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WELCOME
Richmond Floodplain News
A newsletter about natural resource management on the Richmond Floodplain
Issue 14
In this Issue
NEWS FLOW
A new $320,000 research project aims to better understand the formation of ‘dead zones’ in the Rich-mond River.
Lessons learned in the Rich-mond estuary featured at a global environment confer-ence in London earlier this year.
PROJECT UPDATESReport summarises blackwater
remediation options.
CONTACTS Who’s Who on the Richmond
Floodplain.
Welcome to the Richmond Floodplain Newsletter, an initiative of the Richmond River County Council.
So, we find ourselves at the end of another year.
Reflecting what has happened, it would seem that wet times lead to dry times and we experience the roller-coaster effect on what can be achieved across the flood-plain and estuary.
Over the past 12 months major works have been undertaken to repair the damaged section of the Lismore levee, behind the former Lismore Club.
Restoration works at Swan Bay, which covers 54 hectares, are a stand-out effort.
Apart from the on-ground works, the sustainable long-term man-agement of the Richmond River estuary is now guided by the Richmond River estuary Coastal Zone Management Plan, which was gazetted in February 2012.
Estuary is under the microscope
The challenges facing the Rich-mond River estuary are under the microscope like never before.
Several research projects are look-ing for solutions to some of the major problems facing the estuary.
Richmond River County Council (RRCC) recently contracted envi-ronmental consultant GHD Pty Ltd to carry out a cost-benefit analysis of options for managing the Rich-mond River ‘backswamps’, which form an important part of the river’s floodplain.
The swamps and other low-lying areas, in the Tuckean, Rocky Mouth Creek and Bungawalbin Creek sys-tems, are the source of deoxygen-ated ‘blackwater’, which is responsi-ble for fish kills and other ecological damage.
The GHD report is due to be re-leased soon.
RRCC, Ballina Shire Council and Southern Cross University (SCU) have launched a $320,000 three-year research project aimed at find-ing better ways to manage water quality in the river (see Page 2).
SCU Geoscience co-director and project leader Professor Leigh Sullivan said the geochemistry of deoxygenation events in the Rich-mond River was poorly understood despite regular major floods in the Northern Rivers region.
RRCC floodplain services manager Michael Wood said that with in-kind contributions from the RRCC and Ballina council, the value of the project was about $1 million.
Mr Wood said all the research projects were looking at what was possible to address the problems
Continued, next page.
Blackwater at East Wardell during the January 2008 flood.
The Richmond Floodplain Newsletter – Issue 14 October, 20122
N e w s f l o w
facing the river, which was under increasing stress.
RRCC staff, SCU staff and students and Department of Primary Indus-tries (DPI) staff have combined to research blackwater generation and the effect of peat fires on acid-sulfate soils, in the Bora-Codrington region.
The research investigates the effects of lengthy flooding on vegetation and soil in critical parts of the Rich-mond River floodplain.
The project, by Southern Cross University (SCU) geoscience stu-dent Brendan Maher, is looking at
the deoxygenating potential of surface vegetation and soil during extended periods of inundation in the Bora-Codrington area.
It aims to build on the results of previous research into deoxygen-ated ‘blackwater’ formation and investigate the geochemical effects of flooding on eight vegetation types and two soil types.
Meanwhile, another SCU academic, Associate Professor Caroline Sul-livan, gave a presentation on the lessons learned from research on the floodplain to a global environ-ment conference in London (see next page).
From Page 1
Mullet gasp in deoxygenated water after the January 2008 flood.
of coastal floodplain blackwaters’, the project would investigate the combination of soil, land use and vegetation which created deoxy-genated dead zones.
“We aim to bring this information together into a comprehensive model to allow councils and state agencies to further optimise land-use decisions to help minimise the intensity and duration of deoxygen-ation events in the Richmond River,” Prof Sullivan said.
RRCC floodplain services manager Michael Wood said the project was
the third investigation undertaken by the flood-mitigation author-ity and SCU into flood aggravated impacts on the estuary.
“RRCC actively supports research to assist local and state planning au-thorities with possible management directions for phenomena such as blackwater events, which have major impacts on the Richmond River estuary, particularly following summer flooding,” Mr Wood said.
“RRCC is contributing funds and major in-kind contributions towards the project, including a two-dimensional flood model of the floodplain, the largest of its kind for analysing flood behaviour on the NSW coast.
“Southern Cross Geoscience will use this flood model as an important resource during its investigations.
“RRCC staff also will provide on-ground support to the project through our expertise in floodplain processes, floodplain services and access to land holders.”
