Acknowledgements We would like to thank the following people for their contributions to the creation of the Currumbin Creek Catchment Study Guide.
Thanks to:
Paul Evans – Somerset College
Paul Wotton – Hillcrest Christian College
Shannon McKiernan – Gold Coast City Council
Staff of the Gold Coast City Council’s Catchment Management Unit
The host of teachers involved in the Gold Coast Waterwatch Program over the past 4 years
Preface The Currumbin Creek Study Guide is a Gold Coast Waterwatch initiative designed to assist students and teachers to undertake local area and catchment management studies. The guide is designed primarily for use by secondary school students and teachers, particularly those undertaking studies within the Studies of Society and Environment, (SOSE), and the Science curriculum.
However, it is recognised that a range of other curricula areas utilise local areas in their delivery and the structure and content of this guide has been developed to accommodate these needs. In particular, the needs of various science curricula are noted as of major importance for use and uptake of this resource.
Information used in the development of this guide is diverse and has been sourced from: • Gold Coast City Council – Catchment Management Unit • Gold Coast City Council – Libraries • Gold Coast City Council – Local Area Studies • Griffith Centre for Coastal Management • Waterwatch Australia • Waterwatch Queensland • Waterwatch Victoria • Waterwatch South Australia • Healthy Waterways • GECKO (Gold Coast and Hinterland Environment Council Association) For further details, a list of resources and references is provided in this guide.
This guide is provided in four sections –
• Background/catchment information
• Testing and field monitoring information
• Field trip or in-class uses for the guide
• Resources, glossary and maps
Each of these sections can be viewed independently, however it is recommended that sections be reviewed and considered as part of the whole.
What’s in this Guide?
Catchment Information ______7
What is a Catchment? ______8
General Description of the Currumbin Creek Catchment______9 Looking at Currumbin Creek - Cross Sections ______11
History of Land-use and Catchment Management ______14
Influences on the Catchment Health and Water Quality______15 Stormwater ______16 Urban Development ______18 River Mouth Structures and Dredging ______19 Water Barrage and Other Impediments ______21
Water Quality Measurement ______23 Field Data ______24 Macro-Invertebrates ______25 Habitat Assessment ______31 Physio-Chemical Tests ______34
Using the Guide and Developing Catchment Study Programs 43 Links to Qld Curriculum______44 Studies of Society and Environment (SOSE) ______44 Science Syllabus______44 Sample Discussion Points by Theme______45 Sample Catchment Tour ______46 Itinerary______46 Activity/Data Collection Sheets______48 Macro-Invertebrate Record Sheet______51 Physio-Chemical Record Sheet ______53 Weather______53
References and Resources ______55 Books and Publications______56 Internet Sites______56
Glossary ______57
Maps ______58 Planning Scheme Maps ______58 Topographical Maps of Interest ______58
Catchment Information
What is a Catchment?
A catchment is an area or basin of land bounded by natural high features such as hills or mountains from which all run-off water flows to a low point like a stream or river or the sea – like water in a bathtub flowing to the plug hole or water that falls on a roof flowing to a downpipe. So, under the influence of gravity, rain falling on the land flows from the top of the catchment through a network of waterways, from small gullies and streams and into larger rivers, to the bay. Healthy Waterways (2003) Fact Sheet 3 – What is a Catchment, www.healthywaterways.org
As described above, a catchment is a natural basin in which all water flows to a central point. In the Currumbin Creek Catchment, that point is the ocean at ‘The Alley’, with the main transport route being Currumbin Creek.
Catchments are often classified into different sections as a result of the types of waterways present and the roles that they play. The smallest waterways are referred to as Level One Streams. These ‘streams’ are often only gullies or drains that carry water after rainfall events. Level Two Streams connect the gullies and drains to major waterways. These are often considered to be tributaries of major waterway. The Currumbin Creek Catchment is unusual as it has very few Level Two Streams due to its narrowness and small land area.
Fig. 1.0 General overview of a catchment area
General Description of the Currumbin Creek Catchment
Currumbin Creek Catchment is located of the southern end of Queensland’s Gold Coast. The catchment is sandwiched between Tallebudgera Creek Catchment to the North and Tweed River Catchment to the South. The catchment is bound to the West by the eastern edge of the Nerang River Catchment in the Gold Coast Hinterland.
The Currumbin Creek Catchment is approximately 23 km long and flows into the Pacific Ocean at ‘The Alley’, between Currumbin Beach to the South and Palm Beach to the North. The land area of the catchment is calculated to be approximately 5,203 Ha and the population estimated to be up to 19,000 people.
Currumbin Creek has no major tributaries, only small ephemeral creeks and drains along the length of the waterway. In the urbanised areas, many of the natural creeks and drains have been replaced with development of stormwater networks.
Land-use within the small catchment is diverse with significant areas of: • Natural protected areas • Grazing/agricultural areas • Urbanisation and settlement (including acreage, large allotment, suburban allotments, artificial canal development, and medium density living) • Commercial and business areas • Recreational/tourism based development “The Valley to The Alley” describes the distribution of land-use as being ‘perfect’, with approximately 1/3 protected and/or wilderness areas, 1/3 agro-forestry (described as sustainable timber and agriculture activities) and the remaining 1/3 comprised of traditional agriculture, industrial, commercial and urban land-uses.
Fig. 1.1 Overview of Currumbin Creek Catchment
The upper catchment is located within the Mt Cougall National Park. Runoff then flows through encroaching adjacent rural and farming areas, (banana plantations and dairy farming). Land-use within the middle region of this catchment has been modified to
accommodate rural residential development. Large areas of the lower catchment have been cleared for urban residential development. Riparian vegetation in this area of the creek has been lost or is under pressure from the development activities.
At the centre of the Currumbin Creek catchment is Currumbin Creek. Currumbin Creek is a modified River Dominated Estuary. Historically, the entrance to Currumbin Creek opened and closed according to rainfall and seasonal influences. However, since the increased development within the catchment, the desire for constant ocean access by residents and the need to protect property against potential flooding, structures have been introduced to maintain the river opening. This has resulted in significant change to the physical structure of the estuary and the associated water quality measures.
The middle regions of this creek are freshwater habitats, consisting of a shallow creek with deep pools and infrequent riffles. These regions are said to support localised platypus populations. The upper reaches are relatively undisturbed in the protected areas, however, significant clearing of riparian vegetation has occurred in the agricultural areas in the past. This has lead to the establishment of significant camphor laurel communities, a declared weed species that would require some removal process.
Today, the estuary is considered to be of moderate to good quality. This assessment of the health of the waterway is supported by a number of sources including: • Gold Coast Waterways Freshwater Fish and Aquatic Habitat Survey • Gold Coast City Council’s Health of the Waterways 2002 • Healthy Waterways “Discovering the Waterways of South East Queenslan
Looking at Currumbin Creek - Cross Sections Currumbin Creek flows from the top of the catchment to deposit water into the ocean at ‘The Alley’. Throughout this journey a number of typical and specific environments are encountered and are described below.
