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Bremer River Survey | March 2000 |
A foreshore survey was carried out by the Water and Rivers Commission throughout October 1999 to prioritise areas needing catchment repair. The resulting report is designed to provide a broad picture of the condition of the Bremer River and Devils Creek. Siltation, erosion and salinity are the most significant management issues present on both the Bremer River and Devils Creek, and weed infestation is an important issue, but one which is difficult to address in native vegetation communities with weed dominated understory.
The recommendations in the report mostly reflect the future plans of the landowners, money and time prevailing. These are positive actions to ensure the protection and restoration of the environments associated with the Bremer River and Devils Creek.
The focus area of the study was the main channel of the Bremer River, and the main tributary Devils Creek. The survey covered the channel embankments, floodplain, riparian zone and adjacent land use to the main channel of the waterways. The study area encompassed 23 landowners, all engaged in agricultural production. A small granite mine is also operating adjacent to the Bremer River.
The Bremer River Foreshore Survey was carried out using the Stream Foreshore Assessment and Survey technique devised by Pen and Scott as a guide. Aerial photographs of the properties were used for mapping. This involved recording:
To add a further dimension to the overall picture of the Bremer River, landowners provided information on historical and Aboriginal significance of the river, anecdotal recordings especially in regard to water quality, flora and fauna and their future management plans.
Stream Foreshore Assessment and Survey Technique
The Pen and Scott technique is an inexpensive and rapid means of assessing stream foreshore condition. However, it was developed from observations on rivers of the south west of Western Australia and was therefore adapted to suit the south coastal Bremer River. The assessment technique grades the condition of the foreshore from A (pristine) through B and C to D (completely degraded foreshore). The original technique breaks these grades down further, such as A1, A2, A3, B1, B2 etc. to provide a more detailed assessment, but for this survey a broad picture was required.
The grading system used was as follows:
The management issues faced by the landowners varies throughout the catchment due to the location within the catchment, past and current management practices, fencing status, and livestock access. Common problems were loss of native riparian vegetation, weed invasion, erosion and siltation, salinisation, increased patchiness of remnant vegetation and rubbish dumping. The landowners are concerned with the protection and restoration of the Bremer River and its tributary, Devils Creek, primarily because mismanagement can negatively impact on the agricultural productivity of the land. Those landowners who have not already done so, would like to fence out the Bremer River and Devils Creek, but concern over conditions, convenants and ownership, as well as farm priorities, money, time and the disruption to paddocks and existing fences hinder restoration work.
The survey report identifies numerous advantages to landholders from managing their riparian land with care:
The following general management techniques are recommended for the protection and restoration of the Bremer River and Devils Creek. Specific recommendations for each location are available in the survey report published by the Department of Environment.
