“If its green on top, stop” – lake users warned

31 August 2012

“If its green on top, stop” is the warning communicated to Oklahoma lake users ahead of the upcoming holiday.  The www.checkmyoklake.com site has all the details.

This (northern hemisphere) summer has been all reports from North America.  Either there have been very few blooms in Europe or else they are not being reported on – I must check with my colleagues over there.  Today, however,  there is a warning for Lake Alster in Hamburg, Germany. Read more »

It is possible to grow fish and not pollute the environment

30 August 2012


High fish production without the “green”

Aquaculture is not very scientific and includes a big risk of polluting the environment.  Fish are put into floating cages and then food is thrown at them- which they eat and convert into nutrient-rich excreta which, together with the uneaten food, pushes up the nutrient levels in the surrounding water.  This is fine in fast-flowing, well-flushed environments but in many there is the risk of algae build-up and the production of sales-affecting tastes and odours and even toxins.

BioHavens have changed all this. Read more »

Dog lucky to survive encounter with toxic algae: England’s waterways full of algae

30 August 2012

The owners of a dog in Surrey, England, were lucky to get their dog to a vet in time to save its life after it swam in a pond full of toxic algae.  The dog spent 36 hours on a drip and was fortunate to recover.  Most don’t.  Local residents are upset about the apparent inadequacy of the warning signage.  At least there was some – over here in South Africa reservoirs can be full of toxic algae without any warnings whatsoever! Read more »

Shoprite launches floating islands

30 August 2012

Final planting prior to positioning (Photo: L Muller)

Two BioHaven floating islands were launched this week at the DH Environmental-designed stormwater treatment facility for the new Shoprite centre in Parklands, north of Cape Town.  A total of 480 sq feet of islands, providing a massive 11 000 sq meters (yes, meters) of submerged surface area, were planted up and positioned in the treatment pond. Read more »

BioHaven floating islands add to their product range

29 August 2012

Some of the BioHaven product range

Something akin to the “wetland in a bag” concept introduced in South Africa by DH Environmental Consulting, Floating Island International have introduced another product known as ‘Freshwater Coral”.  This comes in various forms, most recently in chains of bags as shown in the images below. Read more »

How credible are the claims made by the Hartbeespoort Dam remediation project?

29 August 2012


Some members of the original Remediation Project team led by Bill Harding of DH Environmental Consulting. (left) Pirjo Kuupo (Finland), (right) Jeff Thornton (USA), with Garry MacKay (HWAG), standing in front of the pipe that transports sewage from Johannesburg North to the sewage works (2004).

This week I attended a very pleasing workshop tasked with seeking ways to broaden the understanding of eutrophication, or nutrient-enrichment, of South African reservoirs.  At this meeting I chanced across some documentation dealing with the reservoir-rehabilitation work being undertaken at the notorious Hartbeespoort Dam.

As the senior author of the Hartbeespoort Dam Remediation Plan, undertaken by my company between 2003 and 2005 and which set the scene for what has happened subsequently, I naturally have a professional interest in what is happening and what has been achieved at the dam.  However, as I and most of my project team colleagues were excluded from further involvement once we completed our work, we have to rely on the paltry amount of information, near-total lack of any reporting and much rumour, that has emerged from the project to-date.  This exclusion of an informed body of specialization conflicts with the importance of such interaction claimed in the article referred to below. Read more »

South Africa takes first steps towards raising awareness of the eutrophication threat

28 August 2012

Today I participated in a one-day workshop aimed at enabling an environment that will support efforts to tackle the problem of eutrophication in South Africa.

I must say that I came away from this meeting with more hope than I had initially anticipated.  Not only was the process capably and efficiently run by a small team of staffers from the Water Research Commission, there were clear signs that attention is being paid to uncovering a topic that has been underplayed for so long.

There is a still a lot to do and the mechanics of how to place eutrophication on the radar of decision-makers poses all sorts of problems.  Time will tell but I sincerely hope that we, as a country, have finally turned a corner on this topic.  I look forward to being able to participate further. Read more »

South Africa enters into dialogue about how to address eutrophication

27 August 2012

Tuesday August 28th will see the beginning of what will hopefully become a national dialogue about the problems posed by eutrophication in South Africa’s dams and rivers.  This is a long time coming and maybe, just maybe, we will see the overt admissions about the problem that our Department of Water Affairs needs to make.

I have been appealing for attention to this very topic since 1990 and will again provide some input to tomorrow’s workshop hosted by the Water Research Commission in Pretoria. As background to the guidance I hope to be able to give, I have compiled a background document detailing some of the reasons why we have not done this decades ago.  The article is entitled Eutrophication Management in South Africa: Reasons Behind the Inability to Transition from Science to Practice.

(Bill Harding is a professional lake biologist who was first confronted by the ravages of eutrophication as a student working for the CSIR in 1995)

Yet another floating island success story!

27 August 2012

BioHaven floating islands have been installed in ponds at the Virginia Zoo in Norfolk, similar to those shown above in the Lincoln Zoo. In southeastern Virginia, these grant-funded islands have been planted and are being studied and evaluated at the College of William and Mary in Williamsburg, Virginia Institute of Marine Science at Gloucester Point and the Virginia Zoo in Norfolk.

Plants placed in the holes establish a hanging network of roots and rhizomes that help filter pollutants. The islands can function in any water depth, and are usually planted with native species – cardinal flower, irises, sedges and grasses – that can also be enjoyed in home gardens.

“Since we began the study in late April this year, we have noted other functions of the floating wetlands,” says William and Mary professor Randy Chambers.

Snakes, frogs and turtles used the wetland in addition to birds.

“Both great blue herons and little green herons have been attracted to and land on the floating treatment wetland to feed,” Chambers said. “We also observed a red-tailed hawk catching a water snake in the wetland; hummingbirds frequent the cardinal flowers.”

A stormwater pond known on campus as “Grim Dell” due to its dismal appearance, now attracts people who watch and take pictures of wildlife attracted to the floating island.

W&M student Katherine Thomas, in charge of monitoring water quality in the pond, applauds the project because no independent research has been done on these floating wetlands. She feels the entire country can benefit from what’s been tested locally.

“Since these stormwater ponds are all over the country, it would be ideal if we could use floating wetlands for habitats, aesthetics and water quality improvement,” she said. “Overall, we would just like to make something more useful out of these human-created stormwater ponds.”

Two islands totalling 736 square feet also were installed on the Elizabeth River. Within 24 hours, a mallard built a nest and laid an egg among the hibiscus, lizard’s tail, bulrush, cattail and sweet flag, according to project leaders.

An 80-square-foot island was installed at Kinder Morgan Elizabeth River Terminals, and a smaller one was put in a homeowner’s backyard pond in April.

For information on BioHavens in South Africa, please contact DH Environmental Consulting at info@dhec.co.za.

Beware of imitations!

Eutrophication threatens 10 million residents of Shanghai

25 August 2012

Shanghai’s major source of drinking water to 10 million residents, is under threat from the effects of uncontained eutrophication. The condition of the water at the mouth of the Yangtze River, where the Qingcaosha Reservoir is located, is threatened mainly by chemical plants along the river, such as the Japanese paper mill in neighboring Jiangsu Province.  The reservoir was completed as recently as 2010, at a cost of US$2.7 billion. Read more »