A new $320,000 research project aims to better understand the for-mation of ‘dead zones’ in the Rich-mond River.
The areas of deoxygenated ‘black-water’ form during summer floods and have a devastating impact on the estuary when they drain away, often leading to fish kills.
The Richmond River County Council (RRCC) and Southern Cross Univer-sity (SCU) project, which will inves-tigate better ways to manage water quality in the river, is funded under the Australian Research Council’s Linkage Projects scheme.
SCU Geoscience co-director and project leader Professor Leigh Sullivan said the geochemistry of deoxygenation events in the Rich-mond River was poorly understood despite regular major floods in the Northern Rivers region.
“Deoxygenated dead zones are a rapidly growing global crisis in coastal areas,” Prof Sullivan said.
“A major cause of the dead zones in our estuaries is the formation and release of blackwaters from coastal wetlands.
“We will use cutting-edge geochem-ical techniques to get a better un-derstanding of the chemical nature of the compounds being exported into the river as blackwaters during flood events and of the landscape features and management practices that influence the production of these compounds.”
Prof Sullivan said the project team consisted of Associate Professor Andrew Rose, Associate Professor Ed Burton and Professor Richard Bush, all from SCU, and Dr Vanessa Wong, of Monash University.
Entitled ‘Episodic estuarine hy-poxia: Resolving the geochemistry
Research looks at ‘dead zones’
Estuary under the microscope
The Richmond Floodplain Newsletter – Issue 14 October, 2012 3
N e w s f l o w
fluential in decision-making, result-ing in undesirable outcomes, and loss of public benefit.”
They said that in some parts of Australia, market-based instruments had been applied to the conserva-tion of biodiversity, salinity, wind erosion, carbon sequestration, and habitat provision for ground-nesting birds.
Several existing programmes had been applied in the Richmond River, most notably within the Caring for our Country and Landcare initia-tives, but to date, few systematic approaches to management of ecosystem services had evolved.
“As Australia launches into its new Clean Energy Futures policy for emissions reduction, there is now real scope to fund new initiatives to support a payment for ecosystem services programmes,” they said.
“To achieve this however, there is a need for stakeholders to move from privatising the profits from land use while socialising the costs.”
In a conference session abstract they said that by linking specific ecosystem services to clearly iden-tified management actions, they proposed a range of approaches by which land management practices could be improved.
“We present evidence to show how careful management of river basin resources can be promoted, using the quality and extent of selected ecosystem services as a metric,” they said.
“We suggest that the introduction of a framework for the payment of ecosystem services can lay the groundwork by which land holders can be motivated to change their behaviour to support more positive outcomes.”
kilometres), identification and quantification of ecosystem services will provide the basis for the devel-opment of mechanisms to support trade-offs between public benefits and private costs,” they said on the poster.
“This complex process requires the development of sound science, trust between ecosystem service provid-ers (e.g. landholders) and benefi-ciaries (e.g. fisheries, the public), and the development of effective institutions.
“This is a major challenge in the Richmond River, as in addition to private and public land ownership, there are four multi-purpose local councils, three county councils and arguably five state agencies with partial legislative ownership of the river and its environment.
“Land-use decisions by sugarcane farmers, cattle owners, commercial fishers and recreational fishers put conflicting pressure on resources.
“Vested interests are often most in-
The Richmond River featured in one of the sessions at the Planet Under Pressure global environment confer-ence, in London, earlier this year.
Southern Cross University (SCU) Associate Professor Caroline Sullivan gave a presentation on river health and the role of ecosystem services to one of the conference ‘poster sessions’.
Ecosystem services are those services an ecosystem provides to society.
In the case of the Richmond basin, they include water supply, waste re-moval, provision of habitat for fish, birds and other wildlife, provision of agricultural land and industrial land, and provision of sites for recreation and cultural activities.
Prof Sullivan, SCU marine chem-ist Dr Amanda Reichelt-Brushett, CSIRO ecologist Dr James Butler and Richmond River County Council (RRCC) floodplain services man-ager Michael Wood collaborated on a poster, titled ‘Supporting river health: What role for ecosystem services?’, which Prof Sullivan pre-sented at the conference.
They said on the poster that ecosys-tem services underpinned land-scape functionality, and generated many direct benefits and indirect benefits for local people.
Funding to maintain and improve these services could be raised through the federal government’s carbon tax.
Market-based instruments, such as payments for ecosystem services for the protection of floodplains, wet-lands and their associated fisheries, could be promoted through adap-tive co-management initiatives.
