Flows in the Olifants River reached alarmingly low levels in January of 2018, and the levels of the Blyde Dam are also worrying, so all water users in the Olifants Catchment should act to reduce water consumption before the situation gets worse.
This is the message from Dr. Sharon Pollard, the Director of The Association for Water and Rural Development (AWARD). “The data on the river flows shows that were it not for the intervention of AWARD and SANParks together with DWS to release water from the De Hoop Dam, it is likely that flows in the lower Olifants River would be close to zero,” she notes, adding that all indications are that the crippling drought of 2016 – 2017 has continued into 2018, despite rains elsewhere.
While DWS has yet to formally gazette a drought for the area, as of the 6th of February 2017 “we have received 54% less rainfall in comparison to the same period last year, and 59% less than the long term average,” she notes, adding that rainfall measurements by Hoedspruit locals and AWARD up to the same date have recorded around 95 mm of rain over this ‘rainy season’, far below the average of 560 mm.
Sharon has been working with a team of experts on the USAID-supported Resilim O project in the Olifants River Catchment to help understand its vulnerabilities and to make it more resilient to changes, especially in a climate changing world. Monitoring and helping to manage river flows as been an early success of the project, which has had three monitoring stations installed on the Olifants River at Oxford (near three Bridges), Mamba (at the Phalaborwa entrance to Kruger) and Balule (near the Mozambique border) which monitor flows in real-time.
This is a first for South Africa and results are available to the public through AWARD’s recently released app called FlowTracker which is available free of charge ( https://play.google.com/store/apps/details?id=flowtracker.award.org.za.flowtracker). A more detailed platform has also been developed and is being used to train DWS staff.
Ensuring that flow and water quality can be tracked in the lower Olifants is critical to understanding whether or not flows comply with a ‘sustainability minimum’ known in South Africa as the Reserve. “As a legal requirement, the Reserve refers to the quantity – and quality – of water to meet basic human needs and to sustain a healthy river that continues to provide for us,” explains Sharon. “Importantly we focused on the need to track flows in real time so that if there is a problem action can be taken immediately,” she adds.
“Until we requested a release from De-Hoop Dam there was a possibility that the Olifants would have stopped flowing but with these releases we are just meeting the minimum drought requirements. Near Hoedspruit, flows in the first week of February were sitting at 2 m3/s – half of what even the minimum requirements are,” she notes.
In the wet season (normally between Oct and March) flows to meet the Reserve should be around 8.2 m3/s (or 8200 litres per second). This excludes the water needed for Lepelle Northern Water who supply domestic water to greater Phalaborwa and the mines. Under drought conditions (which have not been declared), the flow is set at a minimum of 4.3 m3/s.
With neither of these values being met with flows into Kruger sitting as low as 1 m3/s in late January, the De Hoop release bought a bit of a reprieve for the river and those who rely on it.
The situation remains serious though, with flows still dangerously low.
“Hoedspruit residents should also remember that much of our water in the lower Olifants is supplied by the Blyde river from Blyde Dam. However water levels in the dam are also worrying given that we are at the end of the rainy season when the dams would have been filled,” says Sharon.
“The Blyde Dam, at 64% as of 6 February, was at 100 % levels last year at the same date. Since the Blyde Dam is filled purely by rainfall in the upper catchment, it is inherently vulnerable to low flow conditions,” she explains. Hoedspruit’s water supply is also sourced from the Blyde Dam via the Drakensig air force base, making the town vulnerable to low flow conditions too.
Whilst Drakensig have imposed restrictions, it is up to the municipality to regulate water use in Hoedspruit town. Likewise in Phalaborwa and other towns the municipalities need to impose and regulate water use.