Application Report

Place: Roodeplaat Dam, Pretoria, South Africa

Date: 6 March 2020 - 8 March 2020

Background:

Roodeplaat Dam is a 4.4 Sq-km multipurpose dam (lake), located in the vicinity of Pretoria, South Africa (Fig. 1). It is a major source of potable water, serving three highly populated provinces, and is also used for recreational purposes as the only Olympic rowing venue in South Africa.

The World Master Regatta Organizing Committee asked BlueGreen to treat the lake prior to the competitions held on March 6-8, 2020.

• The lake was treated with Lake Guard^TM Oxy for mitigating a severe bloom of Microcystis (Fig. 2A) during the fourth week of February, 2020.
• The treatment reduced the total biomass of the cyanobacteria by 99.99% over the course of several days (Fig. 2B).
• No adverse effects on fauna or flora were observed, further confirming the safety of the Lake Guard^TM
• As of January 2021, the lake is still clean since the treatment was carried out, for the first time in the last two years.

Fig. 1. An aerial photo of Roodeplaat Dam displaying areas of severe Microcystis algal bloom.

Fig 2. A remote sensing image using Lakeguard View^TM of the algal bloom prior to (C-F),  and after the LakeGuard^TM treatment (A-B).

(A) Dec 2020,  (B) Dec 2019, (C) Dec 2018, (D) Dec 2017, (E) Dec 2016 and (F) Dec 2015

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