THE world’s highest Piano Key Weir (PKW) dam, Hazelmere Dam, located on the Mdloti River in KwaZulu-Natal was commissioned by the Water and Sanitation Minister, Pemmy Majodina on 25 October 2024. The dam will improve bulk water supply to eThekwini Metro, and the iLembe and Kwa-Dakuza municipalities on the North Coast.
The commissioning of the state-of-the-art dam comes after the Department of Water and Sanitation successfully completed a project to raise the dam by seven metres to increase its capacity and to augment the water supply to areas such as Verulam, Groutville, Blythedale and Ballito.
Majodina emphasised the important role that municipalities have to play in order to ensure the reticulation of water to households.
“The Department of Water and Sanitation (DWS) upgraded the Hazelmere Dam to meet the needs of an increasing population on the North Coast as it is our role to ensure bulk water supply. The concerned municipalities should now roll up their sleeves to ensure that water is directed to households,” said Majodina.
The North Coast of KwaZulu-Natal has experienced rapid growth in recent years, especially in the residential sector which resulted in an increased demand for potable water. The raising of the dam wall will address water challenges in some parts of the three municipalities, according to the DWS.
The project scope of the work entailed the raising of the dam wall from 86m to 93m and this included the construction of retrofitting a Piano Key Weir (PKW) onto an existing dam spillway structure, the installation of 83 rock anchors as well as foundation grouting and other related works.
The Minister said, “The Hazelmere Dam can now be measured against world-class standards due to the type of spillway selection, technology and innovation used in implementing the project.”
The dam has an uncontrolled PKW spillway. This was created to ensure that the dam wall can withstand an extreme concentration of rainfall lasting between six and eight in its catchment area.
The DWS says some of the technologies employed in the upgrade include the construction of the world’s largest anchors which were installed to improve the stability of the concrete gravity dam wall structure. It says the largest capacity post-tensioning stressing jacks were deployed during construction.
Innovative data management software was used for real-time monitoring of anchor performance and 3D digital crack meters.
The upgrading of the wall assisted with the creation of employment opportunities for 187 locals of which 16 were women and 53 were youth. The total number of Small Micro Medium Enterprises (SMME) appointed were 11. Two were women-owned. In addition, the successful training of 14 engineers took place during the project, with some subsequently obtaining professional registration, marking a significant achievement in capacity building.
