Southland region

The Aparima River headwaters drain alpine, native tussock and forest land on the eastern flanks of the Takatimu Mountains at an altitude of 1500-1600m above sea level. The Taringatura Hills and the foothills of the Takitimu Mountains constrain the Aparima River in its middle reaches. In its mid to lower reaches, the Aparima River has assisted in the formation of the western Southland Plains through the transportation of large volumes of gravel from its headwaters. Also of note is the Castle Downs Swamp, one of the largest remaining wetland areas in the Southland region. Nestled at the base of the northern extent of the Taringatura Hills and hemmed in by the Aparima River and Hamilton Burn, the Castle Downs Swamp covers an area of approximately 12 km2. Environment Southland has several permanent water level and automatic rainfall recording sites in the Aparima surface water zone. These sites are not only for floodwarning purposes but also to increase knowledge of the flow regime and water balance throughout the catchment. Daily rainfall records are also collected by members of the public. At present, the Aparima WRZ has low levels of surface water allocation. The majority of water use is in the lower reaches, near Gummies Bush, where the township of Riverton abstracts water for its municipal supply. In the upper Aparima catchment at Dunrobin, a water level recorder provides early warning of flood peaks coming down the catchment, which allows farmers time to move stock to higher ground.