Rehydration of catchment landscapes is a well understood mechanism for improving resilience of agricultural systems against climatic extremes and enhancing the landscape’s ecological condition. Moderating the impact of surface water flows during high rainfall events and maintaining water in the landscape during dry times greatly enhances resilience for ecological systems particularly in the alluvial and riparian zones.
Rehydration aims to restore hydrological balance and the natural flow of water in degraded catchments by slowing stream flow, raising overall stream height, and enhancing groundwater-stream interactions. Practices deployed for landscape rehydration include the physical installation of leaky weirs, embankments and rock banks, contour banks, and the revegetation of riparian zones. There is a considerable body of scientific evidence to supports the efficacy of these practices. However, the benefits vary, depending on the catchment antecedent conditions.
The challenge is to know where best to undertake these catchment scale rehydration practices. Evaluating baseline conditions to assess the potential efficacy of conducting rehydration practices is critical in being able to evaluate the merits of investing the required resources.
In collaboration with The Mulloon Institute and supported by NSW DPI, HydroTerra is developing a Catchment Rehydration Selection Tool, akin to a ‘heat map’, a model designed to rank catchments across NSW on their potential suitability for deployment of landscape rehydration practices. The heat map is targeted to provide high-level assessment and guidance for government, industry and private organisations seeking to prioritise the allocation of resources for facilitation of practice-change towards adoption of landscape rehydration.
This presentation will discuss the importance of restoring natural hydrological processes in catchment waterways and landscapes, and the spatial data layers used to assess and ultimately rank catchments according to the potential benefits of implementing catchment rehydration practices.