Science evaluation of coastal wetland systems repair projects across GBR catchments

Nathan Waltham

Led by: Dr Nathan Waltham, JCU


Project Summary

State and Federal agencies are funding many GBR wetland system repair projects (Mungalla wetlands $1.2M; Reef Trust/Greening Australia $4M; Restoring Burdekin Coastal Ecosystems $837K; Roundhill Creek wetland/FHA $65K, Babinda Swamp Constructed Wetland ~$1.97M). The problem is no scientific data evaluates their success; this project partners with NRMs to fill this R&D gap. Using advanced scientific hydrological and ecological techniques we will generate data to evaluate repair efforts, providing surety to government funding agencies. This project will provide a platform to attract significant private and philanthropic investors, looking to fund large-scale wetland repair projects, via emerging carbon and nutrient trading schemes.


Project Publications
Final Report – Mungalla
Final Report – Babinda
Final Report – Round Hill
Journal Article
Journal Article
Journal Article
Journal Article
Journal Article
Journal Article
Journal Article
Journal Article
Journal Article
News Article
News Article
NQDT Factsheet
Media Release


Project Video


Project Webinar – 17th November 2020


Problem Statements

Problem – coastal wetland degradation

Coastal wetlands adjacent to the Great Barrier Reef (GBR) have incredible environmental, cultural and economic value. Despite this, over 70% of GBR coastal wetlands have been modified, impacted or lost entirely because of continuing land use change (such as agricultural, aquaculture, peri-urban/urban, and industrial expansion). Of the wetlands remaining many now provide severely reduced aquatic and avian habitat, due to alien weed infestation and poor water quality. A large number of coastal wetlands have also lost their connectivity with estuaries that flow into the GBR lagoon (e.g. due to earth bunding), which can impact marine and freshwater aquatic (diadromous) species that have a critical estuary lifecycle phase, and rely on this connectivity between the reef and shallow tidal and freshwater wetlands.

Response – coastal wetland system repair

In order to halt and reverse wetland decline, State and Federal government agencies have responded by investing significant funding in various forms of coastal wetland system repair, mainly coordinated through NRM bodies. In addition to these existing investments there are also large amounts of funding on the horizon, that will be delivered through government and private investments, for example, via nutrient and carbon trading markets (‘blue carbon’). Examples of these new economic levers are being explored through projects in the NESP TWQ hub: 1) Priority 1D; Innovative approaches for using economic levers for achieving nutrient/sediment loss reductions and/or to encourage land use or practice change; 2) Project 2.2, N-trading for sugarcane catchments; and 3) Project 2.1.2 Land transition in low lying, marginal cane land).

The key problem is that there is a lack of scientific data to support and give surety that onground wetland repair investment achieves water quality and biodiversity returns. Most existing and future wetland improvement projects have the objective of reducing invasive aquatic weeds, improving water quality and increasing usable habitat and marine connectivity for aquatic species, however, scientific data evaluating the degree to which this actually happens is not available. This is particularly true for long-term impacts beyond the first few years of remedial management. Scientific data and long term evaluation methods are therefore particularly necessary to track the progress against broader program objectives, in particular those contained in a number of policies and planning documents (e.g., Queensland Government Wetlands Strategy 2013, Reef 2050 Long Term Sustainability Plan, Reef Water Quality Protection Plan 2013, and regional NRM plans and WQIPs).

In preparing this research proposal, we’ve been inundated by project partners nominating wetland repair sites. We interpret this as a sign that scientific data is critically needed. We have taken the approach to focus on sites that represent the range of management scenarios, and across a geographical range (there could have been many more sites nominated). To manage this and ensure end partner adoption of the project, we’ve formed a partner group (Greening Australia, NQDT, Terrain, Queensland Government (Wetlands Team), Lower Burdekin Water) to help the research design, implementation, data interpretation and reporting – these partners will be involved at all key project stages.

How Research Addresses Problem
Reef Trust/Greening Australia are about to spend $4M, Burdekin water/NQDT are about to commission up to $837K, Burnett Mary Regional Group $65K on the Roundhill Creek and Fish Habitat Area connectivity project, and Lower Burdekin Water ~$250K in lower Lilliesmere/Kalamia creek, and Babinda Swamp Constructed Wetland due to be finalised in the next 6mths $1.9M. This project partners with these organisations, to provide direct research support where each currently lack a R&D component. This research project will generate data to explicitly examine the effectiveness of these on-ground investments, provide science based evidence of their success, provide surety in the adoption of on-ground works and enable the identification of similarities and patterns across projects that point to the development of context specific guidelines on wetland system repair.

The strength of this research project is simply stated; it will quantify the biodiversity and water quality improvements/benefits in a number of on-ground projects that are trialing a range of different wetland repair techniques (bund wall removal, aerial weed spraying, mechanical weed harvesting, flow management manipulation). This will generate data in a scientifically consistent way that will allow the pro and cons of each management method to be evaluated (this is very separate to monitoring data which is not proposed here). As the data will be quantitative, the ecological improvements per dollar of investment can also be calculated, thereby highlighting the relative cost effectiveness of the different forms of wetland repair. These data will be useful in continuing to improve our understanding of wetland services, repair efforts and water quality outcomes for downstream marine habitats (which would give guidance on specific guidelines on wetland system repair). This evaluation will provide a basis for future wetland projects, stimulated through private sector interests in (blue) carbon and nutrient trading/offset schemes.

Alignment with NESP Research Priorities
3b) Evaluate existing or future management solutions for coastal freshwater wetland system repair (incl. artificial wetlands and improved irrigation management where this benefits existing natural wetlands). Must examine these management solutions via linkage to existing projects/programmes and must address water quality benefits and/or connectivity with marine habitats.


Project Keywords

Water quality; Wetland system repair; Biodiversity; Ecohydrology; Indigenous engagement.


Project Funding

This project is jointly funded through JCU, GU, CSIRO, Mungalla Aboriginal Business Corporation, NQ Dry Tropics (NRM), Terrain (NRM), Burnett Mary Regional Group (NRM), QDEHP (Wetlands), Lower Burdekin Water, Greening Australia, Jaragun Natural Resources Management, GBRMPA and the Australian Government’s National Environmental Science Programme.


Project Map

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Markers are not an exact position of where the research is taking place, they are only to be used as a guide to the general area in which it is being carried out.