Wainui River (Bay of Plenty) river. Wainui River (Bay of Plenty) The Wainui River is a river of the Bay of Plenty Region of New Zealand's North Island. It flows north from the Kaimai Range to reach Tauranga Harbour south of Katikati. The catchment has of stream margins. 41% of the catchment remains covered in native bush, but 48% is under pasture and suffers soil erosion. The river includes 3 waterfalls of up to , which have been kayaked. The long former East Coast Main Trunk railway bridge is designated as the limit of the Coastal Marine Area. Downstream, a 3-span bridge takes SH2 over
Bay of Plenty 259 km of open coastline used for economic, recreational and cultural purposes. The coastline from Waihi Beach in the west to Opape is defined as sandy coast, while the coast from Opape to Cape Runaway is rocky shore. Sizeable harbours are located at Tauranga, Whakatane and Ohiwa. Major estuaries include Maketu, Little Waihi, Whakatane, Waiotahe and Waioeka/Otara. Eight major rivers empty into the bay from inland catchments, including the Wairoa, Kaituna, Tarawera, Rangitaiki, Whakatane, Waioeka, Motu and Raukokore rivers. The region has more than 200 km² of lakes, known as the Lakes of Rotorua. Much of the central part of