27 May 2012
Grand Lake St Mary’s suffered horribly and long from algal blooms during 2011 – and the warnings are already up at four beaches, heralding a dismal year for recreation at this popular lake in Ohio.
Warning signs will be placed at the four beaches where algae educational signs already are up. The educational signs, which show what algae looks like and tell people how to report it, were placed at Grand Lake and several other lakes across the state that have had algae problems.
The new signs will read “Warning – High levels of algal toxins have been detected. Swimming and wading are not recommended for the very young, the very old and those with compromised immune systems.”
In Kansas, warnings are in place at Great Bend (Memorial Lake) and Marion Reservoir, while in Oklahoma an alert has been posted for Eufaula Lake while Lakes Ellsworth and Lawtonka have been given the ‘all-clear’.
In the UK, early emergence of blue-green algae has brought a halt to water sports at Killingworth Lake in North Tyneside. Talkin Tarn in north Cumbria is also off-limits.
And in Australia, despite the cooling temperatures, Lake Burley Griffin (no stranger to Droplets reports) is again off-limits as algal levels exceed 1000 times the specified safe limits!
Here in Southern Africa, speculation points to Botswana as the first likely victim of a water shortage crisis.
And, finally, in Denver (USA, Colorado) debate is ensuing about the validity of reducing nutrient levels in wastewater in order to protect local waterways! We will still see a lot of these arguments before the penny drops.
27 May 2012
A couple of days ago I mentioned the amazing decision by Canada to terminate the world’s largest and longest running experiment on lake management, the Experimental Lakes Area (ELA) project.
As someone living in a country (South Africa) which is still suffering from the fall-out of an equally short-sighted decision – the willful ignorance and deliberate non-disclosure of the Williams Report being just one facet), I can only join in condemning such a short-sighted decision. The need for informed lake management is increasing, not decreasing.
SIL, the International Society for Limnology, is correct in taking a stance on this issue. I have copied hereunder the note sent by the SIL President, Professor Brian Moss, to its membership. The NOAA have echoed this concern.
Read more »
23 May 2012
Quite a few articles are doing the rounds about an organochlorine (DDT family) agrochemical fungicide with the chemical name chlorothalonil. A recent research paper has linked it to serious impacts on a range of aquatic organisms, a claim refuted (obviously) by the manufacturers. Apparently this compound is still registered for use in South Africa (?)
23 May 2012
St Mary Lake in Vancouver has worked up some cyanotoxin levels, enough to get the lake closed almost before the season has started [Source: GulfIslandsDriftwood].
Total microcystin levels in untreated water tested by the Highland Water Service District between December 12, 2011 and April 17, 2012 have ranged from 19.41 ug/L (micrograms per litre) to 30.8 ug/L. According to World Health Organization recommendations established in 2003, recreational exposure to microcystin concentrations greater than 20 ug/L represent a health risk to humans. The WHO suggests contact with water containing more than 20 ug/L of microcystin be avoided. Read more »
23 May 2012
South Africa's lake management skills: Time to re-build (Photo: Bill Harding)
Fact: South Africa is dependent on water stored in dams
Fact: Many of South Africa’s dams are extremely polluted
Fact: Dams (reservoirs) should be managed as functional, healthy semi-natural ecosystems
Fact: South Africa has allowed local reservoir-management skills to almost disappear
Scary but true. Not too long ago, South Africa was a place where aquatic scientists from other countries came to learn. The CSIR, in its erstwhile and rightful guise, as a provider of government-funded, top-class research, encompassed the National Institute for Water Research, augmented by nearby institutes for chemistry and microbiology – one did not have to walk far down the passage or across the lawn to tap into the brain of someone who could provide advice. Around this hub were aligned various research units at Universities. Research units at some of the bigger local authorities, such as Cape Town, were described as rivaling some overseas universities.
All gone now. Following the metamorphosis of the CSIR into a flashy consultancy, with profit-driven motives, coupled with the willful denial of the need to continue reservoir research, those scientists who did not emigrate moved into consultancy-operations. Secure salaries were replaced by the need to make money and the opportunity to walk down the passage and enjoy the benefits of working amongst like-minded specialists, all disappeared. River science and, much later, wetland science, predominated to the near-exclusion of anything to do with dams, despite the latter being a key nodal point along river systems. But all of this was mostly consultancy-driven which, in terms of skills development, is mostly a one-way street that leads away from building a national memory of skills and experience. Read more »
22 May 2012
Foodweb schematic for Rietvlei (Harding and Hart, 2012)
South African limnologists Bill Harding and Rob Hart have just completed thirty months of research testing a new (for South Africa at least) approach for determining the structure of the foodwebs in our dams. The work was conducted at Rietvlei, east of Pretoria. The work was funded by the Water Research Commission. Read more »
21 May 2012
Diatoms are powerful indicators of water quality (Photo: Bill Harding)
Diatoms provide probably the most powerful biological indicator for assessing water quality in streams, rivers and wetlands. Additionally, they can be used in a paleoecological application to determine historical conditions, an attribute which can be used in climate change assessments. Globally, there is a massive database of information which supports the cosmopolitan use of these algae in aquatic assessments.
The culmination of a programme of research and method development, led by Bill Harding from DH Environmental Consulting, has been the formulation of the South African Diatom Index (SADI), a tool which allows the numerical composition of diatoms, collected from a specific site, to be translated into a value representing the water quality (and a whole lot of other ecological inferences as well simply not available from any other bio-indicator approaches). Read more »
20 May 2012
The first reported animal death incident from the US occurred this week in Oklahoma at Lake Ellsworth. Two dogs died soon after ingesting algal scum at the lake. Very sad to hear and lets hope that the unfortunate loss of two beloved pets leads to a greater level of public awareness about the causes and effects of nutrient enrichment in lakes and rivers worldwide! Read more »
20 May 2012
A bit more than a year ago I postulated a 10-point approach for how South Africa should consider getting to grips with the management of our eutrophication problem. Since then there have been quite a few responses to that, none from South Africa incidentally, from a lot of people with similar problems who have found the advice very useful.
Recently I was approached by Cambridge University Press regarding their inclusion of the plan, as posted on Droplets, in a new textbook entitled “Environmental Systems and Societies for the IB Diploma“, authored by Paul Guinness and Brenda Walpole.
All good news and Droplets continues to contribute to training and skills programs worldwide!
7 May 2012
Photo: Bill Harding
After many months of warnings, there now appears to be a general agreement that South Africa faces a massive water crisis. No less a source than the Minister of Water Affairs (DWA) has acknowledged that something urgently needs to be done to offset a “near crisis situation”. But, a major component of the problem, managing our dams, continues to be ignored. Read more »