St. Lucia estuary mouth is closing!

 This pic was taken on Saturday 11  June 2022.  The St. Lucia estuary mouth is where three water sources meet. First is the Umfolozi River mouth. Next is the lake tidal link and the third is the Indian ocean. In the past. The Umfolozi and Mzundusi overflow were managed separately from the lake tidal link. The main reasoning behind this separation was the vast quantities of silt within the Umfolozi River flood waters. 

The 2017 GEF PROJECT ignored this silt factor,  and the scientists appointed by the iSimangaliso Wetland Park Authority ran a very effective public perception management strategy to endure that the public accepted their rather nasty proposal to link the Umfolozi River directly to the rest of the St. Lucia lake systems, in their efforts to get water into the St. Lucia lake systems.

The results are now evident as can be seen here. Silt has settled in nasty places and clogged up the inter-tidal flow paths  Mud, mud and more mud  now needed to be removed.  This is going to be difficult.

What ideas do you have that may help us solve this problem ?

Got an idea ?  One that may help solve the problem ! Send it to 4u2fish@info4u.co.za

 

The silt levels within the St. Lucia lake and estuary systems is  much worse than the IWPA is telling.  The tidal link between the lake and estuary systems is now a thing of the past, but we need this tidal channel to work so that the fish breeding and nursery grounds may become functional.  the St. Lucia lake  system used to sustain more than 60 percent of all fish breeding grounds in South Africa.  This is now not available to our fish stocks. thus is a rather nasty problem, and our marine fish stocks are suffering a very disturbing loss of juvenile recruitment , meaning that this is leading to a collapse of our coastal fish stocks.

what to do ?  everybody appears to be ignoring these losses of nursery grounds for our coastal marine fishes.

how will we bring this problem into the foreground of nature conservation and the management of our local  natural renewable resources ?

any help will be appreciated.   see our Facebook pages at facebook.com/4u2fish and leave a comment discussing your views on this nasty problem.

Silt from the Umfolozi River closes narrows and related mudflats

It is now June 2022, and the impacts of the GEF PRJECT (2017)  are being felt in the northern sections of Lake St. !uca, in the iSimangaliso Wetland park world heritage site. The assive  silt wall that forms the blockage cross the northern adges of the narrows is currentlybetween 2.5 and3  meters vertical above spring tide high water mark.

When the GEF PROJECT was implemented in early 2017 the contractors , who were paid by the IWPA, ( iSimangaliso Wetland Park Authority) connected the Umfolozi River directly to the southern sections of the St. Lucia estuary, ensuring that there was a flow path for the water from the Umfolozi River to flow directly in to the southern sections of lake St. Lucia at the northern edges of the estuary narrows. The mining spoil was deposited between the river flow path and the ocean. This mining spoil was flattened by big bulldozers and the excess was just pushed into the ocean.

This wall between the ocean and the river ensured that the river would not easily break open a channel to connect the river to the ocean. The proof off this statement is the physical height that the flood waters rose before actually opening the mouth on 14 April 2022 

So how did this big silt wall at the top end of the narrows grow so high ? 

Well this is he  start of the narrows as it flows from the lake systems into the estuary system. This is where the river water would join the lake water, slowing down to a sudden halt with slow swirling actions, dropping silt in the same location with each flood event. The silt deposits here were very significant. When the Umfolozi River floods, it carries huge volumes of silt. A fair volume of this silt ends up on the Umfolozi floodplains, but due to the activities of the GEF PROJECT the flood waters were not entirely attenuated within the Umfolozi Flats, so a fairly large volume of silt laden waters flowed in the GEF PROJECT prefered water flow paths, ensuring that the silt dropout zone remained static and geographically stable allowing the silt to settle and build up within the vast reed beds that have grown where there should be tidal water flows. 

This blockage grew and expanded  into a vast reed bed, which ensured that the next, and all subsequent flood event would use the same silt drop out zone, making the blockage a perminant part of the landscape. Smaller flood events soon failed to climb over this blockage, which ensured that the areas undervwater due to so called z#BACKFLOODING had all the fines and duper fines within the silt load drop out there where it is not welcome. One just needs to look at the dead mangroves along the estuary banks to see the nasty impacts of silt. The  fine silt prevents the mangrove roots from breathing, eventually killing the plant.

So each new flood event had to first nuid up to the top of this disturbingly big blockage before filing the lake further. Now once again the silt dropout zone would still be this well reeded blockage, making this blockage grow rather suppringy with each flood event. The last flood event which caused the Breach of the St. Lucia estuary mouth on 14 April 2022 left a considerable sit load ontop of this blockage. This is very evident and highly visible, coz the water levels in the northern sections of the lake are still not dropping. The silt loads in the system need to be explained  !

The estuary sceintists knew about  this issue of excessive silt but chose to ignore the silt issue altogether. This was a deliberate and intionio!!

!?nal decision .., many folks tried to raise the issue, but #UncleAndrew and his paid team also made sure that the public also ignored the silt issue, and gave the IWPA a MANDATE to push the GEF PROJECT s nthat it became a reality, and they physically connected the Umfolozi River directly to the St. Lucia lake systems, side stepping the natural filter systems in the Umfolozi River  flood plains and Monzi flats .

This was a very serious and drastic change to the silt loads introduced into the Lake St Lucia systems. Yhiscwas a never before sceintific experiment, and it has had some very nasty side impacts.  The changes to the waterflow patters of the lakes is really scary. What are we gonna do ? !!!

This means that the lake systems are no longer tidal,. As there is a very high sand bar / silt barrier between the lake systems and the esturine neater ways that connect the lake to the ocean.

Any ideas on your part ?

Leave a comment!

#Frankie2Socks for the #4u2fish Campaign