surfaces were generated from an airborne laser altimetry (LiDAR) survey, a ground-based differential GPS (DGPS) survey containing more than 20,000 points, and the 9″ DEM of Australia. The LiDAR- and DGPS-derived data generated a more thorough DEM than the 9″ DEM; however, LiDAR generated a surface topography that yielded significantly more detail than the DGPS survey, with no noticeable loss of elevational accuracy. Both the LiDAR- and the DGPS-derived DEMs compute the overall surface area and volume of the largest floodplain lake within the system to within 1% of each other. LiDAR is shown to be a highly accurate and robust technique for acquiring large quantities of topographic data, even in locations that are unsuitable for ground surveying and where the overall landscape is of exceptionally low relief. The results of this study highlight the potential for LiDAR surveys in the accurate determination of the topography of floodplain wetlands. These data can form an important component of water resource management decisions, particularly where environmental water allocations for these important ecosystems need to be determined.

A simulation framework for water allocation to meet the environmental requirements of urban rivers: model development and a case study for the Liming River in Daqing City, China

In this paper, we describe the development of a simulation framework for allocating water from different sources to meet the environmental flows of an urban river. The model permits the development of a rational balance in the utilization of storm water, reclaimed water from wastewater treatment plants, and freshwater from reservoirs with consideration of the limited capacities of different water resources. It is designed to permit the full utilization of unconventional water sources for the restoration of river water quality by increasing river flow and improving water quality. To demonstrate practical use of the model, a case study is presented in which the model was used to simulate the environmental water allocation for the Liming River in Daqing City, China, based on the three water sources mentioned above. The results demonstrate that the model provides an effective approach for helping managers allocate water to satisfy the river’s environmental water requirements.

The influence of changes to river hydrology on freshwater fish in regulated rivers of the Murray–Darling basin

Freshwater fish are often used as an indicator of the response of the ecosystem to the restoration of river flows or the provision of environmental flows. The ability to model the biological response of fish depends on the capacity to establish clear relationships between changes in river hydrology and the fish assemblages in a river. The fish assemblage structure and the abundances of individual fish species were examined in relation to a hydrological index that described hydrological change in six regulated rivers in the Murray–Darling Basin. The hydrological index explained only a small amount of variation in fish assemblage structure. In addition, the abundances of individual fish species were only weakly correlated with the index of flow deviation. It is suggested that these results make the modelling of responses of fish assemblages to environmental water allocations unfeasible at a large scale and that future studies should concentrate on potentially more simple responses, such as the relationships of fish spawning and recruitment to specific aspects of river hydrology.

The Collapse of Pelagic Fishes in the Upper San Francisco Estuary: El Colapso de los Peces Pelagicos en La Cabecera Del Estuario San Francisco

Abstract Although the pelagic fish community of the upper San Francisco Estuary historically has shown substantial variability, a recent collapse has captured the attention of resource managers, scientists, legislators, and the general public. The ecological and management consequences of the decline are most serious for delta smelt (Hypomesus transpacificus), a threatened species whose narrow range overlaps with large water diversions that supply water to over 25 million people. The decline occurred despite recent moderate hydrology, which typically results in at least modest recruitment, and investments of hundreds of millions of dollars in habitat restoration and environmental water allocations to support native fishes. In response to the pelagic fish collapse, an ambitious multi-hyphen;agency research team has been working since 2005 to evaluate the causes of the decline, which likely include a combination of factors: stock-recruitment effects, a decline in habitat quality, increased mortality rates, ...

Detecting impacts and setting restoration targets in arid‐zone rivers: aquatic micro‐invertebrate responses to reduced floodplain inundation

Summary Water extraction from arid‐zone rivers increases the time between floods across their floodplain wetlands. Less frequent flooding in Australian arid‐zone rivers has impaired waterbird and fish breeding, killed riparian vegetation and diminished invertebrate and macrophyte communities. Restoration currently focuses on reinstating floods to rejuvenate floodplain wetlands, yet indicators to measure the success of this are poorly developed. We explored the application of criteria for ecologically successful river restoration to potential restoration of floodplain wetlands on the Darling River, arid‐zone Australia. Using emergence of micro‐invertebrates from resting eggs as an indicator, we compared responses of taxa richness, densities and community composition in floodplain lakes with different inundation histories. Increased drying of floodplain lakes reduced the number of micro‐invertebrate taxa. Several key taxa were absent and faunal densities (particularly cladocerans) were reduced when the duration of drying increased from 6 to 20 years. A conceptual model of the ecological mechanisms by which restoration of flooding regime could achieve the target of preserving micro‐invertebrate community resilience predicts that reducing the dry period between floods will minimize losses of viable resting eggs. Protection of this ‘egg bank’ permits a boom in micro‐invertebrates after flooding, promoting successful recruitment by native fish and waterbirds. Synthesis and applications. In arid‐zone rivers, micro‐invertebrate densities and community composition are useful indicators of the impact of reduced flooding as a result of water extraction. Critical to successful native fish recruitment as their first feed and as prey for waterbirds, micro‐invertebrates are a potential early indicator of responses by higher trophic levels. Taxon richness, density and key taxa present after flooding, all indicators of resilience, can be incorporated into targets for arid‐zone river restoration. For example, one restoration target may be microcrustacean densities between 100 and 1000 L−1 within 2–3 weeks after spring flooding. These criteria can be applied to measure the ecological success of restoration projects seeking to recover natural flood regimes. Given the high economic cost of water in arid zones, convincing demonstrations of the ecological success of environmental water allocations are crucial.