Upper Catchment – Relatively Undisturbed
Fig. 1.2 Upper Catchment of Currumbin Creek
The very upper catchment of Currumbin Creek is characterised by well wooded banks, good instream cover and structure. The water quality is very good in this region as it is within the protection of Mt Cougall National Park.
Upper Catchment – Cleared for Grazing/Acreage Living
Fig. 1.3 Downstream of Upper Catchment Area
Down stream of the protected areas, well wooded banks give way to pasture and cleared ground. Soil surface is typically covered by vegetation, generally exotic grasses, in-stream cover and structure generally remains. Overall water quality is still medium-good in these areas, however elevated nutrient levels are sometimes experienced in testing. The clearing of the bank sides has lead to an invasion from the exotic and declared weed species camphor laurel.
Common land-use in this area is small scale agriculture, (dairy), and small/medium acreage living.
Salt Fresh Mixing Zone – Extent of the Tidal Influence
Rock Barrage High Tide Tidal Movement Low Tide Shallow Mixing Zone Tidal Creek
Fig. 1.4 Small Rock Barrage
The intrusion of salt water into Currumbin Creek is limited by a small rock barrage located at the western end of the lake, west of the intersection of Currumbin Creek Road and Bourke-Lodge Drive.
These structures provide barriers not only to the movement of the estuary waters but also to the movement of fish and other aquatic species.
Upper Estuary – Increasing Urbanisation
Fig. 1.5 Upper Parts of Currumbin Creek Estuary
In the upper parts of the Currumbin Creek Estuary (salt water component of the creek), urban dwellings and cleared road reserves front the creek banks. While the bank side vegetation remains, much of the riparian zone has been cleared, removed and/or modified.
Stormwater has an increasing impact on the water quality and range of inputs affecting the creeks composition.
Estuary – Modification and Urbanisation
Fig. 1.6 Lower reaches of the Currumbin Creek Estuary
In the lower reaches of the Currumbin Creek Estuary, impacts from urbanisation increase. Almost all of the riparian vegetation has been removed or modified, as has much of the bank side vegetation. Significant modifications have occurred to the creeks structure with the inclusion of canal living and dense urbanisation.
The impact of stormwater and other overland flows is increasing, with greater areas of hard paved materials and other drainage modifications. The stormwater quality is reduced with the impacts from road, household and light industrial land-use.
Ocean Outfall – Lowest Point of Catchment
Fig. 1.6 Mouth of Currumbin Creek
At the mouth of the Currumbin Creek, many modifications have occurred. Rock training and retaining walls have been added at the north and south sides of the river mouth to keep it open and influence sand movements. Rock walls have also been added to the banks to eliminate erosion from tidal and flood movements.
Impacts on the water quality arise from a range of sources including recreational uses, visual amenity, dredging, stormwater, urban development, stream modification and tidal flow.
Limited bank side vegetation is protected by a wetland reserve on the northern bank of the creek.
History of Land-use and Catchment Management
European settlement began in 1860’s, significant urbanisation in late 20th Century, 1970 onwards
Timber gathering peaks in 1900’s, 20-30, 50’s
Dairy 1880’s till present, peaked in the 1940’s legacy of pasture grasses
Tourism with rail in 1900’s, very popular, with 1st public toilet in 1914
1912 Banana plantations with peak in 1930’s
1912 - Sandmining at beach until 1947 when moved inland
1973 - River mouth modification – permanent opening and dredging
1 1 1 1 1 2 8 9 9 9 9 0 7 0 2 5 7 0 5 0 5 0 5 0
The timeline demonstrates the diverse land-use in the catchment over a relatively short time period. Many of the land-use activities have had a high impact on the local environments. The short history of the banana industry, (relative to its peak, although bananas are still farmed in the catchment today), is a prime example of a high impact industry. Not only was land cleared to cultivate the bananas, but intensive timber gathering was also undertaken to supply boxes to transport the bananas from the valley to market. As a result, significant areas of non-cultivated land were also impacted by the banana industry. It must be noted that land clearing associated with banana cropping is comprehensive. It is said the entire southern bank of Currumbin Creek along the walking track in Mt Cougall National Park is regrowth, as the banana plantations in the 1920’s and 1930’s completely cleared the hillside of significant vegetation.
The timeline also notes the longevity of industries in the catchment. Agriculture and dairying still exist to some extent. Historical reports note tourism as a major industry and driver of development in the catchment from the 1910’s onwards. The introduction of the railway in 1902 provided access with the natural beauty of the area attracting high numbers of visitors. Major tourist facilities, (and associated retail and industry), exist today with examples like Olsen’s Bird Gardens, the Currumbin Rock Pools and the numerous accommodation and recreational facilities.
Influences on the Catchment Health and Water Quality
Like all catchments on the Gold Coast, there are a range of general and specific issues influencing the water quality and general health of the catchment. The issues threatening or negatively impacting water quality are referred to as ‘pressures’. A range of general pressures on water quality and catchment health on the Gold Coast include: • Stream and water flow barriers • Waterway modification • Urbanisation and industrialisation of catchment areas • Riparian vegetation loss • General vegetation loss • Stormwater quality and movements • Impacts from weed species • Impacts from introduced animals • Erosion and sedimentation • Point source pollution • Increased nutrient levels All catchments on the Gold Coast are placed under some degree of pressure by a range of the above factors. However, all the waterways on the Gold Coast are relatively protected by a range of catchment management strategies and historical settlement and development.
In this guide, four issues have been identified for specific discussion. These include general catchment related issues as well as issues more specific to Currumbin Creek Catchment, including: • Stormwater • Urbanisation and Canal Development • River Mouth Structures and Dredging • In-stream Barriers to Water-flow
Stormwater Stormwater is rainwater plus anything the water carries along with it. In urban areas, rain that falls on the roof of houses, or collects on paved areas like driveways, roads and footpaths is carried away through a system of pipes and drains that is separate from the sewerage system. Unlike sewerage, stormwater is not treated.
Fig. 1.7 Various Stormwater Quality Improvement Devices (SQIDS)
In some cases stormwater is filtered by Stormwater Quality Improvement Devices (SQIDS), but still flows directly from streets and gutters into the creeks, rivers, and the ocean. Every time it rains, oils, detergents, paints, pesticides, fertilisers, grass cuttings, animal wastes and soil from backyards are washed down street drains, through the stormwater system and discharged into rivers, creeks, canals and the ocean.
