Water quality in undeveloped and pristine areas of the GBR catchment (C2.10)

Task leader: Mr Jon Brodie, James Cook University.

Task associate: Dr David Haynes, Great Barrier Reef Marine PArk Authority.

Increasing discharges of suspended solids (SS), nitrogen (N) and phosphorus (P) to the GBRWHA from the GBR Catchment are recognized as the principal water quality threat to the inshore areas of the WHA. Assessing how changed landuse on the GBR Catchment has altered river loads is essential for setting catchment load targets and prioritising uses and areas of the catchment for management action. This assessment relies on our knowledge of concentrations and loads in waters in ‘pristine’ areas of catchments as well as that present after water has flowed through landuses such as sugarcane, horticulture, beef grazing and urban areas. The differences in these water masses allows us to estimate inputs of SS, N and P from various landuses to rivers draining to the GBR.

ACTFR hold extensive databases of concentrations of SS, nutrients and general water quality parameters for pristine areas of many catchments in north and central Queensland. This data forms part of a large number of individual projects from the last 15 years. This proposal will collate this data (and refer to any other relevant, published data), interpret the data in terms of rainfall patterns, flow regime, geology, soil type, vegetation type and landuse and draw general conclusions as to ‘ambient’ conditions in pristine areas of north and central Queensland catchments.