A genetic algorithm-based fuzzy multi-objective programming approach for environmental water allocation

A fuzzy multiobjective-programming model was presented to determine appropriate environmental flow allocation in urban rivers. An integrated nonlinear fuzzy membership function, that represents a broader implication in fuzzy decision-making, was regarded as the general objective and genetic algorithm became an essential tool in search for the global optimal solution. A case study of optimal allocation for environmental water requirements in the Liming River Basin, Daqing, demonstrates the capability of the fuzzy multiobjective model based on fuzzy decision theories to work suitably in water environmental management in a river basin.

Plant Establishment from the Seed Bank of a Degraded Floodplain Wetland: A Comparison of Two Alternative Management Scenarios

There has been little research examining the soil seed banks of degraded floodplain wetlands and their contribution to wetland rehabilitation in Australia. Our aim was to assess the establishment of plants from the seed bank that may occur following the delivery of an environmental water allocation to Kanyapella Basin, a 2950 ha wetland located on the floodplain of the Goulburn and Murray Rivers in northern Victoria, Australia. Two hypothetical water regimes were investigated (flooded and dry) in a glasshouse experiment, where plants were left to establish from the seed bank over a period of 124 days. Differences in the establishment of plants from the seed bank indicated that the return of a flooding regime is likely to have a significant effect on the composition of the wetland vegetation. Mapping of the distribution of plant species indicated that propagules were highly dispersed across the wetland for the majority of taxa, in contrast to the localised distribution of many of the plant species represented in the extant vegetation. Inundation favoured the establishment of native wetland and floodplain plants, although many areas of Kanyapella Basin that are currently ‘weed-free’ have the potential to become colonised and potentially dominated by introduced plants if the wetland is not managed appropriately. Overall, results supported the aim of management to reestablish a wetting and drying regime through use of an environmental water allocation. This study presents a significant example of the application of seed bank investigations in wetland ecology and management.

Hydrology-based assessment of environmental flows: an example from Nepal

The paper examines the applicability of several desktop hydrology-based environmental flow assessment methods—Tennant, range of variability approach (RVA) and South African desktop reserve model (DRM)—in the specific context of Nepal. Some of these techniques are modified, following the discussion of their limitations. It is indicated that hydrology-based methods of environmental flow assessment represent a necessary first step in planning for environmental allocations in developing countries. It is shown that use can be made of complementary features of existing environmental flow assessment techniques to arrive at justified estimates of environmental flows, even in the conditions of limited basin-specific eco-hydrological knowledge. The methods described in the paper could also be used in other countries—by relevant departments, agencies and organizations, which are engaged in ecosystem management and preservation of aquatic environment. This research intends to promote the need for environmental water allocation planning in river basin development and to streamline the inclusion of environmental water demand assessments into relevant national policies.

Large, regulated forest floodplain is an ideal recruitment zone for non-native common carp (Cyprinus carpio L.)

Non-native common carp (Cyprinus carpio L.) are the most abundant large-bodied fish in the Murray–Darling Basin. The abundance of common carp larvae and young-of-the-year appears to increase after flooding, although the relative contribution of floodplain habitats compared to riverine areas remains unresolved. Larval nets were used monthly from September 2000 to January 2001 to identify common carp spawning and recruitment areas in the regulated Murray River and floodplain around the Barmah–Millewa forest. Five non-native and five native fish species comprising 136 111 individuals were collected, with common carp constituting 88% of the overall catch. Less than 1% of common carp, however, originated from the Murray River upstream of the Barmah–Millewa floodplain. Consequently, this floodplain appears to be a major source of common carp recruitment in the mid-Murray area. Conversely, eggs from large-bodied native fish were only present in the Murray River and not the Barmah floodplain. There are opportunities for common carp control in this area, to potentially reduce populations in a wider river reach. Implementation of common carp control measures in the Barmah–Millewa floodplain should be further investigated, particularly with regard to seasonal irrigation flows, obligatory migration routes and in the timing of future large-scale environmental water allocations.

Environmental flows allocation in river basins: Exploring allocation challenges and options in the Great Ruaha River catchment in Tanzania

Provision for environmental flows is currently becoming a central issue in the debate of integrated water resources management in river basins. However, the theories, concepts and practical applications are still new in most developing countries with challenging situations arising in complex basins with multiple water uses and users and increasing water demands and conflicts exemplified by the Great Ruaha River catchment in Tanzania. The research has shown that a flow of 0.5–1 m 3/s for Great Ruaha River through the Ruaha National Park is required to sustain the environment in the park during the dry season. But a question is how can this be achieved? This paper reviews the challenges and suggests some options for achieving environmental water allocation in river basins. The following challenges are identified: (a) the concept of environmental flows is still new and not well known, (b) there is limited data and understanding of the hydrologic and ecological linkages, (c) there is insufficient specialist knowledge and legislative support, (d) there are no storage reservoirs for controlled environmental water releases, and (e) there are contradicting policies and institutions on environmental issues. Notwithstanding these challenges, this paper identifies the options towards meeting environmental water allocation and management: (a) conducting purposive training and awareness creation to communities, politicians, government officials and decision makers on environmental flows, (b) capacity building in environmental flows and setting-up multidisciplinary environmental flows team with stakeholders involvement, (c) facilitating the development of effective local institutions supported by legislation, (d) water harvesting and storage and proportional flow structures design to allow water for the environment, and (e) harmonizing policies and reform in water utilization and water rights to accommodate and ensure water for the environment.