The stormwater system is designed to minimise flooding and safely clear water from urban environments. To complete this process, the system must be capable of moving large volumes of water in very short timeframes, while minimising the impact on the receiving environments. As a result, the stormwater system carries relatively large particles with ease when the water is flowing. Litter for example, can be transported large distances and deposited directly into a range of environments, such as Currumbin Creek. This process works equally for any other chemical and physical pollutants.
Additionally, the role stormwater plays in clearing large volumes of water results in less water soaking into the ground, and more water being moved into the rivers. Swamps and other wetland areas provide recharge zones for ground water while
filtering many of the large sediments and other particles from runoff water. As more areas are drained by stormwater systems, there are fewer opportunities for infiltration and filtering. The physical characteristics of the Currumbin Creek Catchment mean that large wetland areas did not exist and therefore were not removed by increasing stormwater, however smaller local recharge areas are influenced by the stormwater system.
In other areas on the Gold Coast, the Gold Coast City Council is constructing artificial wetlands as well designing stormwater solutions for urban environments. Combined, with the inclusion of SQIDS, this will result in a reduction of the negative impacts arising from the increased nutrient, sediment, pollutant and litter levels that are associated with the development of stormwater protection systems.
The quality of stormwater is generally lower than that in the natural environments. Stormwater flows throughout urban areas and drains urban infrastructure like roads. As a result, the waters often carry significant pollution loads which are commonly high in turbidity, nutrients, detergents and oils. These pollutants are in addition to gross pollution resulting from litter and organic matter.
Urban Development Development within the Currumbin Creek Catchment has been occurring in some form since the 1860’s. However, the dense urban developments observed in the catchment today are much more recent, occurring generally since the 1970’s.
The significant rate and extent of development (both urban and commercial) in this period results in a number of pressures on the broad environmental and specific water quality health of the catchment. As development occurs increased areas of land surface are covered by hard, impermeable structures such as roads, paths, buildings and other forms of pavement. All reduce the amount of water that soaks into the ground and increases the volume of movement in major storm events.
Additionally, the extent of development has resulted in the loss of much of the native vegetation and, in particular, riparian vegetation in the lower half of the catchment. The significant loss of vegetation has resulted in loss of structural support for the banks of the waterway. Furthermore, the removal of vegetation has resulted in the loss of habitats and important ecosystem linkages across the catchment.
To help minimise these problems into the future, a Catchment Management Plan is being developed for the area. The new Gold Coast Planning Scheme “Living City” has identified a range of permissible activities for specific areas within the catchment based on broad environmental health and community needs. Other planning linkages have developed through the adoption of specific Local Area Development Plans within the catchment.
Fig. 1.8 Currumbin Waters – Canal Development
River Mouth Structures and Dredging Historically, the entrance to Currumbin Creek has been variable with the sand and water flows causing the mouth to close regularly. The rocky outcrop at the mouth of Currumbin Creek was not always the headland that is now observed. It is only since the construction of the rock wall connecting the car park to these rocks in 1973, that this rocky outcrop became a permanent headland structure at the mouth of the creek. Previously, sand was free to move between these rocks and the main land, (the carpark at the base of the hill), as a result of tidal flows, seasonal changes and storm events. Consequently, the creek mouth’s structure and location were regularly changing.
The rockwall was constructed to ensure that the creek mouth would not be closed by northerly sand movements, ensuring flow in the creek to protect against flood and to service the canal living developments in the catchment. Once constructed, the retaining wall altered the flow of sand at the mouth of the creek and subsequently the sand movements on adjacent Palm Beach. This resulted in changes to amount and rate of sand replenishing the beach.
Further structural development was undertaken in 1980, where the retaining wall was constructed on the northern arm of the creek mouth. The wall was designed to prevent any northerly movement of the creek mouth, (thus reducing erosion to southern Palm Beach), and to limit possibilities of closure of the creek mouth that would impact on recreation and flood mitigation programs.
Training Wall - 1973
Northern Retaining Wall - 1980
Palm Beach
Currumbin Creek
Fig. 1.9 Structural Development
Dredging, as well as the development of structures at the mouth of Currumbin Creek has been undertaken over a number of years. Sediments are deposited in the mouth of the creek from two main sources: 1. sediments flowing down the creek (very minor) 2. ocean sand movements (major) Dredging is undertaken for a number of reasons which include: • ensuring an unimpeded flood flows/drainage • providing a sand source to nourish Palm Beach (see attached figure) • providing and maintaining visual and social amenity • ensuring safe movements and navigation for boat traffic
The dredging of the river mouth maintains a constant ocean opening while fulfilling a need to balance sand movements on the Gold Coast. This aids in protecting Gold Coast Beaches from severe erosion and degradation, (see images of Palm Beach).
Dredging of Currumbin Creek yielded approximately 600,000m3 of sand to replenish Palm Beach between 1974-1981, (ie; prior to the construction of the of the northern retaining wall). Since this time, additional dredging has continued with the approximate dredging volumes presented in the table below.
Approximate Dredging Volumes from Currumbin Creek Year Volume (m3) Seawall constructed 1974/1975 148 450 1976/1977 111 325 1978/1979 124 000 1979/1980 153 470 1980/1981 57 000 Training wall constructed 1981/1982 300 000 1983/1984 48 850 1984/1985 No dredging undertaken 1985/1986 90 000 1986/1990 No dredging undertaken 1990/1991 40 000 1991/1992 70 000 1992/1993 65 000 Dredging continues in the estuary as required, with as much as 300,000m3 of sand being removed in the eight months prior to June 2002.
1967
1974
2000
Fig. 1.10 Dredging over the years
Water Barrage and Other Impediments Physical structures within the waterway impede natural water flows. These structures can take many forms from large dams, such as the Hinze Dam in the Nerang River Catchment, to small culverts and road crossings, such as the one at the entrance to Mt Cougall National Park in the Currumbin Valley. Each of these structures was designed to serve a specific purpose. However, their physical presence also has a range of additional impacts on the waterways and their health.
The construction of structures within the waterways such as culvert, barrages and dams will effect a range of physical, biological and chemical components of a waterway. The most obvious is the reduction and modification of water flow. This will often result in ponding upstream of the structure and higher flow rates directly below the structure. The greatest impact this has on the waterway is through the changes to the physical environments. Areas are flooded and the ponded water is deeper and cooler than that which may naturally occur. This generates a new habitat, ideal for plant and animal communities different from those that existed in the same spot previously. However, generally speaking, these communities adapt to these changes by changing their composition and new communities develop.
Some of the more long term impacts of these structures on the waterways occur when the structures stop the natural in-stream migration and movement of organisms, (for example; fishes) or change in the water composition. A clear example of such a structure on Currumbin Creek is the barrage west of the lake at the intersection of Bourke Lodge Drive and Currumbin Creek Road. This weir or barrage was constructed to supply fresh water to domestic/agricultural needs in the catchment and it now represents the extent of tidal flow within the creek. The weir acts a major barrier to migratory fish species and impacts the extent of salt mixing throughout the catchment. As a result, the weir limits the opportunity for the development of a brackish water zone within the creek, by artificially limiting the extent of salt water mixing and infusion in the catchment.
