The Waingaro River is a river of the Waikato region of New Zealand's North Island. It flows generally southwest from its origins near Glen Afton and Glen Massey, west of Ngāruawāhia, to reach a northern arm of Raglan Harbour (see 1:50,000 map). Its main tributary is Kahuhuru Stream, which Highway 22 follows for several kilometres. Tributaries total about .Land Air Water Aotearoa At Waingaro it is fed by a hot spring.
Geology
The lower river flows over Puaroan age (about 150 million years ago), blue-grey Puti siltstone.Geology of the Raglan-Kawhia Area: Institute of Geological & Nuclear Sciences (N.Z.), Barry Clayton Waterhouse, P. J. White 1994
Pollution The Waingaro River is one of the largest sources of sediment in Whaingaroa Harbour, partly because it is 99 percent unfenced.Regional Council report on Whaingaroa Harbour Care
Pollution has been worsening for phosphorus, though nitrogen has improved, as shown in this table of important (i.e. slope direction probability over 95% and RSKSE over ±1% pa) improvements, or deteriorations (-) in relative seasonal Kendall slope estimator (RSKSE) trends (monthly records are flow-adjusted using a Lowess curve fit with 30% span.) - Turbidity is also poor. % per yearNitrate-NTotal phosphorusDissolved reactive P1993–20171.0 -1.0 -1.02008–2017 -3.4
See also List of rivers of New Zealand
References
New Zealand 1:50000 Topographic Map Series sheet BD32 – Raglan
External links
most of the river is close to Ohautira and Waingaro Roads, so many images are available in street scene on https://maps.google.com/ water quality at Ruakiwi Rd LAWA WRC water level at Waingaro , , - National Library 1910 photos of Waingaro Landing, Waingaro Bay (note the 1900 road to the Landing on the hillside) and Waingaro Estuary. 1955 Waingaro Landing aerial photo - the foreground shows part of the Kerikeri River arm of the harbour, which is over 3 km long. The Waingaro River joins the estuary in the middle left of the photo. Photo of oil launch 'Nita'. 2012 Estuarine Vegetation Survey - page 15 describes the wildlife in the Waingaro and Kerikeri River arm of the harbour.