Hot Spot Projects
HBRC’s annual plan has identified six environmental hot spots that need attention.
- Lake Tūtira
- Ahuriri Estuary
- Whakaki Lake & Wairoa River
- Whatuma and the Tukituki Catchment
- Karamu Stream
- Marine Environment
Improving water quality in Lake Tutira
The lakes have been by affected poor water quality and algal blooms for decades - the first algal bloom was recorded in 1957. This is not an overnight problem, and there’s no single cause. Rain washes soil and nutrients from fertiliser into the lake from the surrounding landscape, plus a ‘legacy load’, a build up over decades, of soil and fertiliser nutrients sits in the lake bed - both these reduce water quality and feed algal blooms.
What we are doing?
Air Curtain - An air curtain is being trialled in Waikōpiro Lake at Tūtira this summer (installed 21st September 2017) as work continues towards improving the water quality in the area. The trial is being undertaken as part of Te Waiū o Tūtira (the milk of Tūtira) project, which is a partnership between Maungaharuru-Tangitū Trust and Hawke’s Bay Regional Council aimed at restoring the mauri of Lakes Waikōpiro and Tūtira.
A lack of oxygen and the lake water heating up over summer has been a major factor causing algal blooms and the death of fish, which has left the lakes largely out of bounds to those who enjoy camping, swimming and boating in the area. Blooms can also turn toxic and pose risk to human and dog health.
What is it and what will it do? - Pressurised air will be pumped through a 50-metre pipe tethered close to the bottom of lake and across the deepest part, creating an air curtain. The air curtain increases oxygen levels at all depths throughout the lake by creating a circulation current, much like bubblers in a fish aquarium. The system is being piloted in the smaller Waikōpiro, and if successful a larger air curtain will be installed in Tūtira Lake.
The air curtain has been constructed on-site by HBRC’s Works Group staff, mostly out of parts found in any hardware store.