The CWA engaged highly regarded ecologist Paul Boon to produce the report which draws together the contemporary ecological thinking on necessary widths for waterways corridors. These corridors are the threads that connect together a healthy landscape. We need them. They enable waterways to function as living entities. And they need to be of adequate width. This report tells what minimum necessary widths we need to consider for the functions prescribed in policy and legislation for waterways.
2024 Climate Change and Estuaries Kennish et al 2024 preview
The introduction to the book, Climate Change and Estuaries edited by Michael J. Kennish, Hans W. Paerl and Joseph R. Crosswell. Also contains 164 page bibliography.
2023 The influence of geomorphology and environmental conditions on stratification in intermittently open/closed estuaries
Large changes in stratification occur as water drains from the estuary to the ocean potentially leading to a loss of of the top oxygenated layer of the water column during drainage which can cause fish kills. This study could be useful for estuary managers to predict how stratification in different types of Intermittently Open/Closed Estuaries will change during artificial openings and provide a proxy for predicting their response to climate change.
2023 Karaaf Wetlands Estuary Mouth Assessment
This review tested the assumption that keeping the Thompson Creek estuary in an open condition would improve flushing of the wetland to the west of Point Impossible Road and assist recovery of the impacted saltmarsh vegetation. Overall, the conclusion of this review is that opening of the estuary will not mitigate the effects of increased stormwater inflows on the Karaaf wetlands to the west of Point Impossible Road.
2021 Assessment of Victoria’s estuaries using the Index of Estuary Condition: Results 2021
The Index of Estuary Condition (IEC) framework was developed to provide a consistent and systematic measurement of estuarine condition in Victoria for the purposes of:
- Reporting on estuarine condition to communities
- Guiding state policy and regional planning of estuary management
- Providing a benchmark for estuary environmental condition.
2021 Water management from basin to biofilm by Krista Bonfantine
An assessment of biotic indicators of stream health and the impact of summer flow pulses from the Painkalac Reservoir on the condition of Painkalac Creek, downstream of the reservoir. Across all biological, biochemical and physical data analysed, the only significant change produced by environmental flow pulses in Painkalac Creek was an altered thermal regime resulting from warm water released from the reservoir.
2020 Variability in infragravity wave processes during estuary artificial entrance openings
This study utilises artificial entrance openings of multiple Intermittently Open/Closed Estuaries in Victoria, Australia, to capture continuous hydrodynamic and geomorphic data throughout the opening cycle. We illustrate that water level oscillations in the infragravity (IG) band) are present in the basin during open entrance conditions. Our work identifies that changes in cross-sectional area, bed depth at the berm position, and offshore wave height control the magnitude of IG waves within the estuary basin.
2020 Field observations of geomorphic change during artificial openings
A dataset that enables us to understand what changes in entrance morphology occur during an opening and how these changes affect the rates of basin drainage. Findings: Calculating the hydraulic gradient is a cost-effective and easy way to assess the likely success of artificial openings. Ultimately this will reduce the need for reimplementation. The hydraulic gradient can also be used to predict drainage rates and determine when natural openings are likely to occur.
2020 The Effect of Mouth State and Morphology on Stratification in Victorian Estuaries
The results have identified, for the first time, the change in stratification that occurs during entrance openings and how these changes vary between openings of different magnitude. These results have also linked changes in stratification to changes in mouth morphology during the draining phase. Importantly, changes in morphology at the mouth are affected by (1) the timing of the artificial opening and (2) the initial channel dimensions. These variables can be easily manipulated by estuary managers. By having better control of the magnitude of the opening, large drops in Dissolved Oxygen can be prevented, preventing mass fish deaths.
2018 Predicting the entrance opening duration of Intermittently Open/Closed Estuaries (IOCE) in Victoria
This study uses historical records of entrance state and marine and fluvial conditions to develop a method of predicting the opening duration. The outcome is a predictive tool that managers can use to input both the current and forecast conditions to determine the probable entrance opening duration. This method will form a decision support tool for estuary entrance management that will have the capacity to learn and improve in future.