Fig. 1.11 Lake on the low side of the weir – area of salt and fresh mixing
Measuring Water Quality
Field Data
Developing information on water quality and environmental parameters can be accurately undertaken by anyone. However, care must be taken to collect data that is relevant to the study, is appropriate for the equipment available, is appropriate to the skill level of the participant and can be interpreted and understood by the participants.
There are three main methods for assessing the water quality of a waterway.
1. Biological assessment – macro-invertebrate sampling
2. Biological assessment – riparian zone survey
3. Physio-Chemical testing
These three approaches can be used independently or in combination depending on the needs of the participants. All of these testing approaches seek to address questions on the environmental health of a waterway. None of the test approaches, as described in the Guide, are designed to answer questions such as, “Can you drink this water?”.
Before any field testing is undertaken issues of safety, environmental protection and consideration for others must be addressed. Safety • Never test alone • Always choose a test site that provides safe access to the water • Carry drinking water • Be aware of areas that may flood without warning • Limit entering the water to less than knee deep and always wear appropriate footwear • Be aware of test chemicals and take appropriate precautions when handling these chemicals • Be observant and aware of hidden objects or dangers including holes, snakes or electric fences Environmental • Always dispose of used test chemicals and samples responsibly, (eg; in waste containers) • Do not litter • Avoid damaging verge, bank-side and in-stream vegetation and structures • Return macro-invertebrate samples to the water as quickly as possible to limit harm, injury or death to these creatures Courtesy Considerations • Do not enter private property without permission • Do not climb, stretch or move fences • Leave all gates as you find them
Macro-Invertebrates Macro-invertebrates are very useful indicators of water quality and environmental health of a waterway. As a collective group, these creatures fill a central roll in the food chain of the waterway. In many cases they live in the water for more than a year and they cannot escape impacts of pollution. Therefore their presence represents water and habitats of sufficient quality to sustain a diverse range of life cycle needs. Food Chain
Macro-invertebrates fill each of the levels within the food chain in aquatic environments.
carnivores
omnivores omnivores detritivores omnivores SUNLIGHT
herbivores herbivores herbivores herbivores herbivores Primary production by green plants and algae
Fig. 1.12 Macro-invertebrates food chain Life Cycle
Macro-invertebrates are divided into a range of species and family groupings as well as representing a range of stages of lifecycle development for creatures. For example, a cadis fly larvae may be considered the 3rd stage in a four-stage life cycle for the creature.
FLY
EGGS
PUPA/ LARVAE EMERGENT
Fig. 1.13 Life cycle of a cadis fly
Each of these life cycle stages will require specific environmental conditions and have specific tolerances. As a result, some creatures have a very narrow range of environmental conditions in which they will survive and thrive. The range of environmental conditions in which an organism can thrive will be determined by its sensitivity to changes in water quality. Creatures that require very narrow ranges of environmental conditions are generally considered to be very sensitive to changes in water quality, while creatures that survive a wide range of water quality conditions are considered to be tolerant of most changes. These differences provide a measure of water quality based on the types and numbers of creatures observed in the water.
Macro-invertebrates are ideal as indicators as they can be seen by the naked eye, are very diverse, fill most ecological areas and cannot limit exposure to water quality issues, (eg; fish can escape some water quality problems). Macro-invertebrate Sampling
Macro-invertebrate sampling can be undertaken without complicated equipment. A pool scoop, ice cube trays and a magnifying glass are enough to sample and examine aquatic macro-invertebrates.
Water bugs live in a variety of habitats within the waterway. So when sampling, a variety of in-stream habitats must be included where possible. To do this, the sample should be taken from a combination of areas of rocky bottoms, areas of steep banks, areas with water plants in the stream and areas where plants grow out of the water. These areas should be sampled by sweeping the net upstream, touching and disturbing the banks, bottom and vegetation with the edge of the scoop. The creek or stream should be sampled for 2 minutes or a length of 10m of scooping. However, it is advisable to take several sweeps within this time/length period so as to collect the bug samples in smaller lots. Trying to collect one large sample will result in losing many of the macro-invertebrates and other organisms back into the water.
Once collected, the sample net should be emptied onto a large tray or similar. From here, sort the live bugs into smaller trays, (eg; ice cube containers), with paintbrushes or similar implements (Note: tweezers will crush many of the delicate creatures). More detailed identification can be undertaken in the smaller trays. Identifying the Macro-invertebrates
Use the following images or for more information contact the Waterwatch Coordinator to access detailed bug identification materials.
Stone Fly Nymph Sensitivity Rating 10 Note 2 tails and 2 pairs of wing pads.
Very Sensitive Macro-invertebrates
Sensitive Macro- invertebrates
Riffle Beatles Sensitivity Rating 8 Adults less than 4mm black or dark brown, larvae (grubs) less than 5mm and torpedo shaped
Caddis-fly Larvae Sensitivity Rating 8 3 pairs of legs below head, build/ collect homes from sticks, sand, leaves.
Mayfly Nymphs Sensitivity Rating 8 3 tails, short antennae and lateral gills on abdomen.
Medium Tolerance Macro-invertebrates
Damselfly Nymphs Sensitivity Rating 4 3 leaf like tails, short antennae, large eyes - hunters.
Water Mite Sensitivity Rating 6 Small, pinhead to 4 mm, with 4 pairs of legs.
