Toxic algal blooms continue to plague Lake Tutira as photos surface which show the stark reality of the state of the waterway.
In one of the photos [pictured above] the bloom covering the Lake has taken on a Van Goghesque appearance, a sickly version of Starry Night.
Regional council water quality and ecology scientist Dr Andy Hicks said the “surface scum” is part of the cyanobacterial [blue-green] bloom – a type of algae that is both toxic to dogs and humans.
“When the microscopic cells start to die and disintegrate, they form a bluish colour in contrast to the bright green colour of the living cells,” he said.
“The bubbly nature is probably an artefact of the dying and decaying cells trapping air bubbles as the organic matter interacts with the air-water interface at the surface of the lake and form a foamy scum.”
Council Chairman Rex Graham said the regional council was incredibly unhappy with the state of the waterway.
“The council takes the situation at Lake Tutira very, very seriously…it’s our number one priority,” he said.
He said that the council was very close to formulating a plan to address the myriad of issues the Lake faces – including multiple incidences of fish deaths - bringing together a range of different views.
“It is very complicated so we are spending a lot of time on this,” he said.
“Some very tough decisions need to be made.”
Hicks said that HBRC is working with a range of stakeholders including Maungaharuru-Tangitū, Fish and Game and the Department of Conservation to decide what to do to improve the quality of the lake.
“There has been a lot of research done to understand the problems in the lake and develop options to improve it,” he said.
“Water quality problems have been caused by a number of factors over decades and can’t be solved overnight.
“The issues have been caused by a range of factors including aerial top dressing in the 50s and nutrient leaching and sediment losses from some current farming practises.”
He said the catchment is very prone to erosion, such as Cyclone Bola which caused an estimate 773,000 cubic metres of sediment to enter the lake.
“Council established pine forestry in the catchment in 1992, and Manuka for honey production in 2012, to aid with soil conservation,” he said.
“Fencing and riparian enhancement work in the broader catchment continues.”
Dr Hicks said a variety of other options have been identified by modelling that was recently completed by the University of Waikato.
“But many options that should result in improvements are going to be costly so all stakeholders want to be certain they make the right choice before going ahead,” he said.
As part of the way forward, Graham said that the discussions will see stakeholders including farmers, fertiliser companies, Fonterra, iwi and the council sit down at the table together.
“We need a long-term remedy for the lake, we cannot continue to farm the way we are farming, to the detriment of the environment” he said.
“There is a lot of good will – everybody is putting their best foot forward.”
Last month the Hawke's Bay District Health Board’s medical officer of health Dr Nicholas Jones issued a warning about the algal blooms and warned people against having contact with the Lake’s water and to keep their pets away.
He also advised people not to eat fish from the water body.
In contrast, earlier this month Environment Minister Nick Smith announced under the government’s new water quality targets that the state of Lake Tutira was “fair”.