“In the Richmond River (6979 square
Richmond River features at global conference
The conference poster.
The Richmond Floodplain Newsletter – Issue 14 October, 20124
P r o j e c t u p d a t eReport summarises remediation options
Continued, next page.
There is a range of options avail-able for tackling fish kills caused by deoxygenated ‘blackwater’ in the Richmond River.
This is the second part of an article which looks at a report chronicling the history of fish kills in the river and presenting the alternatives for prevention and remediation.
In his report on the ‘past, current and future aspects of blackwater fish kills’ in the river, Simon Walsh, the Department of Industry and Investment conservation manager – aquatic habitat rehabilitation, details the history and future of the blackwater fish kills.
Blackwater is produced when micro-organisms feeding on rotting flooded vegetation remove all the dissolved oxygen in the water.
Warm water temperatures associ-ated with summer floods increase the activity of the micro-organisms and the production of blackwater.
This is a summary of Mr Walsh’s as-sessment of blackwater remediation options.
Do nothing
Doing nothing is an option that has immediate benefits – for the short term.
It can be tempting to maintain the status quo as stakeholders know what to expect, upfront costs are negligible and maintenance costs are also low.
However, doing nothing will not address the problem – in this case blackwater production and its as-sociated impacts.
This is the easiest option to imple-ment – by definition it is ‘business as usual’
However, if no remediation is at-
tempted there will be a continua-tion of the significant opportunity costs incurred.
Fish kills will continue with ongoing impacts on fishing industries and associated tourism enterprises and there will be further and potentially worsening social angst between agricultural and fishing industries on the floodplain.
The broader community is unlikely to be satisfied with this response and the threat remains of increasing ecological impacts.
Retain post-flood inundation
This option involves retaining black-water over inundated backswamps after the flood peak has passed.
This would reduce the contribution of remediated floodplains to river-ine deoxygenation.
It could be physically achieved by either filling in the drains or alter-natively, by installing water control structures (where the floodgates are now located) to enable the desired regulation of water into, or out from, the backswamps.
If a greater amount of water was desired to be retained, levees could
be raised at low points using earth-moving equipment.
It is unclear what percentage of in-undated floodplain water would re-quire retention to make a significant difference to blackwater production (i.e. how many backswamps and/or floodplain areas in total).
Further research is also needed to determine the minimum elevation to which water should be ponded in any particular floodplain location and an indication as to how long the water should be held before natural ‘re-oxygenation’ processes are completed.
Management decisions could then be made as to whether it would be better to release this water into the river or to retain it further.
Water retention on this scale is the most promising option now avail-able to physically minimise black-water production and it offers the closest return to ‘natural’ hydrologi-cal conditions – restoring wetland-dependent plant and animal com-munities.
There are multiple ecological ben-efits for improved water quality, fish, water birds, aquatic invertebrates, wetland values, carbon sequestra-tion etc.
Other benefits include groundwater
Deoxygenated blackwater leaves the Richmond RIver at Ballina after the January 2008 flood.
A mud crab, dead fish and prawns at Wardell in January 2008.
The Richmond Floodplain Newsletter – Issue 14 October, 2012 5
P r o j e c t u p d a t eFloodwater retention ‘most promising’
grow a range of wet pasture species that offer improved nutrition and digestibility, particularly for beef cattle production.
Floodgate management
Active floodgate management is the process of controlled opening of floodgates during non-flood peri-ods.
This can be achieved by the instal-lation of one of a variety of engi-neered floodgate modifications that preserve their originally designed flood-mitigation purposes, while al-lowing regulated flushing upstream of the structure.
Flushing results in better water quality parameters – raised dis-solved oxygen and moderated temperature fluctuations.
Laser levelling
This technique has been widely used by the (sugar) cane industry. This involves using earthmoving equipment to create artificially levelled landscapes with a ‘fall’ to
enable a desired drainage flow.
Drain shallowing
Drain shallowing is another tech-nique that has been used by the cane industry. It involves replacing deep, narrow drains with wider, shallow ones.
Alternative land uses/crops
This option involves seeking alter-native uses for the land that are more compatible with being under a wetter management regime.
Some options that could be rel-evant include: Dry-land rice, aquac-ulture, tourism, research and learn-ing opportunities, carbon sinks and indigenous engagement.
Replace pastures
Replanting the floodplain pasture grasses with trees/shrubs is the essential premise of this technique. The trees would need to be planted with sufficient density to inhibit the development of a grassed under-storey.
