Collecting 29,000km of river condition data using LIDAR and aerial photography. (11529)
State-wide river condition in Victoria is assessed using a composite indicator of condition known as the Index of Stream Condition (ISC). The ISC brings together data from a variety of sources to give a detailed overview of river condition across the State. The ISC comprises five sub-indices – hydrology, streamside zone, physical form, water quality and aquatic life. State-wide assessments have been previously undertaken in 1999 and 2004. In the most recent assessment in 2010, data on the streamside zone and physical form sub-indices were collected using state of the art remote sensing technology (LiDAR and aerial photography). This was a major change from previous assessments which collected field data at 2,500 randomly selected sites. With this new technology, data was captured continuously along 29,000km of rivers and extending approximately 300m either side of the each river bank. This represented the largest operational use of these remote sensing technologies to assess river condition anywhere in Australia. There were considerable challenges in capturing the data within a limited timeframe and in automating the metric extraction process. The data is summarised every 100 metres and at the reach scale (typically 30km in length). This data will allow CMAs for the first time to have comprehensive and accurate information on streamside vegetation and physical form across their stream network at an operational level. This information will allow for a systematic assessment to determine priority sites where on-ground work needs to be undertaken and to more accurately determine the quantum of work and budgets required to meet the management targets. The LiDAR data is also being used to improve flood risk mapping and will underpin newly developed flood warning systems.