Reader Brian Finch wrote in to ask a question about where the Umgeni emptied into the sea:
Allan
I would be pleased if you could settle a matter of fact for me re the Umgeni River mouth.
I have always understood that the Umgeni River originally fed into Durban Bay ( now harbour) and that it`s present mouth at Blue Lagoon is a fairly `recent` change. Am I right and if so, when and how did the river course change ?
Brian
I do know that the the Umgeni did empty into the bay on at least some occasions during floods, but I don’t know if the situation was permanent. Leave a comment on the bottom of this post, or contact me if you know.
Certainly the Umgeni did flow into Durban Bay during the great floods of 1845 and 1856, but I believe that the true mouth of the river has always been near the Blue Lagoon.
I quote an extract of an email kindly sent me by Professor John Dunlevey (Geology) dated 27th April 2011 in which he wrote “the position of the mouth has been fairly static for quite a long time, but during each sea level ‘low’, the river cut quite a deep gorge out onto the continental shelf which has, of course, filled each time the sea level rose.
The gorge, filled with soft sediments, providing [sic] an ideal path for the next time the sea level dropped”.
To round out clarity about fluctuating sea levels, this should be read against an extract from the geology page on this site: ” During the most recent Ice Age about 18,000 years ago, sea levels reached about 120m below current levels, meaning that Durban, if it had been around, would have been about 15km inland”
And from another source that I am not sure I can identify but think was written by a retired Secretary of the Windsor Park Golf Course: “The estuary mouth appears to have moved between the bay and the sea until it was mechanically redirected by the city engineer in the early 1900s due to concerns of flooding, malaria and damage to reclamation works”
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