Big Bang to happen in Lake Michigan

4 April 2012

Invasive fish are a problem in parts of Lake Michigan – and scientists have brought in a big (underwater) gun to try and frighten them off.  “It’s worth a shot” noted an observer.  I am not sure how this will work and selectively affect problem fish and not desirables, but lets wait and see.  In my experience birds and animals get used to this type of thing and simply ignore it after a while.  It does sound a bit desperate but presumably they have a precedent that indicates it may work.  [Source:] Read more »

Security companies ignore basic worker’s rights

4 April 2012

Imagine spending a twelve-hour shift in this? (Photo: Bill Harding)

Travellers along the N2 highway between Somerset West and Cape Town may have noticed little, brown, toilet-sized huts – and I use the term “hut” with a lot of latitude as it is notional at best – dotted along route of the Eskom power lines.  These “shelters” house security guards, usually two in a space that one person struggles to fit into, who carry out 12-hour shifts guarding the power lines against cable theft.  This they do, in all weathers, 24 hours a day.  Their only weapons are two-way radios.  They have been there for years. Read more »

Town gets funds to restore disused sewage works to remove phosphorus

3 April 2012

You might be surprised by how many US towns are named “Watertown”, but the one in South Dakota has been awarded a grant to to convert a disused sewage works to remove phosphorus currently getting into Lake Kampeska [Source:].  Some years ago I suggested a similar approach for a disused works upstream of Hartbeespoort Dam, South Africa – but there was not much interest.  There are a number of disused “smaller” treatment works in many areas, taken out of use as newer, bigger treatment plants were constructed.  It makes a lot of sense to use these, with all their tanks and ponds, for a positive application such as the removal of environmentally-harmful nutrients. Read more »

Ensuring the future quality of water supplies: Pay now or pay (more) later?

2 April 2012

This has been a recurring theme on Droplets.  More and more municipalities and regulators become aware of the risks posed by eutrophication, and the need to reduce the nutrient levels to offset algal blooms and water treatment problems and costs.  In many cases the costs of doing so are far from insignificant and are being strenuously resisted. Read more »

Will treating AMD be delayed by devious dealings?

2 April 2012

Most South Africans are aware of the regional Water Crisis in Gauteng posed by the rapidly-rising levels of acidic mine water, scheduled to start to spill over as acid mine drainage, sometime this year.  This issue has been at the forefront of press reporting for a couple of years now, as have some details of what is being done to deal with the problem. Read more »

Stormwater management to be funded by levies on properties

1 April 2012

Here’s an approach that may bring the need for proper stormwater management into the minds of the homeowner.  While we already pay a levy, based on water consumption, for sewage treatment (not sure that this has produced any benefits yet), homeowners in Fairfax County, Virginia, will soon pay a ‘stormwater tax”, based on the assessed value of their properties. [Source: TheConnection]

…Fairfax County taxpayers may have to fork over more money this year for stormwater management. County Executive Tony Griffin has proposed an increase of one penny on the real-estate tax for a total of 2.5 cents for every $100 of assessed value. The average homeowner would see a $45 increase over the course of a year. The new rate would generate about $35 million, which would be used to meet the flood of new federal and state requirements on [the] storm-sewer system. Read more »

Maryland approves floating islands for stormwater management

1 April 2012

Large floating island with young trees (Source: FII)

The BioHaven range of floating islands constitute the single greatest advance in wetland and waterway management.  The technology provides a true form of ‘biomimicking’ coupled with durability and a wide-range of user applications.  Expensive, yes, but the value for money is not in any doubt.

The floating wetlands cost between $25 and $32 per square foot for materials. A 200-square-foot project would cost about $8,000 to $10,000 including permits, anchoring and other costs.  That [tiny] size floating wetland would trap about 150 pounds of nitrogen each year.  And for each acre of water, about 660 square feet of floating wetland is needed. Read more »

Problems in Cape Town’s Zandvlei not helped by confused reporting

1 April 2012

Zandvlei - surrounded by development (Photo: Martin Pollack)

A recent report on apparent algal problems in Zandvlei has sown some confusion.  In an article about renewed efforts to protect South African estuaries, a news report noted that

Fish are dying off in the estuary and the lack of oxygen in the water has contributed to growth of algae blooms in the estuary

OK, so what is wrong with the statement.  It’s back to front!  Algal blooms can cause a drop in oxygen levels, which can lead to fish kills.  A lack of oxygen does not contribute to algal growth!  This what happens when reporters don’t bother to check their statements before going to press.  The big danger is that once the wrong ideas become lodged in the minds of the public, its difficult to get them corrected.

It is also very important not to ‘over-react’ to fish kill incidents.  A lot of very good management and monitoring guidelines have been developed for Zandvlei – sticking to them is vital.

Read more »

Cape Town’s reporting on algae getting better, but still needs work to be accurate

1 April 2012

The City of Cape Town recently reported on a bloom of a cylindrical, filamentous diatom in their Molteno Reservoir [Source: Water Rhapsody].  They correctly indicate that there are no known health problems associated with this benthic (bottom-dwelling) alga – which, en masse, can cause considerable problems in the flocculation systems of water treatment works.   Read more »

Lake management interventions ready themselves for the 2012 summer

1 April 2012

While we in South Africa watch our days get shorter and cooler, many US states are preparing for the hot season, and the conditions in their lakes.  Droplets readers will have followed the many lakes in the US and elsewhere that suffered from algal blooms, and associated economic loss, during the 2011 peak season.  Many of them are not keen for that to happen again. Read more »