The Rees River (Māori language: Puahiri or Puahere)[1] is a headwater tributary of the Clutha River / Mata-Au that drains eastward of the main divide of the Southern Alps / Kā Tiritiri o te Moana in New Zealand. The river runs 41 km,[2] drains an area of 406 km2, and discharges into the head of Lake Wakatipu at Glenorchy. Bound by the Richardson (Whakaari) Mountains[3] to the east and the Forbes Mountains[4] to the west, its snow-covered headwaters rise above 2000 m.
The upper parts of the Rees River occupy a formerly glaciated valley that was fed by the Tyndall Glacier, which now drains into the adjacent Dart Valley. Below Rees Saddle the river valley is constrained by a series of steep alluvial fans that are fed from tributary basins.[2] The lithology of the Rees catchment is highly erodible schist of the Aspiring lithologic association.[5] The underlying schist is highly fissive due to its fine-grain, segregated quart-feldspar-mica composition.[6]
The Rees valley, covered in tussock and native forest, is a popular location for recreational fly fishing, pack rafting and tramping, including the Rees and Dart Tracks, a five-day loop which crosses from the upper reaches of the Rees into the valley of the Dart River / Te Awa Whakatipu.[7] However, the steep hillsides, easily erodible rock, proximity to the Alpine Fault, and intense rainfalls contribute to geohazard risks in the region. A debris flow swept away a hiker during a river crossing in an unnamed tributary in the Upper Rees Valley near Cleft Peak in January 2002.[6]
The Rees river and valley get their gazetted name[8] from the high country station, was originally part of the runs established by William Gilbert Rees, the first sheep farmer in the Wakatipu Basin.[9] Ownership of the station has been in the Scott family since 1905; the Rees Valley Station is maintained in perpetuity as a part of Crown Pastoral Lease.
In popular culture
The lower Rees Valley, which continues to operate as a beef and sheep grazing farm, was a filming location for Mission: Impossible – Fallout,[10] and the television drama series Top of the Lake.
^Turnbull, I. M. (2000). Geology of the Wakatipu Area, Institute of Geological and Nuclear Sciences 1:250,000 geological map 18. 1 sheet + 72 p. Lower Hutt, New Zealand, Institute of Geological and Nuclear Limited.
^ abMcSaveney, M.J., Glassey, P.J. 2002. The fatal Cleft Peak debris flow of 3 January 2002, Upper Rees Valley, West Otago Institute of Geological & Nuclear Sciences science report 2002/03. 28 p.