Careful species selection would be important to ensure that the trees can survive the climatic variations of wetting and drying inherent to floodplain backswamps. Blackwater events have occurred under for-ested vegetation.
The degree of benefit in replac-ing vegetation on the Richmond floodplain would need further as-sessment.
Depending on the particular species selected, the trees could offer other income sources from by-products including nuts, oils, timber etc
More research work is needed to assess the efficacy of some of these options in managing for black-water.
From previous page.
replenishment, sediment/nutri-ent retention, water purification, climate change mitigation and adaptation.
The process would offer significant economic outcomes for industries based on those improved ecologies (including recreational and com-mercial fishing, tourism etc).
However, natural fish kills relating to blackwater would occasionally still occur, although their frequen-cy, duration and severity would be expected to decrease.
Local farmers are innately nervous of suggestions that the ‘govern-ment wants to buy our land and flood it with salt water’.
Raising this suggestion would need to be achieved with some diplo-macy and circumspection.
The exact area and existing land uses of the areas of interest have not been quantified, making an estimate of their purchase value dif-ficult to accurately quantify – how-ever, these are likely to be consider-able and may well fall within the $10 million to $100 million ballpark.
Wet pasture management
This technique involves the pond-ing of freshwater on drained agricultural backswamps during non-flood periods. This assists in raising groundwater levels.
The water level is set within the growing tolerances of wetland species that are palatable to stock (‘wet pasture’), which is generally within 10-15 cm of the local ground surface elevation depending on the farmer’s seasonal management requirements.
By doing this, farmers are able to
Front page of the Northern Star newspaper from January 14, 2008.
The Richmond Floodplain Newsletter – Issue 14 October, 20126
News flowThreat of El Niño recedes
low over the area at this time of year.
Over the rest of the country, the chances of a drier or wetter Novem-ber to January period are roughly equal.
Outlook confidence is related to how consistently the Pacific and Indian oceans affect Australian rainfall.
During November to January, his-tory shows the effect to be mod-erately consistent over parts of western WA, the Kimberley region of WA, most of the NT, Queensland and NSW.
Over northern South Australia, Victoria and Tasmania the effect is weakly consistent, with the remain-der of the country very weakly consistent.
After hovering around El Niño thresholds during winter, tropical Pacific temperatures have retreated to neutral levels over the past sev-eral weeks.
Climate models surveyed by the Bureau of Meteorology suggest sea surface temperatures in the tropi-cal Pacific Ocean are likely to stay at neutral levels during the remainder of 2012 and early 2013.
The national outlook for November 2012 to January 2013 indicates that a wetter than normal season is more likely for large parts of northern and central Australia.
According to the Bureau of Mete-orology, this outlook is mainly a result of warmer than normal waters in the Indian Ocean. Warmer than normal waters in the Pacific Ocean had a lesser impact.
There is a 55 per cent to 60 per cent chance of a wetter than normal sea-son in the Northern Rivers region.
The chances of receiving above me-dian rainfall during the November to January period are above 60 per cent over the Kimberley region in Western Australia, the Northern Ter-ritory and south-west Queensland.
Probabilities exceed 70 per cent over the eastern Kimberley, and parts of the central and western NT.
Such odds mean that for every 10 years with similar ocean patterns to those currently observed, about six years or seven years would be expected to be wetter than average over these areas, while about three years or four years would be drier.
Chances also exceed 60 per cent over south-west WA, but it should be noted that rainfall is commonly
Project aims to raise water tableA new Richmond River County Council (RRCC) project, in the Kookami Swamp, at Bungawalbyn, aims to raise the groundwater table to reduce oxidation of acid-sulfate soils and production of blackwater.
The project, titled ‘Integrated sus-tainable floodplain farming – Rich-mond’, is funded by the Northern Rivers Catchment Management Authority and involves the installa-tion of a rock weir with cleaning and fencing of a drain.
The drain clearing will reduce flood-ing to upstream farmers, enabling agreement for works to proceed.
The weir will be installed and then the drain will be cleaned of veg-etation and attached sediment by working from the upstream end.
Finally, the drain will be fenced to exclude cattle. Excluding cattle will reduce nutrient entry and bank ero-sion while preventing cattle bog-
ging and their subsequent death.
At a later date, the bank can be planted out with trees and shrubs to shade the water and prevent weed growth in the channel, form-ing a sustainable solution.
These project works are in addition to works carried out on the same property by the NSW Department of Primary Industries and Wetland-Care Australia.