Water Strider Sensitivity Rating 4
Dragon Fly Larvae Sensitivity Rating 4
Fresh Water Shrimp Sensitivity Rating 4
Tolerant Macro-invertebrates
Diving Beatles Sensitivity Rating 3
Back Swimmer Sensitivity Rating 2
Very Tolerant Macro-invertebrates
Freshwater Worms Sensitivity Rating 1
Using the Information There are many ways to interpret the information about the types and numbers of Macro-Invertebrates collected. These range from the scientific signal index approach which utilises species richness measures and tolerance ratings, to simple tolerance rankings. At the core of any of the interpretation techniques is the rule that the greater the diversity of creatures observed the more likely the health of the waterway is high. The second assumption is that very sensitive creatures will not occur in large numbers in low water quality waterways. Whilst remembering these two basic assumptions, it can simply be said that creatures of high sensitivity indicate higher water quality. Simple Tolerance Method Dominant Group 2 Very Very Tolerant Medium Sensitive Tolerant Sensitive Very Degraded – Good- Degraded Poor Medium Tolerant Poor Medium Degraded – Good - Tolerant Poor Poor Good Poor Medium Medium - Medium Poor Poor Medium Good Good
Dominant Group1 Sensitive Medium Medium Good Good Excellent
An understanding of the causes of lowered water quality can also be developed from the types of bugs observed. The table below indicates some of these connections. You Find . . . . . it suggests Little variety of organism types, with Water overly enriched with selective large numbers of each pollutants such as organic matter Only one or two organisms in large Severe organic pollution numbers A variety of organisms, but only a few Stream may have undergone flooding or of each or no organisms but the scouring stream appears clean No animals Toxic pollution
Habitat Assessment The health of the habitat surrounding the waterway has a direct relationship with the water quality. When surrounding habitats are poor, it is generally found that water quality is also poor. The role of the surrounding habitat in maintaining water quality is very important. These communities filter inflow run off, support a diversity of life, and provide physical protection from large changes in temperature or from significant erosion or sedimentation. Conducting Habitat Surveys A habitat survey involves observing the vegetation and physical condition of the waterway and surrounding environments. Ideally, the survey is conducted over a 100 metre length of the waterway on both banks, (ie; 50m upstream and 50m downstream from test site). However, this is commonly not possible. So the length of the survey area should be noted in the survey, remembering the longer the survey area, the more accurate the result. Five habitat indicators are observed in the survey: 1. Bank vegetation 2. Verge vegetation 3. In-Stream cover 4. Bank erosion and stability 5. Riffles, pools and bends (in stream diversity)
Trees Woody Shrubs
Herbs Grass
Floating Verge Vegetation Bank Vegetation Emergent Submerged
Riparian Zone Aquatic Zone
Fig. 1.4 Habitat Survey
Assessing Habitat Surveys
Excellent Good Fair Poor Very Poor Bank Vegetation (10) (8) (6) (4) (2) Mainly undisturbed Mainly native Medium cover, Introduced ground Introduced ground native vegetation. vegetation. little mixed native/ cover, little native cover with lots of No signs of disturbance or no introduced. Or one under or over- bare ground, alteration. signs of recent site side cleared, the storey, occasional tree. disturbance other undisturbed. predominantly Also includes sites introduced with concrete lined vegetation. channels.
Verge Vegetation (10) (8) (6) (4) (2) Mainly undisturbed Well-vegetated Wide corridor of Very narrow Bare cover or native vegetation on wide verge corridor. mixed native and corridor introduced cover both sides of the Mainly undisturbed exotics, or one of native or such as pasture stream. Verge more native vegetation side cleared and introduced land. than 30m. on both sides of other vegetation. stream; some wide corridor of introduced or native vegetation. reduced cover of native vegetation
In Stream Cover (10) (8) (6) (4) (2) Abundant cover. A good cover of Some snags or Only slight cover. No cover, no Frequent snags, snags. logs or boulders present The stream is snags, boulders logs or boulders boulders, with and/or occasional largely cleared, submerged with extensive considerable areas areas of in-stream with occasional or overhanging areas of of in-stream and or snags vegetation. No in-stream, aquatic overhanging overhanging and very little In- undercut banks. vegetation and vegetation vegetation stream vegetation. Site may have overhanging bank. Generally no rock overhanging or concrete lining. vegetation
Bank Erosion and Stability (5) (4) (3) (2) (1) Stable: no erosion/ Only spot erosion localised erosion Significant active Extensive or sedimentation occurring, little evident. A erosion evident almost continuous evident. No undercutting of relatively good especially during erosion. Over 50% undercutting of bank, good vegetation cover. high flows. of banks have banks, usually vegetation cover, No Unstable, excessive some form of gentle bank slopes, usually gentle bank continuous areas of bare erosion: very lower banks slopes, no damage to bank banks, little unstable with little covered with root significant structure or vegetation cover. vegetation cover mat grasses, reeds change to bank vegetation or shrubs structure
Riffles, pools and bends (flowing water only) (5) (4) (3) (2) (1) Wide variety of Good variety of Some variety of Only slight variety of Uniform habitat. habitats. Riffles and habitats - eg: riffles habitat - eg: habitat. All riffle or Straight stream, all pools present of and pools or bends occasional riffle or pool with only slight shallow riffle or varying depths, and pools. bend. Some variation in depth. pool of uniform bends present. Variation in depth variation in depth depth eg: of riffle and pool channelled stream or irrigation channel.
Using the Results Sum the values from the habitat assessment, (using the previous table). Use the total score to interpret the results. Excellent (36-40) Site in natural or virtually natural condition; excellent habitat condition. Good (29-35) Some alteration from natural state; good habitat conditions. Fair (20-28) Significant alterations from the natural state but still offering moderate habitat; stable. Poor (12-19) Significant alterations from the natural state, with reduced habitat value; may have erosion or sedimentation problems. Very Poor (8-11) Very degraded, often with severe erosion or sedimentation problems.
Fig. 1.15 Remnant Riparian Vegetation
Fig. 1.16 Highly Modified Riparian Vegetation
Physio-Chemical Tests A range of physical and chemical tests can be undertaken to assess the quality of the water. The most common of these tests for field activities include; • Dissolved Oxygen • Temperature • pH • Salinity • Turbidity • Flow • Nutrients (Phosphates)
Dissolved Oxygen
Dissolved Oxygen is a measure of the amount of oxygen in the water. It is an essential direct measure of the ability of the waterway to sustain life. If dissolved oxygen levels are too low, aquatic organisms cannot breathe, (through the process of respiration). Alternately, if very high levels of dissolved oxygen levels are measured, it can be a sign of a eutrophic event, (ie: excess nutrients and plant growth), in the waterway.
Oxygen enters the waterway through two main processes: 1. Absorption through the water surface (enhanced by waterfalls and rapids) 2. Photosynthesis of green water plants and algae during the daylight periods
Two processes are also working to remove oxygen from the water. These are identified as: 1. Oxygen escaping through the water surface, (eg; bubbles) 2. Respiration of plants and animals in the waterway, (24hrs/day)
Healthy levels of dissolved oxygen in the water are a result of the balance between the processes introducing oxygen and those removing it.
ANZECC criteria: >80% saturation or 6mg/l
Oxygen Variations Over 24 Hours
120 100 80 60 40
Saturation) 20 0 Dissolved Oxygen (% (% Oxygen Dissolved 5am 6am 7am 8am 9am 1pm 10am 11am 12pm Time of Day (hours)
Temperature
Temperature is a measure of one the physical properties of water body. The temperature of the water affects the level of oxygen that can be dissolved in the water, (like bubbles from boiling water, the warmer the water in the waterway the less oxygen it can hold). Temperature also affects the metabolic rate of organisms living the waterway. As a result of the increased speed of chemical reactions, some plants, algae and other organisms can grow at faster rates in warmer waters. As a result, high temperatures are often a contributing factor in algal blooms or other eutrophic events.
