Whilst the ecological impacts of dams are well known, such as changes to thermal regimes and reduced diversity of macroinvertebrate assemblages, there have been fewer studies of the ecological impact of water extraction on rivers where flows have not been modified by dams. Irrigation extraction during low flows in summer is likely to have similar ecological impacts to drought including reduced habitat and increased water temperature causing changes to macroinvertebrate assemblages. Several studies have examined the potential for pools in inland and intermittent river systems to provide refuge during drought and low flow conditions, but few studies have examined pools in coastal rivers. This study investigates the impact of extraction during summer low flows on water temperature and macroinvertebrate assemblages in two rivers on the far south coast of NSW that have high water demand and high in-stream conservation value. Macroinvertebrates will be sampled quantitatively in 6 refuge pools and upstream riffles in test and control sites. Sampling will be bi-monthly for a 12 month period to determine the ecological impact of pool draw-down from water extraction, whether pools serve as refuges for rheophilic invertebrates, and determine potential recovery rates. Water temperature, dissolved oxygen and pool size will be measured continuously to investigate the relationship between these variables and macroinvertebrate assemblages during pool draw-down. The results of this study will be used to inform Water Sharing Plans which set rules for water use during very low flows.