Te Waihora / Lake Ellesmere is an outstanding natural feature. It is a wetland of international importance and an area of immense cultural significance to
Ngāi Tahu. The waituna is fed by two small rivers,
Selwyn River / Waikirikiri and
Irwell River. These bring it a, comparatively, low volume of water, along with loads of silt and sand. At the coast, in an area known as
Canterbury Bight, a current runs parallel to the shore from south to north. This strong current brings with it sand and gravel sourced from the
Rakaia River. The bight is chronically eroding because its beaches are starved of sediment. The Rakaia River, incidentally, has a hapau at its mouth. Over geological time, a
spit grew, drift-aligned to the current. It was, initially, as to be expected, wide the southern end where it receives the most sand and gravel, and narrow at the northern end. However, as it grew, it bumped into
Banks Peninsula. This stopped it growing, but the sediment kept coming, so it no longer fits the rules of a spit. It's now wider at the
proximal end and narrower at the
distal end. It's become a barrier. Approximately 5000 years ago, it swung around, hinged at the point near Wairewa
marae on the shores of
Lake Forsyth / Waiwera. The barrier, named
Kaitorete Spit, even though it's a barrier not a spit, prevents the Selwyn / Waikirikiri and Irwell rivers from draining into the sea, and hence, a waituna sits behind the barrier. Its natural lake level is above
sea level. == Photographs ==