Three main rivers run down through the Puhipuhi-Whakapara-Hikurangi area:
- the Waiotu,
- the Waiariki,
- the Whakapara.
The red line on this picture shows the boundary within Puhipuhi for the De Gray Mining company to do its exploratory drilling.
The Waiotu drains the streams on the western side of the claim area, the Whakapara from the east; and the Waiariki from the middle.
Note the myriad of smaller streams and creeks which run through the entire catchment. There are numerous underground aquifers as well. These aquifers service the many bores which local communities use for their drinking and stock water.
The three main rivers join up to form the Wairua River which flows through the Hikurangi swamp. The Wairua is also joined by the Mangahahuru – one of the most polluted rivers in New Zealand.
These waters join up to form the Wairua River.
They also link into a myriad of underground aquifers along the way.
From the Hikurangi swamp, the Wairua flows down to the Wairoa River past Dargaville and out into the northern part of the Kaipara Harbour.
Other waterways are also connected to the Puhipuhi catchment. The Wairua River is joined by the Mangakahia in the west to become the Wairoa River. These waters are joined by waters from the Manganui and the Kaihu before they reach the Kaipara.
The Whangarei District Council is spending $14 million to build a treatment plant for the Wairua River as a back-up water source during drought periods (Whangarei Report 25 July 2013 pg 19)