Integrated catchment management : Upper Denmark Catchment

The project mapped the landforms and land management units on cleared parts of the catchment ; defined the extent of, processes causing and options for solving the salinity problem in the Upper Denmark Catchment; developed a catchment management plan that would reverse the increasing soil and stream salinity trend within the catchment; encouraged and assisted the landholders to adopt the plan; and applied the results of the study to other areas

The salinity and hydrology of Cranbrook

The study area covers the Cranbrook townsite and two catchments that affect it. The Cranbrook Town is located 85 km north-north-west of Albany and it has a population of 320 people (1190 in the Shire; ABS Census 1991). Cranbrook is experiencing salinity problems. Saline groundwater levels are close to the soil surface and cause deterioration of buildings, roads, infrastructure, death of trees and scalding of land including the sporting ground

Salinity and hydrology of the Mills Lake Catchment

The Mills Lake Catchment is located north of the Ongerup-Jerramungup Road, 35 km west of Jerramungup and 10 km north-east of Ongerup. It covers about 23,800 ha of agricultural land that is more than 90% cleared and predominantly cropped. The average annual rainfall of the catchment is about 370 mm. Many low-lying parts of the study area have become salt-affected during recent years. The extent of soil salinity is growing rapidly and it is feared that, without any treatment, more land will become salt-affected

Salinity and hydrology of the Wamballup Swamp catchment

The Mills Lake Catchment is located north of the Ongerup-Jerramungup Road, 35 km west of Jerramungup and 10 km north-east of Ongerup. It covers about 23,800 ha of agricultural land that is more than 90% cleared and predominantly cropped. The average annual rainfall of the catchment is about 370 mm. Many low-lying parts of the study area have become salt-affected during recent years. The extent of soil salinity is growing rapidly and it is feared that, without any treatment, more land will become salt-affected

The salinity and hydrology of the Tambellup townsite and Jam Creek Catchment

The study area covers the Tambellup Town and the Jam Creek Catchment (top photograph on cover). The Tambellup Town is located 115 km north of Albany. The town has a population of 360 people (800 in the whole Shire). Tambellup is experiencing increasing salinity problems. Saline groundwater levels are close to the soil surface and cause deterioration of buildings, roads, infrastructure, death of trees and scalding of land including the sporting grounds. Many hectares of land in the Jam Creek Catchment has become salt-affected and salinity is on increase. The objective of this study was to define the present salinity status of the Tambellup Town and develop management strategies to overcome or reduce the severity of salinity. The Catchment Hydrology Group has been asked to study the salinity status of the Tambellup townsite and suggest management options which reverse the increasing salinity trend

Using natural resource inventory data to improve the management of dryland salinity in the Great Southern, Western Australia

The synoptic assessment of salinity risk and the likely costs and benefits associated with various management options is crucial to natural resource management decision-making in southern Australia. A variety of methods have been proposed and tested for assessing various aspects of salinity risks and costs, but no large region of Australia has ever had a comprehensive risk assessment across the range of biophysical and economic issues with forecasts of the effectiveness of different levels of intervention. This National Land and Water Resources Audit Implementation Project (referred to locally as Salt Scenarios 2020, or SS2020 for short) attempted to provide such an assessment (at a scale of around 1:100,000). The existing methods of monitoring and predicting salinity (based on variables derived from widely-available Landsat TM data and existing contour data; albeit with improved variable extraction from the DEMs) are being applied to the rest of the agricultural area of WA as part of the Land Monitor Project, funded in part by NHT. Collecting accurate contour data (2-metre) is a major part of the NHT project. This Audit project was proposed to allow other fundamental data sets, and especially groundwater levels from bore-hole data, to be used to significantly improve predictions in lower-rainfall areas as well as refine the predictions in the high rainfall areas. The Great Southern is an area of considerable economic and environmental value populated by 60,000 people. In 1996, it was estimated that about 30% of the cleared land and associated vegetation and water resources are at risk from becoming salt-affected over the next 30 years unless high-water use farming systems and farm forestry are adopted over large parts of the region(Ferdowsian et al., 1996). Four key questions arise with respect to the future of this region as affected by dryland salinity: •How large will the problem eventually be under current land practices? How large might it be in the year 2020? •What is at risk if the area under threat grows that large? •To what degree can we change the eventual extent of salinity with land use alternatives that are both feasible and available? •What are the costs and benefits of intervening with these alternative land uses? Ultimately, the SS2020 Project aimed to provide some guidance to state, regional and local planners and managers regarding salinity risk in the Great Southern. The analyses underpinning this guidance were based on similar data employed by NLWRA projects under Theme 2 – Dryland Salinit