Changes in water temperature are not only a result of changes in air temperature with the days and seasons, but are affected by actions in waterways such as: • Clearing of shading vegetation • Runoff from roadways and other urban environments, (these are generally warmer) • Changes in the turbidity of the water column
ANZECC criteria: No guidelines provided
Well established riparian vegetation results in small temperature changes.
pH pH is a chemical measure of the waters acidity. pH is measured on a scale of 0-14, with 0 being highly acidic and 14 strongly alkaline. Both ends of the pH scale, (ie; very high and very low), are corrosive and harmful to aquatic life.
Human impacts on the pH of a waterway are limited. Industrial runoff, fertiliser runoff and significant organic loads can affect the pH of a waterway. However, the most significant human impact on the pH of a waterway is the result of disturbance to potential and actual acid sulphate soils.
Acid sulphate soils are soils high in sulphides, (mainly iron pyrite), that react with oxygen when exposed or disturbed. The oxidisation reaction generates sulphuric acid in small drains and on the soil surface. Rainfall event can then transport the acid into the waterway, dramatically lowering the pH in the process.
ANZECC criteria: 6.5 - 9.0
Acidity increasing [Neutral] increasing Alkalinity
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14
Estuaries 8.5
Strong acids Streams in catchments with Strong alkalis Alkaline rocks & soils (can be Coastal dune streams higher than 8) and lakes (can be lower than 5) Freshwater 6.5 – 8.5
Salinity
Salinity, (electrical conductivity or Total Dissolved Solids), measures the amount of ions or salts in the water. In its simplest form, salinity defines fresh and salt water. However, as an environmental measure of water quality, the outcome is more specific. Aquatic animals and plants can only tolerate small changes in salinity as the concentration of salts in the water affects the ability of cells to control hydration and chemical exchange. Each organism has a specific and limited range of salinity in which it can survive and thrive.
Changes in salinity in the waterway are most commonly the result of tidal or sea water influences. However a number of other circumstances will affect the salinity of the waterway. These include: • Fertiliser and industrial discharges, (generally increase the salinity) • Removal of vegetation and associated rises in the water table, (generally increase the salinity)
NZECC criteria: <1.5mS/cm2
Low Salinity – Upper Catchment High Salinity – Lower Estuary
Turbidity
Turbidity is the clarity of the water. As turbidity increases, less light can penetrate the water column, reducing the amount of light available to green plants for photosynthesis. Increases in turbidity may be seasonal or associated with rainfall events. These are natural and within the ability of ecosystems to cope. Changes in the turbidity beyond the normal range, (either in severity or duration), will affect ecological systems. Possible affects on ecological systems stem from: • Reduction of light for photosynthesis • Increased water temperatures due to the suspended sediments being heated by the sunlight and warming the water • Smothering of bottom dwelling or anchored plants and organisms • Clogging of gills or feeding apparatus for small organisms, (this is especially true if sediments are contaminated with agricultural chemicals)
Actions that may lead to increased turbidity events include: • Clearing of stabilising vegetation on slopes and waterway banks, leading to erosion events • Modification of the waterway to increase flow rates, resulting in increased bank erosion and less settlement of sediments • Cattle or other disturbance to the waterway bed or base
ANZECC criteria: no more than 10% seasonal variation of mean turbidity
Low Turbidity High Turbidity
Flow
Flow is a measure of the volume and speed of water movement in a waterway. In tidal areas flow is determined by regular tidal cycles. In non-tidal areas the flow rate is affected by the physical structure of the waterway and the amount of inputs to the catchment, (either directly via rainfall or through seepage and movement in the soil). The waterways of the Gold Coast, including Currumbin Creek are classified as ephemeral waterways. That is, they have periods of flow and periods of no-flow or dry creek beds. As a result, flow rates are variable, and the aquatic systems have developed and adapted to these conditions. Problems for the ecology of the waterway arise when the flow rates are artificially impacted.
Most commonly this occurs when drainage works are undertaken. The primary purpose of the stormwater system is to protect property and life in storm or other very high rainfall events. One side effect from some stormwater drainage is an impact on the flow rates of the natural waterways.
ANZECC criteria: No guidelines provided
Creek Flow
Estuary Flow
Nutrients
Nutrients are essential building blocks of life. Commonly investigated nutrients are phosphorous and nitrogen. These elements occur in a variety of forms in aquatic environments, some water soluble, some inert and some gaseous. Many of these forms are difficult to undertake field testing for. As a result, field testing should be limited to examination for soluble forms of the elements as these are simple to extract and most likely to be taken into the nutrient cycle. Of the soluble forms of these nutrients, phosphates are the most accessible and reliable to test in the field.
Elevated nutrient levels can trigger excessive plant and/or algae growth. Excess nutrients are one of the key contributors to the major environmental issues of algal blooms and eutrophication. Other key contributors include sunlight and temperature. If all three factors are high and environmental conditions favourable, algal blooms are likely to occur.
Sources of excess nutrients include: • Fertiliser runoff • Degradation of organic matter in waterways, (including garden waste dumped in drains/gutters) • Inflow of sediments and topsoil • Sediments associated with stormwater runoff • Detergents and some other chemicals
ANZECC criteria: >0.1mg/l total phosphorus (prevention of eutrophication)
A high level of nutrients can lead to excess plant and algal growth.
Using the Guide and Developing Catchment Studies
Links to Qld Curriculum
Studies of Society and Environment (SOSE)
Queensland School Curriculum Councils Studies of Society and Environment, (SOSE), syllabus, (years 1-10), provides a generic and specialised option. Each of these are contain 4strands – • Time continuity and change • Place and space • Culture and identity • Systems, resources and power This study guide has been developed in such a way as to provide an insight or opportunity to address each or any of the core learning areas. However, within the limits of this guide, only a limited number of examples of these links can be included. For this purpose, the guide specifically highlights the links with the board SOSE syllabus level 5 and 6 outcomes for Place and Space, the links with the level 5 outcomes for Time, Continuity and Change for the optional Geography syllabus and the level 5 and 6 outcomes from the Place and Space learning area of the optional Geography syllabus.
Further, these links to the curriculum can be enhanced by the use of existing source book modules. Examples of where the information contained within this guide can link to source book modules include:
• 5.1 A question of balance: Australian environments
• 5.7 Urban ecology: Ecology and economy
• 5.9 Adding value through inquiry: Independent study
• 6.2 Managing the future: Australian environments Science Syllabus
Queensland School Curriculum Council’s contains 5 strands – • Science and Society • Earth and Beyond • Energy and Change • Life and Living • Natural and Processed Materials. The information provided in this study guide links most directly with outcomes identified in the Life and Living Key Learning area. However, there are also linkages that can be made with a number of other syllabus areas.
