Water weir woes
FEARS have been allayed that a major disruption at the Mhlathuze weir last week could affect the city’s entire domestic and industrial water supply.
This follows an incident late on Wednesday evening when an underground spring forced large amounts of water up to the surface, collapsing part of the bridge at the weir.
According to Mhlathuze
Water, the underground disturbance, which they described as ‘a water seepage’, was discovered by contractors working on alterations and additions to the existing weir to improve its overall efficiency.
A widely circulated video showed intense activity, with the water bursting upwards like a flash flood.
An emergency evacuation plan was initiated to ensure no harm befell the workers and engineers on site.
In a statement, Mhlathuze Water said prompt action, which included temporarily opening of the sluice gates to release water pressure from upstream which could otherwise have resulted in physical damage to the weir structure, was taken to ensure no damage was done to the environment and that the supply of water was not interrupted.
Emergency measures in place to avoid water supply interruptions
‘Mhlathuze Water wants to reassure its customers and the public that measures are in place to ensure that there are no interruptions to the water supply while engineers work on identifying and repairing the source of the seepage.
‘In the intervening period, Lake Nsezi is being used to supply water.
‘While the incident does not pose any significant environmental threat, Mhlathuze Water has taken all the necessary precautions to monitor the situation, including working closely with the national Department of Environmental Affairs and the Department of Water and Sanitation,’ the statement read.
Mhlathuze Water Corporate Communications Manager, Siyabonga Maphumulo, said it was anticipated that the pump station would be fully operational within a week.
‘Neither plant, equipment nor human lives were lost in the incident. While one plant was temporarily submerged in water overnight, the process of removing it has already started,’ he said.
However, questions remain unanswered as to whether the construction work in progress above the weir had contributed to the incident.
Water is pumped from the Mhlathuze weir to Lake Nsezi from where it is reticulated via the treatment plant.
When full, the lake holds a supply of water that can last about 40 days without augmentation.
Thanks to the late rains which filled the city’s dams, which were almost empty as a result of the drought, there is no immediate threat to water availability.
‘Being in the water, weirs by nature are always fragile and under stress, especially since rivers are subject to flooding,’ said one experienced engineer.
‘The Mhlathuze weir is about 30 years old and is in constant need of monitoring and maintenance.
‘Inherent risks during any construction work must be mitigated.’
The Mhlathuze River flows under the John Ross Parkway and into the Port of Richards Bay. Damage caused by the incident can clearly be seen (circled) at the Mhlathuze weir, from where the river water is pumped to Lake Nsezi Bryce Forduce