Is our water quality testing of Lake Hawea proactive enough, and are any measured tolerances of deemed good quality appropriate, given climate change.
If you thought that Lake Hawea hasn’t looked right for about a month now, you are not alone and probably not mistaken: pale blue green in colour rather than the normal pale to dark blue. The water is not clear around the edges.
A panorama of the lake last night shows the colour change quite clearly. Of special significance is the drop off in clarity from the, milky look (unusual) in the immediate foreground, going out a few meters to where obscurity now reigns…
This is how it used to look regrading colour and clarity, for years gone by…
The change appears timed with the end of the really hot weather during mid to late January with resulting increased lake water temperatures.
The poor water clarity can’t be explained by suspended mud (clay and mica mineralogy) as the lake has been low all summer with little in-flow. A sudden increase in water inflow, resulting in minimal lake level rise, in relation to the down-graded cyclone Fehi rain event took place after the change in lake water appearance. Furthermore, the lake water quality remained high all last 2016-2017 summer when high lake levels were sustained by north-westerly rain in tributary catchments.
Working on the suspicion that an algal bloom is the cause of the lake colour change, water samples were analysed under a microscope. As a possible cause to the change in lake water quality, a range of micro-organisms were identified including algae, dynoflaggellates and possible cyanobacteria. Whilst the preliminary study is only semi-quantitative, alarmingly the most abundant identified micro-organism is the possible cyanobacteria, the “blooming” of which is mostly likely to cause the current lake water discolouration.
The questions are:
Is the change in water quality only temporary and that it will revert to normal conditions once water temperature stratification is lost resulting in termination of the algal bloom (assuming it is the cause)?
If the lake water clarity does return to normal, will the deterioration be repeated with increased hot weather spells in future summers?
Are our current tolerances of nitrogen levels within the lake too high given the probable increase in mean summer water temperatures resulting in risk to further and perhaps more serious algal blooms.
Anthony Coote MSc (1st Class Hons) MBA, member AIG & SEG
A personal view by by Laurel Teirney, a former manager at Ministry of Fisheries
The success of the community based/scientist/agency approach we adopted for looking after the whole of the Fiordland, and then the Kaikoura Marine Areas makes me feel we’ve struck on a “magic” formula that just might apply to our lakes and rivers as well.
My passion, at the moment, is finding out if such an approach might work for lovely Lake Wanaka – because I have watched in dismay as numerous lakes and rivers have deteriorated in front of my eyes. So something about our current approach isn’t working for our waterways.
Lake Wanaka photo Laurel Teirney
There are those who say a combined community/scientist/agency approach will not work for this lake catchment – but why not give it a go? After all, what have we got to lose? And surely our lake deserves every effort to keep it in the low nutrient, high water quality category into the future for all our sakes!
Buff weka family feeding in Lake Wanaka shallows in 2008. This species which had become extinct were once common on the eastern South Island. They were reintroduced from the Chatham Islands onto Lake Wanaka’s Stevenson Island and nurtured in an aviary before releases on Te Pekekara and Waikatipu islands and to Mou Waho Island in Lake Wanaka, where they currently enjoy surprising picnicking visitors.
Obviously a healthy lake is paramount not only for the well-being of these very special birds, but other species as well, notably ourselves!
To me the fundamental principles of the approach to managing the Fiordland Marine Area are likely to be the same for lakes – indeed for any type of waterbody.
1] First, the approach is all inclusive – that is, tangata whenua and every “interest” is represented and everyone selects their own representatives.
Fishing boat in Preservation Inlet, Fiordland, with a cargo of cray “pots” [actually cages – lowered near rocks and pulled up again after a few days]. This is financially a high stress job, and dangerous. Also it’s a very different use of the environment compared to recreational fishing, and tourism
2] Then, when the representatives are around the table the first task is to agree on a shared vision. At our first Fiordland meeting in December 1995 there was a palpable sense of unease around the table. But when we went around the table and each person said how they wanted to see the Fiordland Marine Area in 20 years’ time, the unease was replaced by outright surprise – because everyone wanted the same thing!
A recreational diver in Preservation Inlet, Fiordland NZ. 2015. Diving for photos only due to it being a Marine Reserve, and as mentioned below not much is known about this area e.g. the fresh water layer here, on top of the salt water was approx. 5 meters, and nobody seemed to be aware of this – elsewhere it’s typically 1-2 meters
3] From then on, the primary focus stayed with the Fiordland Marine Area, not the desires of any participating group.
Dusky Sound, Fiordland
4] Given the isolation of Fiordland little had been documented about the marine area – so the priority was to gather together what was known. Following the shared vision at the first meeting a large map of Fiordland was laid on the floor. Each group was given different coloured dots and asked to place them on the map according to the locations they valued. Red rock lobster and purple paua dots appeared rapidly all along the coastline. But the blue recreational dots were slower in coming – as we all know rec fishers are a bit reluctant to share info about where they fish…..but when they considered what might happen if they didn’t show their dots they too were around the map and the shared observations and experiences filled the room. Only then did Stewart Bull of the Oraka/Aparima runanga, calmly walk up to the map and place a single yellow Ngai Tahu dot way out in the ocean. Silence fell and then some-one asked “Hey Stu what were you doing way out there?” And he calmly replied, “Oh just looking around”. And that set the tone for the rest of the process – lots of good humour and camaraderie.
