The Bloukrans River is sick. This is the finding of a practical project carried out by third-year Botany students in August.
The Bloukrans River is sick. This is the finding of a practical project carried out by third-year Botany students in August.
A recent post on the Grahamstown Residents’ Association (GRA) FaceBook page about the poor state of the Belmont Valley Water Treatment Works (BVTW) prompted the students to test the water quality of the Bloukrans River in the Belmont Valley at three different locations along the river as part of their aquatic ecology course.
Sage Wansell, one of the students, reports here that the organisms living in the Bloukrans River live in a quality of water that we would shudder to drink.
The water quality was tested by performing a miniSASS test (http://www.minisass.org), a simple tool to monitor the health of a river based on the presence of macro invertebrates (small organisms and insects) sensitive to water quality.
These are assigned scores that indicate the condition of the aquatic ecosystem. In a rocky river environment (as in the), a score below 5.1 indicates that the river is in a very poor condition whereas a score greater than 7.9 indicates that the river is in its natural condition with a healthy ecosystem.
At the first test site, located above the BVWTW, the river was highly polluted with plastic, organic waste and other litter. The students sampled the macro invertebrates and calculated a miniSASS score of 3.5, indicating very poor water quality.
The second test site, below the BVTW, had a score of 2.1 indicating poorer river health due to run-off of sewage from the BVWTW and fertilisers from nearby farms.
The bright red blood worms found at this site live in oxygen-poor environments, being one of the few creatures that can tolerate the current condition of the river.
The Bloukrans River showed some resilience to the pollution at the third site, which registered a higher miniSASS score of 4.1.
While this score is still off the scale compared to the ideal score of a healthy river, the presence of more macro invertebrates living lower down the river indicates that the ecosystem is trying to remedy its unhealthy state.
In addition, the students found that the total dissolved oxygen content in the river water at all three sites was low (20–25 percent), indicating oxygen environments too low to support a healthy ecosystem.
The high concentrations of total dissolved solids, 850–986 ppm, indicate the high amount of chemicals and other components from detergents, sewage leakage, fertilisers and other waste in the water.
The river also contains extremely high amounts of nitrates in the water, due to the presence of fertilisers and sewage.
Such high levels of nutrients can cause aquatic creatures to become extinct in an ecosystem.
The students concluded that the Bloukrans river ecosystem is in dire need of help. As a community, we have the power and responsibility to help prevent the river from being damaged further.
To help minimise these detrimental effects, we must stop littering, illegal dumping and pouring unwanted fluids down the drain.
We can also organise clean-ups along the river. And Makana Municipality should make serious efforts to have an efficient waste management system. Alternative “eco-friendly” approaches can be used for waste management and disposal; for example, the sewage sludge can be treated using worm farming.
On a broader scale, “composting toilets” (outdoor facilities) can be installed in rural areas to reduce waste that would otherwise end up in landfills or as effluent.
Creation of a forest!
The kloof forests on our Southern Commonage are disappearing fast due to frequent fires that are destroying the forest margins.
Rivendell Farm, in Howiesons Poort, was one of the areas badly burnt in the June 2016 wildfire. Nick James reports that Rivendell is doing an experimental forest regeneration project of about 1ha of forest margin that was virtually destroyed in the fire.
This area has now been cleared of all bracken and alien vegetation (the combustible element that allows fire to penetrate the forest margins), and over 300 indigenous trees planted over the area.
Fire-resistant trees such as Rhus species are planted along the edges to create natural fire breaks.
The bracken will be kept cut up to the point when the trees canopy together and shade it out, then the forest cannot burn.
About half the trees were donated by Albany Working for Water, and the balance grown from seed at Rivendell.
It is a labour of love. We will keep you posted on progress!
Find us Online:
www.grocotts.co.za/environews
Contacts for Makana Enviro-News:
Nikki Köhly: n.kohly@ru.ac.za, 046 603 7205 |
Jenny Gon: j-gon@intekom.co.za, 046 622 5822 |
Nick James: nickjames@intekom.co.za, 082 575 9781 |
Philip Machanick: p.machanick@ru.ac.za, 046 603 8635 |
Tim Bull: timothybull05@aol.com, 076 289 5122;
Rod Amner r.amner@ru.ac.za, 046 603 7123.
