STATEMENT: Status of Water Resources as of 10th September 2021

STATEMENT: Status of Water Resources as of 10th September 2021

STATEMENT: Status of Water Resources as of 10th September 2021

Issued by Shami Harichunder, Corporate Stakeholder Manager, Umgeni Water

Rains during the past weekend and early this week have pushed up the levels of the four dams in the Middle South Coast. By Friday, 10th September 2021, the dams in that region – Nungwane, Umzinto, EJ Smith and Mhlabatshane – were in excess of 100% and overflowing. These dams supply the towns of Umzinto, Park Rynie, Pennington, Scottburgh and surrounding villages.

Rainfall recorded month to date (1st September 2021 to the present) at monitoring stations close to the Middle South Coast dams amounted collectively to 196 mm. A total of 70 mm was received at Amanzimtoti; this is lost to rivers and streams as there no dams close to Amanzimtoti.

The other dam that is overflowing is Home Farm in Ixopo, which supplies the town of Ixopo and surrounding areas. Approximately 48 mm rainfall from 1st September 2021 to the present has resulted in this dam reaching 110%, from 109% a week ago.

In the vast Mgeni System, a total of 246 mm rainfall has been received month to date. However, this has not made a significant difference to the levels of the six dams in this system,  namely Mearns, Spring Grove, Midmar, Albert Falls, Nagle and Inanda. On Friday, 10th September 2021, the levels of dams in the Mgeni System were at:

  • Spring Grove: 82% and unchanged from a week ago
  • Mearns: 90%, representing an increase of 8% from a week ago
  • Midmar: 92% and unchanged from a week ago
  • Albert Falls: 49% and unchanged from a week ago
  • Nagle: 92% and unchanged from a week ago
  • Inanda: 87% and unchanged from a week ago

The level of Midmar Dam is being supported by pumping from Spring Grove and Mearns. Albert Falls – the largest dam in KwaZulu-Natal – remains of concern to Umgeni Water because it has been at below 50% for approximately six years. Water is being pumped from Midmar Dam and water transfers are occurring from Inanda Dam to stabilise the level of Albert Falls Dam.

Total raw water storage in the entire Mgeni System is at 76%, which is considered acceptable and there is no risk of water supply shortages occurring in the short to medium-term. The Mgeni System supplies the municipalities of uMgungundlovu, Msunduzi and eThekwini.

Month to date rainfall in the Hazelmere System has been estimated at 50 mm, and the level of Hazelmere Dam was at 37% on 10th September 2021. This level is unchanged from a week ago. Further north, in Maphumulo, iMvutshane Dam was at 52%, an increase of 1% from a week ago.

Hazelmere Dam supplies the water needs of the north of eThekwini, including Verulam, and parts of iLembe, including Ballito, while iMvutshane Dam supplies the Maphumulo area.

There is adequate raw water in this system to meet current, short and medium treatment needs.

The storage capacity of Hazelmere Dam has been more than doubled through raising of the dam wall. The current level of 37% translates into 80% based on its previous storage.

Umgeni Water has released its quarterly analysis of water resources within its supply area and projections on rainfall for the spring and early summer months.

As expected, the amount of rainfall received during May and June 2021 in the entire Umgeni Water supply area was below average.

However, the outlook for spring and the first half of summer is above average rainfall. This is good news because, if it materialises, dam levels will increase rapidly, thereby improving water resource adequacy.