Waingaro River (Waikato)


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. Its main tributary is Kahuhuru Stream, which Highway 22 follows for several kilometres. Tributaries total about. At Waingaro it is fed by a hot spring.

Geology

The lower river flows over Puaroan age, blue-grey Puti siltstone.

Pollution

The Waingaro River is one of the largest sources of sediment in Whaingaroa Harbour, partly because it is 99 percent unfenced.
Pollution has been worsening for phosphorus, though nitrogen has improved, as shown in this table of important improvements, or deteriorations in relative seasonal Kendall slope estimator trends - Turbidity is also poor.
% per yearNitrate-NTotal phosphorusDissolved reactive P
1993–20171.0-1.0-1.0
2008–2017-3.4