Rand Water is battling water supply challenges amid power failures and high water consumption during Gauteng’s heatwave.

On January 29, water pumping from Rand Water’s Eikenhof booster station was impacted by a power failure, resulting in a depletion of Rand Water’s reservoir levels and leaving some reservoirs at 0% storage level.

The steady drop in reservoir storage levels, recorded at 76% on January 8, started on January 9, owing to high water abstraction by municipalities from the reservoirs.

Rand Water explains that purified water is pumped from the Zuikerbosch and Vereeniging purification plants, which has a maximum water treatment capacity of 5 000 megalitres of water a day, to the Eikenhof, Mapleton, Palmiet and Zwartkopjes pump stations, before being pumped to 59 water storage reservoirs in its distribution network from which municipalities receive water to distribute to residents.

The system, however, is “extremely” sensitive to any power outage and may take a minimum of four hours to recover after an outage.

On January 13, power supply failures impacted the Zuikerbosch purification plant and Eikenhof pump station, with reservoir storage levels dropping to 63% when the system recovered.

According to Rand Water, the power outage incident affected Zuikerbosch pumping station at its Engine Room 4, which supplies almost 40% of Rand Water’s capacity, lasted six hours.

This affected pumping to its pump stations that feed water into reservoirs.

A power outage at the Eikenhof booster station impacted the system for three hours, making it impossible to feed water into the reservoirs.

“The drop in water storage level in the reservoir resulted in Rand Water requesting municipalities to reduce their consumption to retain as much water in the reservoirs and ensure the system does not drop to a point of crushing and almost impossible recovery,” Rand Water said in a statement on Monday.

However, this did not assist in that high-water abstraction continued dropping the reservoir storage levels further and had stabilised at about 30%.

At this low level. there were other reservoirs that were significantly impacted to be below 15%, at which point municipalities start experiencing inadequate to no supply to high lying areas in their networks.

“Rand Water continued engaging with its customers through meetings and formal letters to request them to monitor water consumption in their respective areas and effect the necessary measures to manage high water consumption during the heatwave.”

While Rand Water is completing its generator installation project aimed at reducing the power outages, generator capacity will not cover all Rand Water sites and power outages remain one of the biggest threats to the stability of its networks as it affects continuous water supply to municipalities.

“Rand Water systems have started stabilising pumping at maximum capacity. Full recovery, however, will be dependent on less frequent power failures. In the meantime, Rand Water urges all consumers to use water wisely to assist in the system full recovery.”