To support sustainable river management, since 1994 the Tasmanian State Government has conducted broad-scale monitoring of river condition in Tasmania under the River Health Monitoring Program (RHMP). The RHMP employs Australian River Assessment System (AusRivAS) protocols, which focus on macroinvertebrate communities and habitat quality. Since the RHMP began, land and water use has changed markedly and river health science has advanced. Because of this, a review of information collected by the RHMP between 1994 and 2016 was undertaken. The review of the program: (1) documented its history; (2) assessed applications of resulting data and the applicability of other measures of river condition; (3) evaluated the value of its abiotic and biotic data; (4) examined spatio-temporal patterns in macroinvertebrate communities and river condition; and (5) revised its purpose and design.
To date, outputs from the RHMP have been used for a wide range of purposes relating to the management of water and natural resources at varying spatial and temporal scales (e.g. detecting point-source pollution effects, national State of Environment reporting). However, the current design of the RHMP was found to have several limitations, particularly as its sampling regime focuses on a single bioindicator (aquatic macroinvertebrates), and the accuracy of several habitat measurements is low. Despite these issues, macroinvertebrate data from the program suggest temporal and spatial declines in river condition in several areas of Tasmania since 1994. Currently, the reasons for these declines are unclear.
To improve the overall value of the RHMP, the breadth of monitored parameters and the rigor of the methods that are used to monitor some parameters will be increased. In particular, quantitative measures of benthic algae and sediment will be included. In addition, the location of monitoring sites will target landscapes where land and water use are reasonably intense.