Biogeochemical & Ecological Studies

What sets the work CCB does apart from others is the integration of biogeochemical and ecological studies. This delivers our Clients a more comprehensive understanding of their aquatic systems helping them to make better informed decisions to manage their aquatic resources and meet their regulatory requirements.

Lower Richmond River Client: Department of Commerce
We undertook detailed biogeochemical and ecological studies to determine the volume and quality of reclaimed water that can be released into North Creek Canal and the Richmond River Estuary from the proposed West Ballina Reclaimed Water Facility (RWF), under a range of flow conditions, that will cause minimal ecological impact. A complete ecological assessment of North Creek Canal was undertaken including water quality (review of existing data only), sediment contamination, biogeochemical processes, effluent plume tracing and ecological communities to determine the impact of current release volumes. The impact of future reclaimed water volumes and quality from the proposed RWF on water column nutrient and algal biomass concentrations was quantified using a 1-D salt-balance, a box flushing and an empirical chlorophyll-a model. An assessment was also made of the likely impact of the proposed reclaimed water volumes and quality on the ecological health of North Creek Canal and the Richmond River Estuary.
Client Outcomes: This study assessed the impact of discharged wastewater on the ecosystem health of the receiving waters and was instrumental in determining the type of wastewater upgrades required by our clients facilities.

Brunswick River Estuary Biogeochemical and Ecological Study. Client: Byron Shire Council
CCB carried out water quality monitoring and analysis, sediment sampling and analysis, state-of-the-art biogeochemical measurements including benthic nutrient fluxes, sediment denitrification, and benthic productivity and respiration, and macrofauna sampling, over a 5-year period, and constructed conceptual models and nutrient budgets of the system.
Client Outcomes: This study assessed the impact of discharged wastewater on the ecosystem health of the receiving waters and was instrumental in the move by our clients to upgrade wastewater treatment facilities. We also developed 1-D salt-balance models that were used by our client to assess proposed upgraded wastewater discharge scenarios and decreased catchment nutrient exports.

Pimpama River Estuary Ecological Study. Client: SKM for Gold Coast Water
The objective of this study was 'to determine the sustainable quantity of reclaimed water that may be released to the Pimpama River Estuary from the future Pimpama Water reclamation Facility, taking into consideration a wide range of constraints, including, but not necessarily limited to water quality, fisheries values and the ecological health of the estuarine environment'. CCB carried out the biogeochemical components of this study including water quality monitoring and analysis over a 12 month period, sediment sampling and analysis, state-of-the-art biogeochemical measurements including benthic nutrient fluxes, benthic productivity and respiration, sediment denitrification, and sediment N-fixation, and construction of conceptual models and nutrient budgets. Our work contributed the following to the study:

• we developed conceptual models of how the ecosystem functioned based on our biogeochemical measurements. These conceptual models formed the basis of the predictive ecological model of the system. This predictive ecological model was significantly more advanced than any ecological model that had previously been developed in Australia, in part because of the conceptual ideas and biogeochemical measurements provide by us.
• our water quality, sediment and biogeochemical processes data was used to calibrate and verify the predictive ecosystem model.
• we constructed nutrient budgets of the ecosystem to evaluate if the predictive ecological model gave a realistic representation of the system.
• we used our water quality, sediment and biogeochemical processes data, in combination with other ecological data, to assess the current ecosystem health.
• we used our knowledge of how aquatic ecosystems change in response to nutrient loading to assess the likely impact of the proposed wastewater discharge scenarios on the ecosystem health. Traditional ecological data such and macrofauna biomass, abundance and diversity is much more useful as an ecological health indicator when combined with biogeochemical data.

Client Outcome: Overall this project demonstrated that the proposed discharge from our clients new wastewater treatment facility would meet their environmental regulatory requirements. Such a comprehensive project (i.e. traditional environmental and ecological studies and state-of-the-art biogeochemical studies and modelling) was required because the receiving waters are an environmentally sensitive area and environmental compliance could not have been demonstrated with traditional sampling, survey and monitoring programs.

Maguire's Creek Ecological Study. Client: Department of Public Works and Services for Ballina Shire Council.
To evaluate if it was warranted spending millions of dollars to upgrade a wastewater treatment plant our client wanted to know the current impact of discharged wastewater on the ecosystem health of the receiving waters. We undertook this assessment using a combination of traditional environmental and ecological parameters and state-of-the-art ecosystem process measurements. Indicators used in this assessment included maximum and minimum dissolved oxygen concentrations, nutrients and algal biomass, algal species, benthic productivity and respiration, aquatic macroinvertebrates, riparian habitat and vegetation surveys and nutrient budgets.
Client Outcome: This study demonstrated that our client was justified in upgrading wastewater treatment facilities on environmental and ecological considerations.

Emigrant Creek Ecological Study. Client: Department of Public Works and Services for Ballina Shire Council.
As part of our client's urban water management strategy one option was to discharge highly treated wastewater into Emigrant Creek. We were commissioned to evaluate the current ecological health of the system and assess the likely impacts of the proposed wastewater loads on the ecosystem health. We used a combination of traditional environmental and ecological parameters and state-of-the-art ecosystem process measurements. Indicators used in this assessment included maximum and minimum dissolved oxygen concentrations, nutrients and algal biomass, algal species, benthic productivity and respiration, aquatic macroinvertebrates, riparian habitat and vegetation surveys and nutrient budgets.
Client Outcome: This study demonstrated for our client that the discharge of highly treated wastewater into Emigrant Creek was not a suitable option on the basis of environmental and ecological considerations.

Updated: 16 December 2010