Further, these links to the curriculum can be enhanced by the use of existing source book modules. Examples of where the information contained within this guide can link to source book modules include:
• 5.3 Consequences of interactions in the environment (Life and Living)
Sample Discussion Points by Theme
Water quality parameters – What influence does temperature have on the amount of dissolved oxygen in the water? What is turbidity and how does it affect water quality? How does the time of the day affect the dissolved oxygen result? What are the major influences affecting the pH result?
Ecological Parameters – Discuss how the presence of a species of water bug can influence the assessment of water quality, (i.e. discuss the idea of indicator species and species sensitivity). Discuss the impact of low pH on animals with exoskeleton in relation to the following chemical equation – + H (acid) + CaCO2 = Ca(Salt) + CO2 + H2O A sensitive organism may not be found in a waterway because the chemical conditions in the waterway are toxic, (eg; low pH to many organisms). Discuss another reason why sensitive creatures may not be found in a waterway when the water chemistry does not directly affect the life process of the organism. (Refer to the typical lifecycle of a water bug attached) Discuss the impact of high turbidity on the aquatic ecology of a waterway.
Planning/Management Parameters – Discuss the mechanisms/processes involved when off stream developments impact on waterways, (examples of litter or sediment may be useful). Discuss the role/influence of stormwater on the water quality of a waterway? Discuss the role/influence of land-use in the upper, middle and/or lower reaches of the catchment.
Sample Catchment Tour Itinerary
Time Location Activity Site Number
9.45am Mt Cougall NP, end of Walk the track to the disused saw mill observing the historical One Currumbin Creek Road, and interpretive signage on the way. Currumbin Valley Observe the waterway at the end of the track, this is an example of pristine aquatic environment.
Undertake a habitat survey at this site and rate the site.
0.5 – 0.75 hours
10.30am Entrance causeway to Undertake habitat survey of environment – note changes in Two Mt Cougall NP (walk exotic vegetation types. from previous stop) Undertake physio-chemical testing at site.
Undertake macro-invertebrate sampling at site.
1-1.5 hours
11.45am Lunch 0.5 hours
12.45pm Weir west of Undertake habitat survey of environment – note changes in Three intersection Bourke exotic vegetation types. Lodge Drive and Currumbin Creek Road Undertake physio-chemical testing at site. at Park 0.75-1.0 hours (Bus to following stop)
1.45pm The Alley, Currumbin Undertake habitat survey of environment – note changes in Four Creek Road exotic vegetation types.
Undertake physio-chemical testing at site.
0.75-1.0 hours
The sites listed above provides a range of land-use and water quality experiences from the waterway.
The recommending test activities are chosen to suit the known water quality conditions at each of the sites.
Activities can be removed or altered to meet the specific curriculum aims of the excursion.
Additional activities would include:
• Photographic and observers logs for each of the sites
• Observation and journaling of changes in land-use throughout the catchment
Site 1 – Mt Cougall National Park
Site 2 – testing at the causeway entrance to Mt Cougall NP
Site 3 - area of salt and fresh mixing
Site 4 – inside the mouth of Currumbin Creek
Activity/Data Collection Sheets 1. Stream Habitat Record 2. Macro-Invertebrates Data Sheet 3. Physio-Chemical Data Collection
Note: The following sheets have been produced to use directly or as a suggested guide to incorporate into your lessons. All sheets are fully reproducible and may be altered at your convenience.
Stream Habitat Record
Location: Person(s) conducting
Survey/Test
Date of Survey/Test Easting Time of Survey/Test Northing Length of Stream Examined
Stream Habitat Rating Circle your stream’s rating for each factor in the table below Rating Bank Verge In Stream Bank Erosion Riffles, pools Vegetation Vegetation Cover and Stability and bends Excellent (10) (10) (10) (5) (5) Good (8) (8) (8) (4) (4) Fair (6) (6) (6) (3) (3) Poor (4) (4) (4) (2) (2) Very Poor (2) (2) (2) (1) (1)
Add up all the ratings to calculate a Total Score Total Score:
Rating Score Excellent 36-40 Good 29-35 Fair 20-28 Stream Habitat Rating: Poor 12-19 Very Poor 8-11
Interpreting and Analysing the Results
Excellent Site in natural or virtually natural condition: excellent habitat condition Good Some alteration from natural state: good habitat conditions Fair Significant alterations from the natural state, but still offering moderate habitat; stable. Poor Significant alterations from the natural state, with reduced habitat value; may have erosion or sedimentation problems. Very Poor Very degraded, often with severe erosion or sedimentation problems.
Conclusions from Findings
______
Guide to Vegetation Assessment
Excellent Good Fair Poor Very Poor Bank Vegetation (10) (8) (6) (4) (2) Mainly undisturbed Mainly native Medium cover, mixed Introduced ground Introduced ground native vegetation. No vegetation. little native/ introduced. Or cover, little native cover with lots of bare signs of disturbance or no one under or over-storey, ground, occasional alteration. signs of recent site side cleared, the other predominantly tree. Also includes disturbance undisturbed. introduced vegetation. sites with concrete lined channels.
Verge Vegetation (10) (8) (6) (4) (2) Mainly undisturbed Well-vegetated wide Wide corridor of Very narrow corridor Bare cover or native vegetation on verge corridor. Mainly mixed native and of native or introduced introduced cover such both sides of the undisturbed native exotics, or one side vegetation. as pasture stream. Verge more vegetation on both cleared and other land. than 30m. sides of stream; some wide corridor of native introduced or reduced vegetation. cover of native vegetation
In Stream Cover (10) (8) (6) (4) (2) Abundant cover. A good cover of snags. Some snags or Only slight cover. The No cover, no snags, Frequent snags, logs logs or boulders, with boulders present stream is largely boulders submerged or boulders with considerable areas of and/or occasional cleared, with or overhanging extensive areas of in-stream and areas of in-stream or occasional snags vegetation. No in-stream, aquatic overhanging overhanging and very little In- undercut banks. Site vegetation and vegetation vegetation stream vegetation. may have rock overhanging bank. Generally no or concrete lining. overhanging vegetation
Bank Erosion and Stability (5) (4) (3) (2) (1) Stable: no erosion/ Only spot erosion localised erosion Significant active Extensive or almost sedimentation evident. occurring, little evident. A relatively erosion evident continuos erosion. No undercutting of bank, good vegetation especially during Over 50% of banks undercutting of banks, good vegetation cover, cover. No high flows. Unstable, have some form of usually gentle bank usually gentle bank continuous damage to excessive areas of erosion: very slopes, lower banks slopes, no significant bank structure or bare banks, little unstable with little covered with root mat change to bank vegetation vegetation cover. vegetation cover grasses, reeds or structure shrubs
Riffles, pools and bends (flowing water only) (5) (4) (3) (2) (1) Wide variety of Good variety of Some variety of Only slight variety of Uniform habitat. habitats. Riffles and habitats - eg: riffles and habitat - eg: habitat. All riffle or Straight stream, all pools present of pools or bends and occasional riffle or pool with only slight shallow riffle or pool of varying depths, bends pools. Variation in bend. Some variation variation in depth. uniform depth eg: present. depth of riffle and pool in depth channelled stream or irrigation channel.
