The Waihou River is located in the northern

North Island The North Island ( , 'the fish of Māui', historically New Ulster) is one of the two main islands of New Zealand, islands of New Zealand, separated from the larger but less populous South Island by Cook Strait. With an area of , it is the List ...

of New Zealand. Its former name, Thames River, was bestowed by Captain

James Cook Captain (Royal Navy), Captain James Cook (7 November 1728 – 14 February 1779) was a British Royal Navy officer, explorer, and cartographer famous for his three voyages of exploration to the Pacific and Southern Oceans, conducted between 176 ...

in November 1769, when he explored of the river from the mouth. An older Māori name was "Wai Kahou Rounga". A 1947 Geographic Board enquiry ruled that the official name would be Waihou.

Geography

The river flows north for from the

Mamaku Ranges The Mamaku Ranges are a mountain range in the North Island of New Zealand. Located to the west of Lake Rotorua and north of Lake Taupō, they lie to the immediate south of the Kaimai Range and can be thought of as an extension of it, in much the ...

past the towns of

Putāruru Putāruru is a small town in the South Waikato District and the Waikato region of New Zealand's North Island. It lies on the western side of the Mamaku Ranges and in the upper basin of the Waihou River. It is on the Oraka Stream 65 kilometres s ...

Te Aroha Te Aroha is a rural town in the Waikato region of New Zealand with a population of 3,906 people in the 2013 census, an increase of 138 people since 2006. It is northeast of Hamilton, New Zealand, Hamilton and south of Thames, New Zealand, T ...

Paeroa Paeroa is a town in the Hauraki District of the Waikato Region in the North Island of New Zealand. Located at the base of the Coromandel Peninsula, it is close to the junction of the Waihou River and Ohinemuri River, and is approximately 20 kil ...

and

Turua Turua is a small village community on the banks of the Waihou River in the Hauraki Plains in the North Island of New Zealand. It is located close to the mouth of the river, 9 kilometres south of the Firth of Thames and 12 km south of Thames, ...

, before reaching the

Firth of Thames The Firth of Thames () is a large bay located in the north of the North Island of New Zealand. It is the firth of the rivers Waihou and Piako, the former of which was formerly named the Thames River, and the town of Thames lies on its south ...

at the south end of the

Hauraki Gulf The Hauraki Gulf / Tīkapa Moana is a coastal feature of the North Island of New Zealand. It has an area of 4000 km2,Thames, New Zealand, Thames. In its lower reaches, the river and the nearby

Piako River The Piako River is a lowland river system that drains into the Firth of Thames on the North Island of New Zealand. Together with the Waihou River, it is one of the two main rivers systems which drains the Hauraki Plains. It is the dominant ri ...

form the wide

alluvial Alluvium (, ) is loose clay, silt, sand, or gravel that has been deposited by running water in a stream bed, on a floodplain, in an alluvial fan or beach, or in similar settings. Alluvium is also sometimes called alluvial deposit. Alluvium is ...

Hauraki Plains The Hauraki Plains are a geographical area located in the northern North Island of New Zealand, at the lower (northern) end of the Thames Valley, New Zealand, Thames Valley. They are located 75 kilometres south-east of Auckland, at the foot of ...

. Just before the river reaches the ocean, State Highway 25 crosses the river over the Kopu Bridge, which was the longest single lane bridge in the country at and the only remaining

swing bridge A swing bridge (or swing span bridge) is a movable bridge that can be rotated horizontally around a vertical axis. It has as its primary structural support a vertical locating pin and support ring, usually at or near to its center of gravit ...

on a New Zealand state highway. The bridge was infamous for the queues of vehicles travelling to and from the

Coromandel Peninsula The Coromandel Peninsula () on the North Island of New Zealand extends north from the western end of the Bay of Plenty, forming a natural barrier protecting the Hauraki Gulf and the Firth of Thames in the west from the Pacific Ocean ...

until a new two lane bridge was opened in December 2011. Tributaries include the Waimakariri Stream, Waiomou Stream, Oraka Stream and the Ohinemuri River.

History

Many areas on the banks of the Waihou River were settled by

Hauraki Māori The Hauraki Māori are a group of Māori iwi Iwi () are the largest social units in New Zealand Māori society. In Māori, roughly means or , and is often translated as "tribe". The word is both singular and plural in the Māori language, ...

, such as Oruarangi pā and Paterangi pā near

Matatoki Matatoki is a locality on the Hauraki Plains of New Zealand. It lies on State Highway 26, south east of Thames and north of Paeroa. The Matatoki Stream runs from the Coromandel Range through the area to join the Waihou River. The Kopu sawmill, ...

, and the Te Raupa pā and Waiwhau pā near

. The mouth of the river was famous as a location for pātiki (flounder) fishing. In 1879 Te Au o Tonga, or the Falls of Awotonga, were destroyed by of

dynamite Dynamite is an explosive made of nitroglycerin, sorbents (such as powdered shells or clay), and Stabilizer (chemistry), stabilizers. It was invented by the Swedish people, Swedish chemist and engineer Alfred Nobel in Geesthacht, Northern German ...

to free the navigation of the river for shipping. There was a water column of . Other parts of the river had been cleared in the same manner in previous years. Josiah Firth spent £7,442 to 1880, extending navigation for his Kotuku steamer, drawing , as far as Stanley Landing, near Gordon. By 1923 a launch could reach

Okauia Okauia is a rural settlement and community located east of Matamata, in the Waikato region of New Zealand's North Island. The New Zealand Ministry for Culture and Heritage gives a translation of "place of articles threaded on a stick" for ''Ōk ...

. A 1925 report said there had once been a steady traffic. Regular traffic on the river ended in 1947. In the 1910s stopbanks and floodgates were constructed along the Waihou River in order to protect farmland from flooding, including a canal constructed at the point where the Waihou River and Ohinemuri River meet, west of

. Further work occurred in the 1980s after extensive flooding in 1981.

Recreation

The river supports large populations of

rainbow A rainbow is an optical phenomenon caused by refraction, internal reflection and dispersion of light in water droplets resulting in a continuous spectrum of light appearing in the sky. The rainbow takes the form of a multicoloured circular ...

and

brown trout The brown trout (''Salmo trutta'') is a species of salmonid ray-finned fish and the most widely distributed species of the genus ''Salmo'', endemic to most of Europe, West Asia and parts of North Africa, and has been widely introduced globally ...

. A survey conducted in 2009 showed that the upper section of the river supported over 700 fish per kilometre.

Pollution

The water quality at Te Aroha is in the worst category for dissolved reactive

phosphorus Phosphorus is a chemical element; it has Chemical symbol, symbol P and atomic number 15. All elemental forms of phosphorus are highly Reactivity (chemistry), reactive and are therefore never found in nature. They can nevertheless be prepared ar ...

and also the worst 25% of all sites measured for other pollutants. At Okauia the river is in the worst category for ''

E. coli ''Escherichia coli'' ( )Wells, J. C. (2000) Longman Pronunciation Dictionary. Harlow ngland Pearson Education Ltd. is a gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus ''Escherichia'' that is commonly foun ...

'', though the measurement may have been overestimated. In the upper reaches of the river the main pollutant is phosphorus. Water flows are measured at Te Aroha and Okauia.

References

External links

*
1:50,000 map of source of Waihou RiverSouth Waikato District Council: Te Waihou Walkway to Blue Spring - with link to youtube video
Thames-Coromandel District Rivers of Waikato Rivers of New Zealand Firth of Thames Hauraki Gulf catchment Waihou River catchment {{Waikato-river-stub