Event Monitoring across catchment utilizing community volunteers
to identify major contribution catchments and to validate
Sednet.
Summary: Increased sediment and nutrient
inputs from terrestrial runoff are major threats to the Great
Barrier Reef (GBR) lagoon. The Burdekin River is the largest source
of sediment and nutrient discharge into the GBR lagoon, with an
estimated average delivery of 3.77 million tonnes of fine sediment
each year.
The community-assisted water quality
monitoring project was established in 2003 for the Burdekin Dry
Tropics Natural Resource Management (BDTNRM) body to investigate
suspended sediment (SS) and nutrient concentrations in waterways
throughout the Burdekin Dry Tropics region. The catchment's large
size (133 510 square km), steep upper catchments and dry tropical
environment exacerbated by widespread grazing all combine to form a
system that is highly efficient in transporting freshwater runoff
and associated SS and nutrients off the landscape into downstream
environments, including wetlands and the Great Barrier Reef lagoon.
The project targets wet season rainfall flow events, which comprise
approximately 80% of the annual discharge from the Burdekin River .
Due to the irregular nature of event sampling, it was necessary to
develop a network of landholder volunteers for sampling, especially
where sampling sites were easily accessible from homesteads on
pastorally leased land. During these flow events community
volunteers collect grab samples from subcatchment waterways to
capture changes in SS and nutrient concentrations over the flow
hydrograph. This project has successfully collected samples from
the major subcatchments in the Burdekin region (Belyando, Suttor,
Bowen, Upper Burdekin and Cape catchments) over the 2002/03,
2003/04, 2004/05 and 2005/06 wet seasons. In the most recent wet
season over 30 sites were sampled, including newly established
sites in the 'East Burdekin' region that flow into the Burdekin
River both above and below the Burdekin Falls Dam (BFD). Suspended
sediment samples were also collected from the BFD outlet during a
30 day overflow period.
This data will be a baseline to examine trends in delivery over
time, to validate modelling such as the sediment and nutrient
transports models (SedNet) and to benchmark information for the
Coastal Catchments Initiative (CCI) and for the development of the
Water Quality Improvement Plan.
Project Objectives:
• Quantify
pollutants discharging to downstream aquatic environments
• Identify relative contributions from subcatchments and
land uses
• Increase awareness and ownership of regional water
quality issues within the community
• Ensure scientific design and integrity
• Validate catchment modeling (e.g. SedNet)
Reports:
2005/06 Wet Season Sampling Work Plan (pdf: 455kb)
Bainbridge Z., Brodie J., Lewis S., Duncan I.,
Post D., Faithful J. & Furnas M., 2006. Event based Water
Quality Monitoring in the Burdekin Dry Tropics Region - 2004-2005
Wet Season (5.5MB). ACTFR Report No. 06/01,. Australian
Centre for Tropical Freshwater Research, James Cook University,
Townsville., 89pp.
Bainbridge, Z., Lewis, S., Brodie, J.,
Faithful, J., Maughan, M., Post, D., O'Reagain, P., Bartley, R.,
Ross, S., Schaffelke, B., McShane, T. and Baynes, L. 2006.
Monitoring of sediments and nutrients in the
Burdekin Dry Tropics Region: 2005/06 wet season
(5MB). ACTFR Report No. 06/13 for the Burdekin Dry
Tropics NRM. Australian Centre for Tropical Freshwater Research,
James Cook University , Townsville. 105pp.