Rains recharge St Lucia estuary system
Recent rains fell into catchments directly abutting the wetland park
WHILE last weekend’s rains, mostly limited to the coastal belt, did not significantly affect the upper catchments of the Mfolozi and Mkhuze rivers, they did have a positive impact on the St Lucia estuary system.
The rains fell into the catchments directly abutting the iSimangaliso Wetland Park, with Kosi Bay receiving 12.5mm; Manzengwenya, uMkhuze North 10.3mm; uMkhuze South 25mm; False Bay 70.2mm; Charters Creek 43.5mm; Mission Rocks 61.3mm, and St Lucia 70.5mm.
According to the iSimangaliso live monitoring system, during the 24 hours prior to Monday morning, the St Lucia estuary had risen by 10cm.
Before the rains, the Msunduze River level at Cotcane was reportedly below 0.95 metres above sea level (msl) and by Tuesday morning it had reached 1.098msl.
But by 8pm on Tuesday night, levels had risen to 1.245msl, exceeding the level which is required for iSimangaliso to breach the river at a point of its choosing, in line with the interim high court agreement in place until the matter is heard by the court next week.
‘iSimangaliso will give effect to the settlement agreement made an order of court according to its terms,’ said iSimangaliso CEO Andrew Zaloumis.
‘This requires iSimangaliso to breach the mouth at a point of its choosing when the Msunduze water levels reach 1.2msl at Cotcane and there is back-flooding of farmlands.
Breaching with current lake levels will have a negative impact on the Lake St Lucia system and could possibly delay the current work to remove dredge spoil’.
Water flows
A temporary bridge put in place across the Mfolozi River, for Cyclone Engineering contractors to move plant equipment to be used in the dredge spoil removal, was removed.
This allowed fresh Mfolozi River water to flow into the estuary which, it was reported on Tuesday afternoon, was entering the system at approximately one million litres per hour.
The bridge will be restored once the flow has subsided, to enable work to continue.
‘With food being the critical issue for animals, especially in the uMkhuze section of iSimangaliso, the localised rain has recharged some of the dry local pans.
‘This, together with water seepages and puddles, will allow game to move to areas where the grazing is less stressed as they are not bound to areas around the pumped watering holes.
‘Without more rain, however, the prognosis for winter is not good and this relief is expected to be short-lived,’ said Zaloumis.