2017 The daily-scale entrance dynamics of Intermittently Open/Closed Estuaries
In this study, the entrance dynamics of three Intermittently Open/Closed Estuaries on the coast of Victoria, Australia, are monitored over a daily timescale following both artificial and natural openings. The influence of changing marine and fluvial conditions on the relative sedimentation rate within the entrance channel is examined. Based on the findings of this work, implementing a successful artificial entrance opening is dependent on reduced onshore sedimentation rates which occurred when wave energy is low (< 2 m Hs) relative to river flow.
2016 Watering Proposal for Painkalac Creek
The scope of this report was to determine the most appropriate watering actions for Barwon Water to implement, that make best use of the additional water now available in the Painkalac reservoir. These watering actions specifically detail potential flow releases from the reservoir that benefit key ecological parameters of the creek and consider the specifics of the system as well as its limitations.
2015 A review of Australian approaches for monitoring, assessing and reporting estuarine condition: II State and Territory programs
A systematic appraisal of current and impending approaches for measuring and reporting estuarine condition in each of Australia’s States and Territories. A concise summary is provided in each case, supported by extensive appendices containing detailed accounts of relevant monitoring and reporting programs. We synthesise and evaluate this output at the State/Territory level, highlighting areas of improvement and major gaps.
2015 Victorian Index of Estuary Condition: Implementation Trial Final Report
The results of a trial of the recommended Index of Estuary Condition (IEC) methods involving field sampling in 55 estuaries and scoring in 40 estuaries (including the Painkalac) with individual estuary scores included in the appendices
Painkalac Creek Estuary 2015: An interpreted summary of data
2014 Freshwater influences on hydrology and seagrass dynamics of intermittent estuaries
Influences of natural and hydrological variability on seagrasses were examined in the Anglesea and Painkalac estuaries. Seagrass expansion is associated with perods of drought and extended mouth closures while floods and open estuaries led to a reduction in the seagrass extent in both estuaries.
Painkalac Creek Estuary 2007-2013: Data analysis and interpretation
2013 Painkalac Creek Flood Study
The Corangamite Catchment Management Authority has completed a detailed hydrological study of Painkalac Creek catchment to determine design flow estimates for the hydraulic floodplain modelling of Airey’s Inlet. This work forms the basis of new flood overlays to be introduced into the Surf Coast Shire Council Planning Scheme.
2009 Victorian index of estuary condition: recommended themes and measures
A study to develop an Index of Estuary Condition for evaluating the environmental condition of Victorian estuaries. This will complement the existing index of Stream Condition to better enable:
- Estuarine condition to be reported at regional, state and national levels.
- Prioritisation of resource allocation.
- Strategic evaluation of management interventions in estuaries.
2007 Environmental Flow Determination for Painkalac Creek
An issues paper proposing eight environmental flow objectives and for each objective the types of flows required have been determined. These include the flow component (low flow, high flow, flood flow), time of year, the frequency (if known) and the duration (if known). For each flow type, criteria for assessment have been developed (e.g. depth of water required to allow fish passage for certain species, velocity of water to prevent water quality decline in pools).
2006 Freshwater Influences on Hydrology and Seagrass Dynamics of Intermittent Estuaries
Influences of hydrological variability on physico-chemical conditions and seagrasses were examined in two central Victorian estuaries (Anglesea and Painkalac) with anthropogenically-modified, but naturally-intermittent, freshwater flows and mouth openings. A three-state conceptual model of the magnitude and variability of estuarine water levels, based largely on the degree of tidal influence was identified (with states being defined as either closed, perched or tidal). Analysis of historical patterns of seagrass extent against rainfall records suggested that periods of drought and extended mouth closures were related to establishment and expansion of seagrass beds. The results could inform management of flow and inundation regimes to avoid or minimise unnatural losses of seagrass or to maintain water quality at times of highest risk.
1996 Waterbirds on a small estuarine wetland – a six year study
Bird species and numbers on a small estuarine wetland in south-western Victoria were recorded for six years from 1990 to 1995 inclusive. Observations were made by telescope at least once daily and the maximum number of
birds was recorded each half-month. Note was taken of the water level. Some seasonality and a preference for low to medium water levels was shown. This permanent wetland is important for its aesthetic value, as a foraging area
and as a refuge in times of drought.