Geomorphic baseline study in Kathleen Valley
Kathleen Valley is in the arid Murchison bioregion. It depends on ephemeral streams that briefly recharge groundwater reserves during the wet season, which makes the landscape sensitive to changes in water flow and sediment movement.
A targeted geomorphic survey was carried out to gather baseline data relevant to the potential impacts of a proposed mining development and its infrastructure.
Survey focus
The survey was commissioned at the request of the Tjiwarl Traditional Owners. It focused on parts of a nearby culturally significant water body that are prone to erosion or flooding, so that environmental planning addresses the areas of greatest ecological and cultural concern.
In the field, the team collected 12 sediment samples from priority zones and noted where distinct soil layers changed. This information helps establish the geological profile of the watercourse.
Monitoring sites were also identified for future observation. These will allow changes to the sediment profile to be recorded visually over time, for use in community-led initiatives and consultant-supported ecological assessments.
Sample analysis
After the fieldwork, the team analysed the collected samples to assess their vulnerability to bedload movement (the movement of sediment along the bottom of the watercourse).
Each sample was sieved to sort the sediment by size, and the composition by weight was compared across sites. The aim was to identify trends in composition and determine which areas were most at risk of flooding and which were more resilient.
Conversations with the Tjiwarl Traditional Owners during the work added their knowledge of the land to the ecological data.
Contact us to discuss hydrology and sediment surveys.
