Urban green spaces impact on the microclimate (moderate temperature), hydrological cycle (increased water infiltration rate and evapotranspiration, slow down runoff), biodiversity (source of habitat for many fauna species), improve water quality and reduce air pollution, remove significant amounts of pollutants such as nitrogen, phosphorus and fine sediments and in general have environmental, social and economic benefits. Adelaide Park Lands, with an area of 720 ha around the City of Adelaide bring environmental, social, cultural and financial benefits for the people of Adelaide. The Adelaide Park Lands provide habitat and green space connectivity for a diverse range of flora and fauna species. Although these green spaces are of great benefit to the community and environment, they require substantial amounts of water to maintain their health and beauty. The use of water for irrigation is often problematic in Australia, particularly in South Australia which is the driest state in Australia. Securing Australia’s water requires a diversity of water sources to ensure the country will be prepared for future water scarcity (droughts) as the population grows. Recycled water is one of the main water resources which can make a substantial contribution to increasing the security of future water supplies. Scientific and technical studies are required to maximize this contribution through developing water recycling opportunities and reuses, particularly for green space irrigation, to provide environmentally, socially and economically sustainable environments. The use of municipal recycled water for green space plants is a valuable attempt to use the easily available water resources but it requires a monitoring system to mitigate the possible adverse impacts on the soil, plants and groundwater. Variables such as climate, weather, irrigation methods and frequency, plant genetic variations and plant species, soil health and soil physical and chemical characteristics can have a profound effect on the sensitivities of plants to salts and various toxic elements. Soil drainage, irrigation application rate, irrigation water quality, rainfall characteristics (volume, intensity and frequency), and plant canopy shade can influence the long-term effects of salinity, and toxic effects of chemical compounds on the vegetation health. It is, therefore, important to have information specific to each individual plant species, as well as information on all the above-variables, specific to each locality, in order to properly plan and manage water requirements of specific landscapes. There is currently a lack of adequate information specific to the Adelaide Park Lands vegetation, their tolerance to salinity and toxicity and their threshold levels. There has been little research to investigate water requirements of mixed vegetation in urban landscapes such as plantings in the parkland systems. In addition, research is required to examine the methods to remove pollutants from the recycled water. This report is part of a larger investigation of the response and sensitivity of landscape plants within the Adelaide Park Lands to the use of Glenelg recycled water for irrigation. The scope of this report includes: a review of the current literature on possible impacts of the use of treated wastewater on native plants in the Adelaide Park Lands, detailing potential toxic effects of salinity, sodium, chloride and boron; an introduction to the major plant species reported in the Adelaide Park Lands as well as their characteristics and functions within the Australian landscape; a summary of water logging, salinity, sodium, chloride and boron tolerance of the selected species (provided in Appendix 2); recommendations for the planting design within the parklands and watering methods and regimes for the same area and also the research gaps that are required to be investigated for a more sustainable use of Glenelg recycled water for Adelaide Park Land irrigation. This study uses plant species found on the lists reported (Long, 2003), with the main focus on plants available in the largest number of parks within the parklands. The major aim was to provide specific information on their botanical characteristics and tolerance to salinity and to certain toxic elements, focussing on sodium, chloride and boron. 6 The annual average salt concentration in the Glenelg recycled wastewater is 1190-1200 mg/l or 1.8dS/m. Although the salinity variation in usual irrigation water is expected to vary up to 3 dS/m, irrigation with Glenelg recycled wastewater with an irrigation application rate of 4.5ML/year-ha would cause annual accumulation of nearly 9 tonne/ha salts to the soil. In the absence of an efficient irrigation management strategy, salinity build up hazard would be problematic in the long term. The average sodium and chloride level in the Glenelg recycled wastewater is 231 and 389 mg/l, respectively. However the sodium and chloride concentration levels in usual irrigation water are expected to be 0-920 and 0-1065 mg/l , respectively. This shows that the sodium and chloride concentration in the Glenelg recycled wastewater is below the maximum allowable level. However, it does not mean that accumulation of these two toxic ions in the long term, without considerable attention to sustainable irrigation management, would not be a hazard for the Adelaide Park Land plants particularly those that are sensitive to toxicity of these elements. The findings suggest that further research would be needed to clarify the benefits of the irrigation of urban green spaces by recycled water and improve irrigation management to mitigate the possible inverse impacts of recycled water for a sustainable environment to ensure having a healthy plant, soil and water system across the Adelaide Park Lands.