Ballina Fishing Co-operativeRegulates the sale of professional fishers’ catch. Contact: Chairman Ballina Fishermen’s Co-operative phone: (02) 6686 2533
Bungawalbyn Catchment Management GroupFormed to source funding, implement on-ground works and demonstrate better management of the Bungawalbyn sub-catchment. Contact: Garry Owers email: [email protected]
Department of Environment, Climate Change and WaterEstuary: Contact: Richard Hagley email: [email protected] Floods: Contact: Toong Chin email: [email protected]
Drain WatchDrain watch groups are being set up by the sugar industry to monitor water quality. This is an outcome of the sugar industry’s three year program develop-ing best management practices for improving water quality in drains. Contact: Rick Beattie, Broadwater Sugar Mill phone: 6620 8200
Environmental Training and Education Inc (ENVITE)Provides training and education to unemployed young people. Engages in environmental works around the catchment. Contact: General manager, ph: 6621 9588 email: [email protected]
Far North Coast WeedsWorks with a wide range of stakeholders to combat the spread of noxious weeds in the Northern Rivers region of NSW.Contact: Jim Willmottphone: 6623 3833email: [email protected]
Floodplain and Acid Sulfate Soils NetworkProvides an avenue for flood mitigation authorities, research bodies, government organisations to exchange ideas and information. Contact: Simon Walsh email: [email protected]
Northern Rivers Catchment Management AuthorityFormed to oversee and identity crucial natural resource and environment management issues for the Northern Rivers and facilitate strategic approach consistent with Ecologically Sustainable Development and Total Catch-ment Management. Contact: John Nagle phone: 6627 0123 email: [email protected]
NSW Department of Industry andInvestment (Agriculture and Fisheries)Agriculture: Soil and water investigations, acid sulfate soil research, best management practices for back-swamps. Contact: Dr Peter Slavich phone: (02) 6626 1200 email: [email protected]
Fisheries: Protect and enhance aquatic habitat in natural waterways within the estuarine reaches of the floodplain. Contact: Simon Walsh phone: 6686 261200 email: [email protected]
NSW Sugar Milling Co-operative, BroadwaterRegulates and processes sugar cane production on the Far North Coast. Contact: Rick Beattie phone: 6620 8200
Pelican Creek Landcare Inc.Riparian restoration and aquatic weed control in the Pelican Creek catchment. phone: (02) 6683 2158
Who’s Who on the Richmond Floodplain
There are many groups involved in the natural resource management in the floodplain. The following is a list designed to help you improve your flood-plain networks. If you know of other groups that should be included, or if any of the details appearing below need updating, please contact: The Gen-eral Manager (02) 6621 8314 or email [email protected].
Who’s Who on the Richmond Floodplain
Richmond Estuary Ecological Health and Management Strategy (REEHMS)
A sub-committee of RFC, coordinating present and upcoming research projects on the floodplain and estuary.
Contact: Dr Peter Slavich email: [email protected]
Richmond River Estuary Management Committee (REMC)
REMC is a subcommittee of RFC, developing a long-term sustainable plan for the estuary from Ballina to Boat Harbour.
Contact: Kyme Lavelle, ph: 6621 8314, email: [email protected]
Richmond River County Council (RRCC)
Responsible for flood mitigation, drain maintenance and water quality in the Ballina, Lismore and Rich-mond Valley areas.
Contact: General manager or floodplain services manager phone: 6621 8314 email: [email protected] or [email protected]
Richmond Floodplain Committee RFC is a committee facilitated by RRCC coordinat-ing natural resource management on the floodplain.
Contact: Floodplain services manager
phone: 6621 8314 email: [email protected]
Richmond River Cane Growers Association
Body representing cane growers on the Richmond River.
Contact: Andrew Ticklephone: 6683 4205
Tuckean Landcare Group
Formed to address chronic land degradation problems within the sub-catchment. Acid sulfate soil is one of the main problems.
Contact: Michael Woodphone: 6621 8314 email: [email protected]
Wetland Care Australia
Concerned with rehabilitation of drained wetlands, and reinstatement of wetlands and their ecological functions.
Contact: Cassie Burns or Adam Goslingphone: 6681 6069 email: [email protected] or [email protected]
Wilson’s River Landcare Group
The main focus of the group is river bank restora-tion and enhancing riparian vegetation at sites along the Wilson River at Lismore.
Contact: Kristin on 6624 7979 or Vanessa on 6624 5500email: [email protected]
Design: Flexible Learning Development Services, Southern Cross University. Editorial: North Coast Media, phone 6683 2295.
Richmond River County Council Floodplain Management website
http://www.rrcc.nsw.gov.au/MORE INFO
