Impofu’s decline paints dire picture

At the Impofu Dam, Nelson Mandela Bay’s biggest supply dam, at least 400m of dry veld stretches uphill from the present water line to where it was long ago — when it was full.

Speaking at the dam during a municipal tour ,on Thursday, water and sanitation director Barry Martin pointed out the spatial shift as a clear indicator of the dam’s decline in volume.

“Ever since the good rains we had in September 2018 all our dams have been dropping and today the Impofu is down to 16.6% of capacity,” he said.

“We are hoping that this will emphasise to all residents of Nelson Mandela Bay that they need to save water.

“We urgently need to reduce our consumption as a city from 300ML a day where we presently are to 250ML where we need to be.”

The Bay water supply system was highly integrated with flow from the western dams and the Nooitgedacht treatment works to the north criss-crossing the metro, he said.

“So there are no railway tracks here, no-one side of the city which will be fine while the others are not. We are all in this together.”

The average level for the metro dams was 26.6% on Monday, with the Kouga at 18%, Churchill at 82% and the Groendal at 38%.

Martin said residents should stick to the stipulated maximum of 50 litres per person a day and refrain from using hosepipes.

Although the Impofu is so low and the Churchill also on the Kromme River stands at a healthy 82%,  the Impofu is about three times the size, so the remaining volumes in each catchment are about the same.

The metro announced in November 2019 that the level of the Impofu had dropped below its intake pipes and a barge with an extraction pump was going to be floated to allow the last volumes to be harvested.

DA infrastructure and engineering spokesperson councillor Masixole Zinto  said the matter of the barge had in fact arisen in 2018.

Asked why this barge was not yet on the water, Martin said the vessel had not in fact been immediately necessary as sufficient water was being extracted from the Churchill, but it was now being repaired.

“It will be ready in six weeks’ time and once on the water it will allow us to extract down to 9%.”

Related to the call to save water, Martin and infrastructure and engineering political head Andile Lungisa were pressed on the proliferation of leaks around the metro.

An estimated 11,000 leaks amounting to 100ML of water lost a day were revealed in the municipal annual report presented to the council in January and subsequently to the infrastructure and engineering standing committee.

Asked if these figures were still correct, Lungisa did not answer directly, but said the metro had deployed extra personnel to deal with leaks.

Lungisa said the metro was looking to change the relevant bylaws to ensure new homes and businesses would be obliged to include water tanks.

The government would likewise be obliged to include these installations in its low-cost housing projects.

“We have to change the way we are living,” Lungisa said.

The infrastructure and engineering boss said the metro was also planning to establish a desalinator at Coega.

While this was a long-term vision, meetings were already taking place around this project.

He said the metro was busy with a suite of 100-odd boreholes, some on the ridge above the Churchill Dam and others in and around Nelson Mandela Bay, all of which would be used to augment the metros water supply.

Asked if this was a sustainable approach, Martin said a 2010 groundwater study had shown it was, but it would be combined with a replenishment system where water treated to an acceptable level would be injected back into aquifers.