Townsville Ring Road (Douglas section). Review of environmental factors flora, fauna and water quality

[Extract] The Queensland Department of Main Roads (QDMR)has proposed to implement the Douglas arterial section of the Townsville Ring Road. This includes: °the realignment and upgrade of University Drive leading towards the new Hospital site between CSIRO Davies Laboratory and James Cook University, including the construction of exit and entry ramps; °realignment and upgrade of some of the existing Angus Smith Drive where University Drive will merge to it,; °road construction approximately parallel with the unsealed section of Angus Smith Drive leading from the University entrance towards the Townsville City Council Water Treatment Plant, °major bridge construction over the Ross River, including the construction of exit and entry ramps, and road realignment and widening of Upper Ross River Road. The arterial road (refer to Maunsell McIntyre Pty. Ltd. aerial photo mosaic) will serve initially as an access route to south-western Townsville from the Upper Ross and eventually as a Townsville by-pass route via Hervey's Range Road. In order to meet the requirements of the Review of Environmental Factors(REF) it is vital to identify, describe and assess the environmental advantages, disadvantages and constraints associated with the proposed route. To provide the basis for this assessment, the Australian Centre for Tropical Freshwater Research (ACTFR) was commissioned by Maunsell McIntyre Pty. Ltd. to assess the environmental values of the site with regard to potential impacts of the proposal. An ACTFR aquatic chemist and ecologist conducted a field survey of the site on June 22, 1999. During this site visit, the proposed route was traversed and an assessment of the site made to document and evaluate the structure and floristic composition of the vegetation, provide an assessment of significance of habitats for fauna and determine the environmental value of water courses crossed by the proposed route. This report forms the basis of the REF for issues pertaining to flora, fauna and water quality. A REF is intended solely to provide a preliminary assessment of the possible environmental effects of a proposed project to enable a decision to be made as to whether further and more detailed particulars are required prior to commencement of works

Turbid flow through a tropical reservoir (Lake Dalrymple, Queensland, Australia): responses to a summer storm event

The first flood event following a prolonged dry period is described for an impoundment, Lake Dalrymple, in tropical north-eastern Australia. The event, in January 1996, generated substantial flow in the two main inflow sources: the Burdekin River from the north and the Suttor River from the south. Flow through the Burdekin River peaked early and then subsided to a lower level, but flow through the Suttor River persisted at a moderate level for over 15 days after the initial inflow. An extensive water quality survey was conducted on 16 January 1996 (seven days after the initial dam overflow) to determine the nature of the inflows originating from the two major subcatchments feeding the reservoir as they entered and passed through the impoundment. The inflow comprising waters of high turbidity and low conductivity occupied the mid-column region along the two major inflow channels through the impoundment to the dam wall. The suspended particulate material in the form of silt and clay sized particles remained in suspension as the flow passed through the reservoir, due in part to the low ionic strength of the inflow and the relative densities of the inflowing and receiving waters. For both river sources, more than 50% of the total nitrogen and almost all of the total phosphorus were bound to the suspended particulate matter. Much of this was exported in the flow over the spillway. The highly turbid nature of the inflow resulted in strong attenuation of down-welling photosynthetically active radiation (up to maximum attenuation values of 12.24 m–1 in the reservoir where the euphotic depth was only 0.38 m). The irradiance reflectance and the scattering coefficient were considerably higher than any reported for other Australian inland waters. Concentrations of viable chlorophyll a in the surface waters were very low (maximum value 3.4 μg L–1) because of the highly turbid conditions and extensive dilution by the inflow. The results of this study provide an example of the significant impact a large inflow of turbid, low conductance water can have on a large reservoir in the arid tropics following a prolonged dry period. During inflow events such as the one described in this paper, the reservoir becomes riverine in nature, and large amounts of suspended particulate matter and associated nutrients are transported through the reservoir

Townsville Ring Road (Douglas section). Review of environmental factors flora, fauna and water quality

[Extract] The Queensland Department of Main Roads (QDMR)has proposed to implement the Douglas arterial section of the Townsville Ring Road. This includes: °the realignment and upgrade of University Drive leading towards the new Hospital site between CSIRO Davies Laboratory and James Cook University, including the construction of exit and entry ramps; °realignment and upgrade of some of the existing Angus Smith Drive where University Drive will merge to it,; °road construction approximately parallel with the unsealed section of Angus Smith Drive leading from the University entrance towards the Townsville City Council Water Treatment Plant, °major bridge construction over the Ross River, including the construction of exit and entry ramps, and road realignment and widening of Upper Ross River Road. The arterial road (refer to Maunsell McIntyre Pty. Ltd. aerial photo mosaic) will serve initially as an access route to south-western Townsville from the Upper Ross and eventually as a Townsville by-pass route via Hervey's Range Road. In order to meet the requirements of the Review of Environmental Factors(REF) it is vital to identify, describe and assess the environmental advantages, disadvantages and constraints associated with the proposed route. To provide the basis for this assessment, the Australian Centre for Tropical Freshwater Research (ACTFR) was commissioned by Maunsell McIntyre Pty. Ltd. to assess the environmental values of the site with regard to potential impacts of the proposal. An ACTFR aquatic chemist and ecologist conducted a field survey of the site on June 22, 1999. During this site visit, the proposed route was traversed and an assessment of the site made to document and evaluate the structure and floristic composition of the vegetation, provide an assessment of significance of habitats for fauna and determine the environmental value of water courses crossed by the proposed route. This report forms the basis of the REF for issues pertaining to flora, fauna and water quality. A REF is intended solely to provide a preliminary assessment of the possible environmental effects of a proposed project to enable a decision to be made as to whether further and more detailed particulars are required prior to commencement of works

