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phone: 9765 1200 | facsimile: 9765 1485 | P O Box 2 BOYUP BROOK 6244 | email: keith@boyupbrook.wa.gov.au |
Boyup Brook - Water Resources
Groundwater
The Shire of Boyup Brook lies within the upper reaches of the Blackwood and Collie River groundwater basins (as defined by the Western Australian Water Authority). Limited investigations have been undertaken into the groundwater resources within the Shire.
The Wilga Basin is divided into two distinct basins. The Wilga West basin has been estimated to be in the order of 6km x 3km in area and the Wilga East basin 10km x 1-2km in area. Little is known of the water quality of this basin, although available data suggests a moderate source of fresh groundwater. The Wilga Basin is estimated to have in the order of a 4 x 10 m average annual recharge with a possible groundwater in-storage of 390 x 10 m. Further testing has been suggested to determine the extent of resources.
The Boyup Basin is again in two distinct basins. The East Boyup basin is approximately 9 km x 0.5 - 2 km wide. Little is known of the West Boyup basin, although it is suggested that it may cover an area of approximately 2km. Available data indicates, “that a reasonable volume of fresh to brackish groundwater may exist within the Boyup Basin”.
With further exploration, it is anticipated that the volumes, recharge and water quality of the Wilga and Boyup Basins could provide substantial alternative water sources for future growth (including industrial) within the Shire.
Surface Water and Drainage
The major river system is the Blackwood River and its tributaries. Clearing of about 85% of the catchment of the Blackwood has resulted in a mean annual salinity level in the order of 1150 mg/litre total dissolved salt along its whole length. This is brackish water, which cannot be used for human consumption.
During winter many creeks are fresher than the Blackwood River. However by October, most creeks are far more saline than the Blackwood, with creeks that flow through summer having salinity readings between 2000 and 3780ms/ms. These creeks contribute to the rise and fall of the Blackwood River salinity levels. These salinity levels may continue to rise for many years as a result of past clearing.
The Collie River contributes to the catchment from the Northern area of the Shire and the Warren River contributes to the catchment of the South-eastern area of the Shire.