1.4 Catchment management and water quality Context A catchment is an area of land, bound by hills or mountains from which all runoff water flows to the same low point, which could be a lake, dam, river, creek, bay, wetland or estuary where it enters the sea. Catchments are connected from top to bottom, so what happens upstream in a catchment has a large influence further down the catchment. This is why it is important to manage a catchment as a whole, rather than in parts. One of the greatest threats to marine environments is from land use and development in the catchment. Agricultural use and the progressive urbanisation of land and removal of vegetation leads to substantial changes in both the quality and quantity of water discharged from a catchment. Agricultural and urban runoff contains large amounts of accumulated pollutants, including nitrogen, phosphorus, suspended solids, organic particles and heavy metals. Catchments also include stormwater and wastewater infrastructure which often terminate in the ocean or bays. The quality of water draining from these outfalls can have a detrimental impact on the health of estuarine and marine environments. The State Environmental Protection Policy SEPP (Waters of Victoria) applies to all surface waters of Victoria and aims to provide a co-ordinated approach for the protection and, where necessary, rehabilitation of the health of Victoria's water environments. Specific schedules to SEPP (Waters of Victoria) deal with individual catchments and have more detailed requirements that apply within the catchments. Better land management within catchments is essential for the survival of habitats and the flora and fauna that live within them. Each of the five catchments that border the Victorian coast has a Regional Catchment Strategy, prepared by a Catchment Management Authority. These strategies demonstrate the connections between land, water, and biodiversity with human and natural activities that occur there. Regional Catchment Strategies outline what needs to be done to plan, manage, conserve and use the natural assets in a sustainable and integrated way. The Victorian River Health Strategy and regional river health strategies also contain actions to reduce impacts on downstream environments. Policy 1. Improve integration and collaboration between catchment, coastal, and marine management and programs to reduce the impact of catchment-based land use and activity on the coast. 2. Reduce the impact of effluent and stormwater discharge on marine and estuarine environments by effective treatment and reuse, and water conservation approaches to minimise volumes. 3. Improve and upgrade all ocean outfalls and where possible achieve best practice environmental water management by relocating to a non-sea or ocean disposal area for recycling and re-use. 4. Complete and implement stormwater management plans, prioritising those actions which address source control and are consistent with water sensitive urban design principles. Actions a Establish a marine, estuarine and coastal technical reference group to review regional catchment strategies, propose actions, develop and assess funding priorities and provide coastal, estuarine and marine expertise to catchment management authorities, as required (CMA). b Consolidate and integrate frameworks and programs to address land based sources of marine pollution to the bays, Gippsland Lakes, and other priority areas (CMA, RCB, EPA, LG). c Establish and coordinate a working group of relevant agencies to assess water quality impacts by septic tanks in non-sewered areas in coastal communities (VCC, EPA, LG, VWA). d Promote the need for major land use and operational changes in farming practices to reduce the impact of catchment discharges that impact on the health of marine ecosystems (CMA, DPI, DSE, LG).

10 December 2008