Good humour is often evident in Fiordland, especially on the rare sunny day! A pessimist in Dusky Sound, Fiordland does therefore standout – near where Capt. Cook anchored up in Pickersgill Harbour for a month, after a circumnavigation up to three quarters of Antarctica.
One other experience of community knowledge that has stayed with me was the identification of the lines defining the inner fiords from the outer coast. I’ll never forget Pete Young, a blue cod and rock lobster fisher, standing at the maps marking exactly where those lines should be with input and encouragement from the rest of us. It wasn’t until several years later that Steve Wing, our marine scientist, produced data that simply reinforced the lines Pete had drawn.
No place to be in a 4 meter alloy tender with serious white water wanting to drive the bow under, and we’re upstream of a large rock, with all but 5 mm of it submerged – the head of Long Sound in Preservation Inlet, Fiordland
5] And so to the roles of the community and agencies involved. These were complementary right from the start and best described by an “egg analogy”. The yolk represents the community – all passion, commitment and knowledge about their place. The white represents the agencies – all support, advice and management tools for putting the management decisions in place. And there has been an additional benefit as the agencies now work in teams for every issue they deal with.
To me, this approach harnesses all the knowledge, all the passion and all the energy that leads to innovative solutions for even the most difficult issues.
And ongoing motivation is assured by the delight and reward of being involved in looking after one’s own place.
So my “dream” is to see many more of our waterways, be they lakes, rivers or marine areas looked after in such a way. Top of FormAnd logically, extending this from the mountains to the sea (ki uta ki tai), whole catchments could be managed in such a way – though the logistics are rather mind blowing I have to admit!
In the meantime though, I’m just going to continue advocating for a Lake Wanaka Community Management Plan.
The depth of water under the boat at Mou Waho Island on Lake Wanaka is deep enough to engender a sense of vertigo, it’s so clear. So “clear” that maybe we take it for granted!
Sunset – Dusky Sound, Fiordland, New Zealand
Unless stated otherwise all photo credits are Southern Light
More properly named the Te Waikoropupū Springs, they’re the largest freshwater springs in New Zealand, and the largest cold water springs in the Southern Hemisphere and contain some of the clearest water ever measured this side of Antarctica’s near-frozen Weddell Sea, with a visibility of 63 metres.
Antarctica aside the water clarity is in fact not equalled anywhere in the world, and is the result of natural filtering prior to the water’s emergence at Te Waikoropupu Springs.
What we’ve taken for granted for many years is now under threat, and what it’s all about is allocation of water upstream for agricultural use.
It’s not rocket science to ponder that the issue really comes back to what runs into the source areas e.g. nitrates from farming operations.
Read more about it via the link below to a post published by Radio NZ today:
Race to protect Te Waikoropupū Springs
The guardians of Te Waikoropupū Springs in Golden Bay are urging the Environment Minister to preserve and protect it from commercial ventures.
New Zealand's clean green image personified in the Strath Taieri ~ photo Southern Light
For the third summer running now in Mt Aspiring National Park, I interact with many tourists intent on being the overseas equivalent of a New Zealand tramper.
Most know our “Clean Green” marketing ploy is not what it seems, and that New Zealand is perceived as just one big farm. To think otherwise ignores the profound “connectedness” the Internet has on the sharing of information world wide.
We’ve got an awful lot of work to do in some areas to live up to the marketing, but really I hope our motivation is otherwise with more of a flavour of health and well-being!
This aside ‘tho it’s kinda weird that politicians are still stuck in a retro ten to twenty year time warp, totally out of touch with our visitors. The inference being also out of touch with our landscape!
In this post I want to present two views – neither particularly extreme. Lets have the good news first:
Water quality good for summer swimming | Otago Daily Times Online News
Water quality in Otago has been good so far this summer, Otago Regional Council (ORC) seasonal recreational water quality testing shows. Three sites have had alert/amber warnings at certain times since the summer round of testing began at the beginning of
… which reinforces my experience that Regional Councils and associated environmental dept’s, ie Environment Southland, many farmers, and New Zealand’s Dept. of Conservation do an extremely good job not only keeping us safe, but in the facilitation of our summer enjoyment. Much of this work goes unnoticed and unsung!
By contrast, and almost on the same day, we have the below opinion on our “Clean Green Image”. After reading it please leave a comment with your views or experiences in your neighbourhood
Dialogue: An environmental crisis second to none – Environment – NZ Herald News
It’s the time of year to get close to nature. Forest & Bird has thoughtfully released a list of 10 places (“New Zealand’s hidden treasures”) where families can do just that. Except that none of the country’s numerous lakes, rivers or streams are named among them.
The Lord of the Rings actor and New Zealand tour guide operator Bruce Hopkins is not surprised, calling our rivers and lakes “gutter holes” and “sewer pipes”. He slams the “clean green” image behind the 100% Pure New Zealand promotion.
Acting Tourism Minister Paula Bennett has defended it, saying: “It’s an award-winning campaign that is working brilliantly for New Zealand with record growth in visitor numbers.”It’s not, and never has been, an environmental measure.”
Hopkins believes “we are leaning towards being deceptive around how we sell ourselves as a tourist destination”.
A heads up for residents of Wanaka and Albert Town, and all who care about the health of rivers such as the Clutha…
Goldfish believed illegally dumped into Albert Town’s artificial wetlands are breeding and some have found their way into the natural lagoon beside the Clutha River.Now, environmental agencies are concerned the bottom-grazing pest fish may soon invade the already degraded Clutha River, which has been infested by didymo for about 10 years.