Macro-Invertebrate Record Sheet
Macro-invertebrate name/type Sensitivity (1-10) Number
Draw 4 of the Macro-Invertebrates that you found.
Dominant Group 2 Very Very Tolerant Medium Sensitive Tolerant Sensitive Very Degraded – Good- Degraded Poor Medium Tolerant Poor Medium Degraded – Good - Tolerant Poor Poor Good Poor Medium Medium - Medium Poor Poor Medium Good Good
Dominant Group1 Sensitive Medium Medium Good Good Excellent
You Find . . . . . it suggests Little variety of organism types, with large Water overly enriched with selective pollutants numbers of each such as organic matter Only one or two organisms in large Server organic pollution numbers A variety of organisms, but only a few of Stream may have undergone flooding or each or no organisms but the stream scouring appears clean No animals Toxic pollution
Physio-Chemical Record Sheet Mud Map
Conditions
Time
Weather
Chemical/Physical Tests
Water Quality Results Test Result Comments
Dissolved Oxygen mg/L Temperature oC pH pH units Turbidity NTU Salinity (total dissolved solids) µS/cm Flow m3/sec Phosphates mg/L
References and Resources
Books and Publications
CoastalED (2002) It’s all about sand! Educational resource for Gold Coast beaches, CD ROM, Griffith centre for Coastal Management, Gold Coast
D'Agata M., Mc Grath J., (2002), The use of Currumbin Creek as a sand reserve: Towards better dredging management? Proc. Littoral 2002, Porto, Portugal, 22-26 Sep, Vol 2, p495-501
D'Agata, M and Tomlinson, R.B. (2001) Discussion of the Dredging of the Internal Delta of Currumbin Estuary and its Impact on Adjacent Beaches, 15th Aust. Coastal Ocean Engg Conf., Gold Coast, pp. 459 - 463, ISSN 1445-9574.
Gold Coast City Council ( November2002) Health of the Gold Coast Waterways 2002 Report, Gold Coast City Council Catchment Management Unit, Bundall
Gold Coast City Council (1996) Health of the Waterways 1996 Report, Gold Coast City Council Catchment Management Unit, Bundall
Gold Coast City Council (2002) Living City Planning Scheme, Maps and overlays, GCCC Bundall
Licence J (2001) From the Valley to The Alley: a Journey Through Currumbin, GECKO, Currumbin
SEQ Regional Water Quality management Strategy Team (2001) Discover the Waterways of South-East Queensland, Healthy Waterways Partnership, Brisbane
WMB Oceanics (2002) Gold Coast City Catchment Management Study Riparian and Aquatic Vegetation and Fauna Resource Inventory - Volume 1, WMB Oceanics, Gold Coast
WMB Oceanics (2002) Gold Coast City Catchment Management Study Riparian and Aquatic Vegetation and Fauna Resource Inventory - Volume 4 Currumbin Creek, WMB Oceanics, Gold Coast
WMB Oceanics (2002) Gold Coast Waterways, Freshwater Fish and Aquatic Habitats Survey, WMB Oceanics, Gold Coast
Internet Sites
Gold Coast Waterwatch www.goldcoastwaterwatch.org
Gold Coast City Council www.goldcoast.qld.gov.au
Centre for Coastal Management http://www.gu.edu.au/centre/gccm/
Waterwatch Queensland www.qld.waterwatch.org.au
Healthy Waterways www.healthywaterways.org
Waterwatch Victoria www.vic.waterwatch.org.au
Waterwatch South Australia www.sa.waterwatch.org.au/
Waterwatch Australia www.waterwatch.org.au
GECKO www.gecko.org.au
Australian and New Zealand Guidelines for Fresh and Marine Water http://www.ea.gov.au/water/quality/nwgms/volume1.html
Glossary
Barrage A small instream structure designed to limit and modify water flow, generally for the purpose of capturing water for future use Carnivore A flesh-eating animal Catchment A catchment is an area or basin of land bounded by natural high features such as hills or mountains from which all run-off water flows to a low point like a stream, river or the sea Catchment – Lower The area of the catchment where the water exits the catchment – the Lower Catchment refers to least distance upstream from outfall point Catchment – Upper The area of the catchment in the hills and foot hills – the Upper Catchment refers to most distance upstream from outfall point Detritivore Organisms that feed on waste and other organic debris formed by the decomposition of plants and animals Dissolved Oxygen The amount of oxygen dissolved in the water. It is essential for respiration of living creatures Ephemeral Changing, flows for a period and then is dry for a period Estuary The area where ocean and river processes meet and mix – exact definitions are highly variable and technical Eutrophic Having waters rich in nutrients that promote a proliferation of plant life, especially algae, which reduces the dissolved oxygen content and often causes the extinction of other organisms Herbivore An animal that feeds chiefly on plants Macro-invertebrates Macro – visual to the naked eye PLUS Invertebrates – creatures without an internal backbone Nutrient The essential components to growth and life Omnivore An animal that feeds on both animal and vegetable substances pH Chemical property of the water (or soil) describing its acidity or alkalinity Photosynthesis Biological process whereby green plants use sunlight as an energy source to convert CO2 into sugars (energy) and oxygen
6CO2 + 12H2O + sunlight = C6H12O6 + 6H2O + 6O2 carbon dioxide + water + sunlight = glucose + water + oxygen Respiration Biological process describing breathing – respiration uses oxygen and generates carbon dioxide. Plants and animals respire 24hrs a day Riffles Shallow areas in waterways where rocks, pebbles, cobbles or boulders disrupt the surface flow of water – smaller than rapids Riparian The vegetation on the side of the waterway, generally considered to be up to 30m on each side of the waterway. Salinity Refers to the level of salt in the waterway – ocean water has high salinity, drinking water has low salinity Stormwater The waters collected through a drainage system (either piped or open) with purpose of moving built up waters away from infrastructure and housing quickly Turbidity The measure of the waters cloudiness or ability to allow light to pass Urban Areas of residential, commercial development – built up areas Verge Vegetation The vegetation on the direct bank-side or other in-stream structures Weir A small in stream structure designed to limit and modify water flow, generally for separating saline and fresh waters
Maps
Planning Scheme Maps PS-1 Land Use Themes PS-2 River Catchments and Landforms OM-11 Natural Wetland and Waterway Areas Overlay OM-14 Acid Sulphate Soil Hazard Areas
Topographical Maps of Interest 9541 Murwillumbah 1:100,000 9541-1 Burleigh 1:50,000 9541-12 Currumbin 1:25,000 (image map)