Hartbeespoort Dam is one of the most significant dams in the economic hub of the North West Province. It is also a hypertrophic dam, meaning it contains excessive nutrients such as phosphates and nitrates. An Integrated Biological Remediation Programme, referred to as Harties, Metsi a me (My water) seeks solutions to the infamous water problems at the dam.
The remediation programme focuses on projects with short term results and three geographical zones.
The dam basin: restorative action and creation of biological self-cleaning balanced ecosystem will assist in bringing ecological balance.
Natural filters: restoring and protecting the wetlands and riverbanks in the immediate catchment.
Hartbeespoort Catchment: regulation of water use
The causes are many and complex, including:
Waste Water Treatment Plants discharge more than 700 million litres per day of treated effluent into the catchment , adding 280+ tons per annum of phosphate to the Dam.
Storm water washes surface pollution - e.g. sewage spillages, fertilizers, litter, animal waste etc. - into the Dam.
Grey water washes into the river where infrastructure is inadequate and rivers and streams are used as the only alternatives.
The natural purification capacity of the river banks, river beds and wetlands have been compromised by widespread modification.
Pollution is trapped in the sediments, and when disturbed, is released as an additional nutrient load into the water of the Dam.
The destruction of natural habitat of the shoreline vegetation contributes to a distorted food web and the dominance of three undesired fish species (Carp, Babel and Canary Kurper)
But the Metsi a me project is undaunted.
On 16 August a pilot project commences which tests the long term removal of sediments from the Crocodile river inlet.
A pilot dredging operation will extract small quantities of sediment at three locations in the Crocodile River and the dam. The dredged material will be contained into specially developed ponds on the properties of Roos se Oord and Oberon.
An information session is to be held on Wednesday, 18 August 2010, 12:00, at Roos se Oord for interested parties who wish to receive an on site briefing and view the equipment and a demonstration run.
In related news, the lobby group Environment and Conservation Association pursues criminal charges against Water and Environmental Affairs Minister Buyelwa Sonjica and President Jacob Zuma for their failure to uphold section 24 of the Constitution, which requires the government to protect water resources.
Acting DG Nobu Ngele of Department of Water Affairs (DWA) said that the department's enforcement unit continues to take legal steps against officials and the Madibeng Municipality, in particular, for allowing sewage from its wastewater treatment plant to pollute the Hartbeespoort dam.
The DWA had also allocated R500 000 to the Madibeng Municipality to enhance institutional capacity to deal with the problem and a further R27-million for a bulk water project, which included the expansion of the water purification works.