Sediment dynamics of a large tropical river system: the Burdekin River and Lake Dalrymple, Australia

The Burdekin River Catchment is situated in the dry tropics region of Northern Queensland, Australia and covers 130,000km2. As the second largest catchment in the state it impacts significantly upon the Great Barrier Reef shelf system in terms of water, sediment and nutrient exports, but due to the seasonal nature of rainfall in the region, these impacts are highly episodic. In 1989, the Burdekin Falls Dam was built in order to provide a storage reservoir for irrigation. It was expected to act as a sediment trap, however the reservoir fills and overflows during flood events, which carry large amounts of suspended particulate matter. The reservoir is chronically turbid (>100NTU) and consequently discharge from the dam is no longer clear during the dry season, which may potentially cause adverse affects downstream.\ud \ud Our investigation into the characteristics, source and fate of sediment in the Upper Burdekin catchment and its behaviour within the system has been undertaken within the two major inflowing rivers (Suttor and Burdekin Rivers) and impoundment area during baseflow and stormflow periods. Preliminary results indicate that the high turbidity relates to fine clay minerals of generally <10μm (kaolinite, smectite, muscovite), while sediment deposition within the reservoir has been minimal. A bi-modal distribution implies a second grainsize population related to an organic component. Benthic sediment exhibits a uni-modal distribution and as expected is coarser grained than suspended sediment. XRD work has shown that the composition of the suspended sediment in the inflowing rivers is similar and representative of catchment geology. Suspended sediment grainsize patterns from samples collected post-wet season in the Suttor river and reservoir are virtually identical, which along with turbidity and conductivity data implies that the persistent turbidity in the dam is largely controlled by inflow from the Suttor River

Ecosystem-based assessment and management of marine and estuarine systems at the Queensland Nickel Yabulu Refinery, Townsville

Queensland Nickel Pty Ltd (QNPL) operate the Yabulu Refinery, located on a 2464 hectare land holding on the\ud north Queensland tropical coast adjacent to Halifax Bay, approximately 30 km north west of Townsville. The\ud coastal fringe separating the refinery area from the bay consists of mangrove areas, marshes and sand dunes. Since 1975, excess wastewaters from the refinery have been intermittently discharged via an ocean outfall pipeline extending 1.8 km into Halifax Bay. Since 1997, QNPL have completed a comprehensive Environmental Assessment and Management (EA&M) Program which includes the monitoring of the health of several aquatic ecosystems by considering both ecological and physio-chemical indicators of environmental quality. In undertaking the program, QNPL aim to achieve best management practice by understanding the\ud impacts of the Yabulu refinery on its local environment and managing the environmental impacts appropriately. Results of the EA&M Program to date have identified impacts to Halifax Bay due to the ocean discharge of wastewaters and impacts to estuary ecosystems due to changes in hydrology. Monitoring of ecosystem health in Halifax Bay has found that despite ocean discharge practices, no appreciable impact on ecosystem health measures can be determined nor are elevated levels of contaminants found in fauna tissue samples of biota encrusted around the discharge pylon. Monitoring of estuaries within the coastal fringe did, however, identify that ecosystem health had been affected by refinery activities. The monitoring results indicated that impacts were due to changes in hydrologic conditions such as channel morphology. Remedial works to minimise and\ud remove hydrologic changes are addressing these impacts. This paper describes the EA&M Program and its incorporation into both the strategic and day-to-day environmental planning and management of the refinery operations. In doing so, the paper will discuss how QNPL plan to manage their operations using information gathered from the annual ecological assessment program, environmental assessment programs and stakeholder input

Identifying the land-based sources of suspended sediments, nutrients and pesticides discharged to the Great Barrier Reef from the Tully–Murray Basin, Queensland, Australia

To assist in the development of the Tully Water Quality Improvement Plan, a subcatchment water quality monitoring program was undertaken to identify the pollutants of concern and their land-based sources. Monitoring of suspended sediments, nutrients and pesticides in subcatchment waterways was conducted during the 2005–06 and 2006–07 wet seasons, which both had above average annual flows.We found distinct water quality signals from the basin’s major land uses (forest, grazing, urban, sugarcane and banana cultivation), except for suspended sediment concentrations, which were low across all land uses when compared with neighbouring river catchments. This reflects the high ground cover of the basin and the location of intensive agriculture on low sloping areas of the floodplain, minimising the potential for erosion. Nitrate concentrations were elevated in streams draining sugarcane, indicating fertiliser export from intensive agricultural landscapes. Residues of the herbicides diuron and atrazine were detected at sites draining sugarcane, and on occasion exceeded national ecological protection trigger values, which highlights a potential threat to downstream wetlands of recognised national significance. Herbicides were also detectable offshore in flood plumes of the Tully–Murray Rivers, with some concentrations of diuron above lowest observable effect concentrations for specific species of seagrass and corals. Run-off of nitrate and diuron were identified as key water quality issues in the Tully–Murray basin