Waikanae River is located on the

Kapiti Coast The Kapiti Coast District is a local government district of the Wellington Region in the lower North Island of New Zealand, 50 km north of Wellington City. The district is named after Kapiti Island, a prominent island offshore. The pop ...

in the North Island of

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

. The river drains the western flanks of the

Tararua Range The Tararua Range, often referred to as the Tararua Ranges or Tararua, is one of several mountain ranges in the North Island of New Zealand. The Tararua Range runs northeast–southwest for from near Palmerston North to the upper reaches of ...

s around Reikorangi and the Akatarawa Valley, then passes to the south of the town of Waikanae to the north of the river and Otaihanga/ Paraparaumu to the south before entering the

Tasman Sea The Tasman Sea ( Māori: ''Te Tai-o-Rēhua'', ) is a marginal sea of the South Pacific Ocean, situated between Australia and New Zealand. It measures about across and about from north to south. The sea was named after the Dutch explorer ...

at Waikanae - Paraparaumu Beach. Tributaries include the Maungakotukutuku Stream, Ngatiawa River, and Reikorangi Stream. The

estuary An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environm ...

of the river is a significant reserve providing shelter and habitat for local and migratory seabirds. It also provides a major recreational location, both for residents and tourists. Walking and cycling tracks are present on both sides of the river, leading from Waikanae Beach and Otaihanga Domain to the old state highway bridge just south Waikanae. Water up to a maximum amount is taken out of the river as water supply for Waikanae and

Paraparaumu Paraparaumu () is a town in the south-western North Island of New Zealand. It lies on the Kapiti Coast, north of the nation's capital city, Wellington. Like other towns in the area, it has a partner settlement at the coast called Paraparaumu Bea ...

. This sometimes leads to water restrictions if the river runs low, however in January 2005 the river burst its banks after heavy rain. The river has good water quality and high aquatic biodiversity, but there are occasional blooms of toxic cyanobacteria after prolonged periods of low flow during hot, dry weather. There have been multiple instances in earlier years (2020, 2021) where the river back has burst, leading to several floods in the elevated areas south of the river. It came with heavy rainfall and heavy storms and cyclones in the area. The estuary of the Waikanae River is ever changing, with major and minor storms disrupting the banks and causing it to change shape. Prior to storms in 2016/17, the river seamlessly transitioned into the sea, but after storms, long sandbars and banks have caused the river to take an winding path to reach the Tasman Sea.

Bridges

The first bridge was built about 1885 by the

Wellington and Manawatu Railway Company The Wellington and Manawatu Railway Company (WMR or W&MR) was a private railway company that built, owned and operated the Wellington-Manawatu railway line between Thorndon in Wellington, the capital of New Zealand, and Longburn, near Palmers ...

. It was a 3-span timber truss bridge. In 1925 a fence of old rails was built to protect the bridge, backed by fifteen old square iron tanks (sent from East Town), filled with river bed stones. By 1938 the bridge had been rebuilt in steel and concrete. The next bridge was built nearby and opened in 1901. It was also 3 timber spans and long. The latest bridge is on the

Kapiti Expressway The Kapiti Expressway is a four-lane grade-separated expressway on New Zealand's State Highway 1 route through the Kapiti Coast north of Wellington. From the northernmost terminus of the Transmission Gully Motorway at Mackays Crossing just no ...

. It is a single

T-beam A T-beam (or tee beam), used in construction, is a load-bearing structure of reinforced concrete, wood or metal, with a -shaped cross section. The top of the -shaped cross section serves as a flange or compression member in resisting compress ...

, above the river, with a span. There are also a couple walking bridges built by the Kapiti Coast District years ago on the river walking paths, such as the Otaihanga Domain Bridge.

References

External links

Photo of the Waikanae River from the Cyclopaedia of New Zealand c1897

* ttp://www.nzetc.org/tm/scholarly/Gov12_12Rail-fig-Gov12_12Rail041a.html Photo of the Waikanae rail and road bridges and express train leaving bridge c1938
South bank of Waikanae River with strata identified
* Rivers of the Wellington Region Kapiti Coast District Rivers of New Zealand {{Wellington-river-stub