Managing nutrients to limit coastal algal blooms
- Policy implementation guidelines
- Technical guidelines
- Nutrient hazardous areas
- Criteria for identifying and mapping nutrient hazardous areas
- Hazard maps
The increased occurrence of coastal algal blooms is a worldwide phenomenon linked to nutrient-enrichment of coastal waters. This is also a concern in Queensland where blooms have increased in incidence, duration and intensity (e.g. toxic Lyngbya blooms in Moreton Bay). Such blooms have negative impacts on aquatic communities and pose a significant threat to human health, biodiversity, water quality, marine megafauna, and the recreational and commercial values of coastal waterways.
Nutrients of concern that contribute to increased algal growth include phosphorus, iron, nitrogen and organic matter (dissolved organic carbon). Land-based development and management activities that disturb soils and sediments, or alter the natural hydrological regime (including groundwater levels and composition and surface-water run-off), can mobilise and transport increased loads of nutrients into coastal waters.
The following documents contain specific policy provisions to better manage development and activities that mobilise and transport nutrients of concern to waters where they exacerbate coastal algal blooms:
- South East Queensland Regional Plan 2009-2031;
- Draft Wide Bay Burnett Regional Plan;
- State Planning Policy for Healthy Waters (SPP Healthy Waters).
These policies outline requirements to identify nutrient hazardous areas & ensure urban development in these areas is located, designed, constructed & operated to avoid the mobilisation and release of nutrients of concern for coastal algal blooms.
Policy implementation guidelines
The coastal algal bloom (CAB) implementation guideline Implementing Policies and Plans for Managing Nutrients of Concerns for Coastal Algal Blooms in Queensland (PDF, 2.3M)*, provides direction for State and local governments, industry, consultants, land and natural resource managers and the community on how to implement these policies into planning and development assessment. The document also provides direction for incorporating algal bloom nutrient management initiatives into non-regulatory frameworks and activities.
Coastal algal bloom nutrients of concern technical guidelines (CAB technical guidelines) are currently being developed to provide further support on sampling, assessment and management of nutrients of concern for coastal algal blooms. They will include methods for developing hazard maps, best-practice water and groundwater management for nutrients of concern (particularly iron and organic matter) and model development conditions.
Nutrient hazardous areas
Nutrient hazardous areas are defined in the SPP Healthy Waters as land areas containing appreciable levels of nutrients of concern (particularly nitrogen, phosphorus, iron and organic matter), that may contribute to the increased occurrence, frequency or intensity of coastal algal blooms. In nutrient hazardous areas:
- when planning or undertaking assessable development or high-risk activities under the Sustainable Planning Act 2009 and Environmental Protection Act 1994, specific planning and management measures may be required to prevent or minimise the release of nutrients of concern to waters;
- for non-regulated activities, best-practice management initiatives, targets or actions to address the management of nutrients of concern are encouraged.
See the CAB implementation guideline for further information.
Criteria for identifying and mapping nutrient hazardous areas
Nutrient hazardous areas are restricted to catchments that flow to the Queensland coastline and local government areas listed in Appendix 1 of the CAB implementation guideline. These areas are shown on the following maps:
- Map of Queensland (PDF, 1.4M)* showing geographic limits of nutrient hazardous areas;
- Map of South-East Queensland Coast (PDF, 1.0M)* showing geographic limits of nutrient hazardous areas (A3-508389);
- Map of Gladstone to Gympie (PDF, 888K)* showing geographic limits of nutrient hazardous areas (A3-508382);
- Map of Central Queensland Coast (PDF, 933K)* showing geographic limits of nutrient hazardous areas (A3-508381);
- Map of North Queensland Coast (PDF, 911K)* showing geographic limits of nutrient hazardous areas (A3-508380);
- Map of Northern Cape York (PDF, 759K)* showing geographic limits of nutrient hazardous areas (A3-508379);
- Map of Southern Gulf Area (PDF, 721K)* showing geographic limits of nutrient hazardous areas (A3-508378).
Within these areas, the following criteria are used to identify nutrient hazardous areas:
- Areas identified as ‘very high’ or ‘high’ on detailed-scale hazard maps;
- Where detailed-scale Hazard Maps are not available, areas identified as ‘very high’, ‘high’ or ‘medium high’ on coarse-scale hazard maps; or
- Where both detailed-scale and coarse-scale hazard maps are not available, areas shown as nutrient hazardous areas on a ‘temporary nutrient hazardous area overlay’.
In addition to these mapped areas, nutrient hazardous areas can also include the following:
- Areas that have had activities involving the addition, concentration or generation of appreciable nutrient(s) of concern or where such activities are proposed to begin or intensify (e.g. effluent disposal and wastewater treatment; activities involving organic wastes/manures such as feedlots, poultry, etc; fertiliser inputs such as horticulture, cropping, forestry and golf courses);
- Areas involving activities where substantial disturbance of soil and/or groundwater that may mobilise nutrient(s) of concern are occurring or where such activities are proposed to begin or intensify (e.g. dredging, canals and marinas, tunnels, maritime infrastructure, ports, extractive industries, mining, major pipelines and other major projects including those deemed as ‘state significant’); or
- Areas involving activities generating airborne/volatile particles containing nutrients of concern (e.g. commercial poultry sheds) or where such activities are proposed to begin or intensify.
Hazard maps are decision-support tools for the spatial identification of nutrient hazardous areas. Further information on hazard maps, the different scales and their application is provided in the CAB implementation guideline. The methodology for producing coarse-scale and detailed-scale hazard maps, and developing ‘temporary nutrient hazardous area overlays’, is currently being finalised.
Coarse-scale hazard maps are currently available for the following areas:
Detailed-scale hazard maps (~ 1:50 000 scale) are currently being developed for the following areas:
- Parts of Moreton Bay Regional Council area (southern Bribie Island, Pebble Beach to Deception Bay and Sandstone Point to Glass House Mountain Creek).
* Requires Adobe Reader
Last updated 6 July 2011