The hydro-ecological impacts of reducing the low-flow components of riverine flow regimes have been demonstrated worldwide. While long-term monitoring programs have the ability to assess trend or change in condition, they are insufficient to determine the effects of intervention activities such as the introduction of low-flow restoration measures. Despite modelled evidence that the restoration of low flows will have a positive effect on the receiving environment, there have been few, if any, opportunities to empirically test these responses.
Responses to restoration of low-flows are likely to manifest at multiple spatial and temporal scales, which are important to different stakeholders. Short term, local scale responses are of particular interest to individual landowners while broader-scale responses are the target of restoration programs. The design of a monitoring program must therefore include a suite of indicators capable of detecting short to long-term, fine to broad scales of response.
The current monitoring and research program has been developed to assess the hydro-ecological response to the return of low flow through across multiple catchments using a Multiple Before-After Control-Impact design (MBACI). Short term indicators, such as wetted area, water quality and macroinvertebrates, have been selected to attempt to characterise the short-term response, while longer term indicators, such as fish and vegetation, will utilise existing condition monitoring programs, to monitor the effects in the longer term. The use of a MBACI design will provide a means to detect responses irrespective of natural variation and provide robust and defensible answers to inform the ongoing restoration of low-flows both in South Australia and worldwide.