Hundreds of thousands of KwaZulu-Natal residents and holidaymakers are likely to celebrate Christmas without running water as electricity-powered engines are unable to pump water due to load shedding. 

On Sunday, State-owned water entity Umgeni Water announced that load shedding was affecting supply of drinking water to municipalities within Umgeni Water’s service area. 

The entity said that hundreds of thousands of consumers within the uMgungundlovu, Msunduzi, iLembe, Ugu, Harry Gwala, King Cetshwayo and eThekwini municipalities were unable to receive drinking water during and after load shedding.

This comes as the country continues to grapple with one of its worst energy crises in years with multiple power cuts each day. 

Eskom spokesperson Sikhonathi Mantshantsha declined to comment. 

In a statement, Umgeni Water complained: "Eskom applies various stages of load shedding and of late it ramped up loadshedding to Stages 5 and 6, creating power supply cut-offs in some instances for up to six hours per day.

"When power supply is restored, it takes at least an hour for the supply mechanisms, both in the bulk and reticulation networks, to return to full functionality. In the meantime, what little storage remains in reservoirs begin emptying out and there is no accompanying replenishment. This leads to supply interruptions to consumers."

In the Mgeni System, the largest system in KwaZulu-Natal, the areas worst affected by water supply failures through power supply interruptions are Vulindlela, Mpophomeni and Hilton, all of which are high-lying and dependent on the Howick West Reservoir for potable water transferred through a system of pumping.

Other areas that don't receive water during load shedding are KwaHaza, KwaChief and Mashingini, said Umgeni in a statement. 

It added that all areas in Impendle were affected while in the Mpofana system, Bruntville is often starved of water supply when power supply disruptions occur.

The Midmar Pump Station and the Midmar Water Treatment Works were excluded from load shedding and conveyance of raw water and its treatment were unaffected. 

When power outages occurred, downstream Millfalls Reservoir was able to receive water from the Midmar Water Treatment Works and it, in turn, was able to transfer the water to the Howick West Reservoir, the entity revealed.

The water remained in the Howick West Reservoir until power supply was restored, it explained.

Consequently, the reservoirs of uMgungundlovu District Municipality and Msunduzi Local Municipality in Vulindlela were unable to supply water to consumers in the vast area of Vulindlela.

Water was pumped from the Groenkloof Reservoir in Hilton to Vulindlela.

Hilton was affected when power supply outages occurred.

The reservoir in Richmond also relied on the Midmar Water Treatment Works supply zone.

It was affected because water has to be pumped there as well.

Areas within Richmond that were affected by no water supply were Ndaleni, Nhlazuka and Mbutshisweni.

Water from the Midmar Water Treatment Works is gravity-fed to the eThekwini Metro, which can receive full supply during load shedding to distribute to various areas, including Mid-Illovo, Eston, Umbumbulu and Hillcrest.

The DV Harris Water Treatment Works, in the outskirts of Pietermaritzburg and part of the Mgeni System, continues to take the brunt during power shut-offs.

This plant supplies Umgeni Water’s seven reservoirs in the uMshwathi Region through pumping.

All the receiving bulk and reticulation reservoirs in uMshwathi are left without water.

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In the Durban Central Region, the Durban Heights Water Treatment Works has two incomers, one of which has been excluded from load shedding.

The exemption includes all production units, shaft pumping and the KwaDabeka Pump Station.

The section that has not been excluded affects feed to the Pinetown Pump Station, which means no pumping can occur. 

The interconnected Wiggins Water Treatment Works in Bonella, Durban, has been exempt from load shedding.

This system supplies potable water to central Durban. It also augments the Amanzimtoti Water Treatment Works through a system of gravity feed and pumping.

At times of load shedding, transfer of water from the Wiggins Water Treatment Works to the Amanzimtoti Water Treatment Works is interrupted, exacerbating the deficit that already exists at the Amanzimtoti Water Treatment Works. 

The Umzinto Water Treatment Works loses approximately 30% in potable water production during load shedding periods.

When load shedding occurs, generators are used in what becomes a slow and long process that often produces yields less than the required volumes. 

Mid-South Coast systems’ full recovery time post-load shedding is, on average, two hours.

The water treatment plants in the King Cetshwayo District that are operated and managed by Umgeni Water are affected during power supply stoppages because they do not have stand-by generators. This means the potable water that is produced cannot leave the plants and the Water Services Authority does not have adequate water to distribute to consumers in Eshowe and surrounding areas.

The Ixopo Water Treatment Works, within Harry Gwala District Municipality, remains fully functional because it uses a diesel-powered generator during load shedding.