The condition of the river is declining

• Long-term monitoring by the Department of Water (DoW) shows that water quality in the middle and upper sections of the Swan Canning river system is in moderate to poor condition and declining. This is due to decades of human impact in the catchment and urban areas, and the more recent changes in climate. Of particular concern is the influx of nutrients and organic matter from urban and rural areas. Nutrients have been recognised as a key threat since the 1990s.
• Our drying climate has meant less water flow into the river system and less nutrient run-off from agricultural areas. However, it has also meant less flushing in the upper rivers so that nutrient concentrations have remained high. More nutrients will flow into the river if rainfall levels increase to those experienced previously.
• The water quality in the lower estuary is in reasonable health but there is evidence that all is not well. Seagrass and prawn populations have declined and salinity and water temperature have increased. The lower estuary is subject to similar pressures as the middle and upper sections but the effects are less obvious due to the larger water body and regular flushing by tidal seawater.
• Experience elsewhere shows that it is possible to improve the health of rivers in urban areas. While many river systems still have to achieve their target health status there are two factors common to their success so far. These are the cooperation of key stakeholders and ensuring a long-term commitment to sustainable funding.

Some improvement strategies are working

• A number of direct actions are in place and proving helpful in combating the decline of the river system. These include:
  • collaboration with local governments and community groups has resulted in the construction of wetlands and drainage nutrient intervention works to remove nutrients and pollutants from stormwater, revegetation of bare drains to become ‘living streams’, and the use of soil ‘amendments’ to help retain phosphorus in the soil. Ideally these pollution sources should be minimised before they enter the drainage network
  • the Trust and DoW operate four oxygenation plants at a cost of $1.5 million per year to reduce the effect of high nutrient levels in the river. These programs help prevent algal blooms and fish deaths.

Capacity to manage threats to the river is hampered

• Efforts in the last 20 years to manage key threats have been less successful. The reasons for this are varied but are closely linked to the dispersed and overlapping authority between state government agencies and LGAs. In most instances the Trust can only influence other agencies and organisations rather than act itself. As shown below, action to combat key sources of nutrients and pollutants has not been effective.

Urban drains are a year-round major source of pollutants from small to medium-sized industry, agriculture and from domestic sources. No single agency is responsible for overseeing Perth’s urban stormwater and drainage system before it enters the river system. Many agencies could influence water quality in their sections of the drainage network, yet no agency is mandated to do so. Once water from local drains enters the river, the Trust and LGAs are left with the difficult task of managing the nutrients and pollutants it carries. Some actions have been taken to reduce these pollutants but these have been insufficient to make any significant difference. Preventing the pollution is generally regarded as more cost effective than treating the polluted river system.

Nutrient flow into the river from rural farms has long been recognised as a major source of pollutants. Efforts to date to reduce these nutrients have been largely unsuccessful. Recent strategies have involved visits by the Department of Agriculture and Food WA to a small number of farms in Ellen Brook to demonstrate to farmers that soil testing can often show that they can significantly reduce their use of phosphorus fertilisers. It can also lead to the use of low soluble phosphorus fertiliser, which is less harmful. But, achieving any meaningful change will require greater effort and may also require additional legislation.

Development  of  new  urban  areas  will  release  significant nutrient  loads  and  other contaminants from the soil and groundwater into the river system unless prevented. The Trust has a role in assessing or providing advice on development proposals and DoW advises on reducing nutrients entering the river system. But, better planning processes would ensure the Trust’s advice is obtained for all developments that will significantly impact the rivers and at the most appropriate stage. As mentioned earlier, it is more cost effective to stop nutrients entering the river system than treating the polluted system.

Gaps in planning and reporting limit action to enhance river health

• There has never been comprehensive and easily understood reporting to Parliament and the public on the overall health status of the river system. DoW developed a draft report card on the health of the river in 2011 that would have provided this level of understanding but it has never been published. Without a good understanding of the condition of the river, necessary actions may not be given the priority they need.
• Seven years after the Act was passed, the Trust’s RPS has not been approved. An approved RPS would establish goals and targets and specific commitments by individual agencies. The RPS is also a framework to monitor, evaluate, and report on the river systems’ health and actions to improve it. We were advised the Minister did not approve the RPS in 2012 due to the imminent State election. It is now on hold pending the amalgamation of the Trust with the Department of Parks and Wildlife.
• The Trust has numerous plans and published reports which comment on threats to the river’s health. The Trust’s current plans typically outline what can be done in the next five years within existing resources. Yet it has not informed Government of what needs to be done to restore the condition of the river and an estimate of what this might cost. Local Water Quality Improvement Plans go some way towards outlining key threats and actions necessary to improve water quality, though actions are not prioritised or costed. An approved RPS would greatly enhance understanding about threats and enhance the capacity of the Trust to focus actions on the highest priority threats.
• DoW’s water quality monitoring is robust and uses similar indicators to that used by other estuarine river managers throughout the world. It is sufficient to determine the status of the estuary and rivers and provide an understanding of the physical, and some biological, functions of the system. More consistent use of biological indicators, smaller-scale monitoring programs and flow gauges would deliver a more comprehensive understanding of the river system.

Recommendations

The Swan River Trust should:

• regularly inform Parliament and the community on the overall health of the river using a comprehensive, and easily understood report
• take necessary action to have the River Protection Strategy adopted
• prioritise key threats to the river’s health and the most effective actions to address these ensure the indicators and monitoring used are sufficient to report to government on the status of the river, to better understand the changes that occur, and to provide effective management of the river system
• work with agencies and Local Government Authorities to clarify responsibility for managing and maintaining water quality in drains, rivers and tributaries throughout the Perth metropolitan area and the Swan Canning river system and identify the additional resources required to enable this to occur
• work with government, agencies, businesses and the community to effectively reduce contaminants in groundwater and stormwater from entering drains and the river system
• review the Fertiliser Action Plan and Fertiliser Partnership to ensure the most effective combination of strategies from both are implemented to prevent nutrients entering the river system
• work with planning entities, developers and other organisations associated with major developments and land use changes to ensure that its advice on how to minimise nutrient discharge into the drainage and river systems is provided when it is most needed
• work with the Department of Planning to improve role clarity in the administration of planning controls outside the Development Control Area
• improve dialogue with the Department of Planning on the requirements and appropriate interpretation of management guidelines to reduce the release of nutrient and other contaminants into the river system by new developments