1. Sudwala Caves and Rainforest under Threat!

The Sudwala Caves and Rainforest are situated approx. 35km west of Nelspruit, Mpumalanga province, South Africa. The cave has a rich history, and is thought to have been used by man perhaps for many thousands of years. Stalagmites, stalactites and flowstone formations bear testimony to the dance these huge caverns have had with water. Awed to silence by the magnitude of this natural wonder, a visitor can hear nothing but the squeal of bats, and the drip, drip, drip of water – No More…

2. Drying up of Sudwala Caves – steps for investigating the possible causes

The claim by Geasphere that the Sudwala Caves and Sudwala Rain Forest (Natural Heritage Site #167) are drying up and field visit on the 12th July 2005, by representatives of the Department of Water Affairs a& Forestry, SAPPI and Geasphere, refers.

3. Sudwala Caves and Rainforest Drying Out

Letter to interested and affected parties inquiring about the research progress....

1. Sudwala Caves & Rainforest under Threat

Philip Owen, GEASPHERE
June 2005

The Sudwala Caves and Rainforest are situated approx. 35km west of Nelspruit, Mpumalanga province, South Africa. The cave has a rich history, and is thought to have been used by man perhaps for many thousands of years. Stalagmites, stalactites and flowstone formations bear testimony to the dance these huge caverns have had with water. Awed to silence by the magnitude of this natural wonder, a visitor can hear nothing but the squeal of bats, and the drip, drip, drip of water – no more…  

The Sudwala Rainforest grows at the base of a unique geological formation which manifests in a gigantic cliff face close to the Caves, clearly visible from the R539 (on the left as you pass Sudwala on route to the town of Sabie). Since the formation of the cliff face and certainly for as long as local people can recall, a ridge of fountains has been providing water that falls from the top of this cliff. The mist spray experienced at the bottom of the cliff and resulting lush vegetation has led to its name – The Sudwala Rainforest. The Rainforest has been declared National Heritage Site #167. Due to its sensitive nature it is not open to visitors, except for the occasional research or management survey.

During the late 1980’s a section of grassland on the plateau behind the rainforest cliff was planted to timber by Pine Valley Timbers (since acquired by Sappi). It was an obviously insensitive and badly thought through decision to use such a sensitive site for establishing a plantation considering the likely negative impact it was bound to have, of drying up the rainforest and cave systems.  

As should have been anticipated, these now mature plantations are exerting unsustainable pressure on the water resource, and compounded by the drought conditions is leading to the complete drying out of the unique rainforest and cave eco-systems. 

The Sudwala Cave has become extremely and unusually dry – even the fair late summer rains had failed to percolate through the deep cave system. A wet cave is a live cave. It grows and has structural integrity. A dry cave is a dead cave. Through this threat to the structural integrity of the Sudwala Cave, local tourism operations could be jeopardized. 

As the only change in the local catchment area has been the establishment of industrial timber plantations, and noting the well researched information on water use by evergreen deep rooting timber trees, we very strongly urge Sappi to remove all the trees that could have a potential impact, and to ensure that the area is restored to its natural grassland state. Interested and affected parties have indicated they could be willing to raise funds necessary to purchase the land in question from Sappi, should this become necessary.

Both the Sudwala Rainforest heritage site and the adjoining Sudwala caves deserve a caring and conserving attitude from Sappi when decisions are taken about the future treatment of this ecologically critical piece of land.

Philip Owen
GeaSphere

Sappi's  Position:
(As put to us by Divisional Environmental Manager - Dr. David Everard)

Rainforest:
Sappi’s position with respect to the rainforest is that we do not believe our plantations are having a significant effect on the water that trickles over the cliff into the forest.  This water is predominantly surface or subsurface flow and is fed by rain falling onto the catchment above the cliffs.  This area is not planted and is maintained as a grassland.  Our plantations are on the other side of a watershed and thus could impact on the water flowing in the other direction.  These trees are all legally planted and have been maintained at a cost and, therefore, are of significant economic value to Sappi.  We, therefore, do not feel there is rigorous case for us to harvest these trees early or remove them.  We have not been supplied by any independent scientific evidence that the trees are having a significant impact on the rainforest.  Until more information is provided we do not feel we have much to discuss on this issue.

Caves:
At this stage the only indication we have that there is a problem is from statements that the caves appear to be drying out. These statements are untested, unsubstantiated and based on impressions. For us to respond and discuss the issue of removing large areas of trees, with enormous cost implications, we would need far more rigorous evidence that our trees are the problem and that we are not just seeing the effects of a dry season.  Again we do not feel we have anything of substance to discuss with you and your legal council.  Our trees are legal, meet the requirements of the stream delineation procedures and are managed to sound (ISO 14001 and FSC) environmental standards.

2. Drying Up Of Sudwala Caves – steps for investigating the possible causes

The claim by Geasphere that the Sudwala Caves and Sudwala Rain Forest (Natural Heritage Site #167) are drying up and field visit on the 12th July 2005, by representatives of the Department of Water Affairs a& Forestry, SAPPI and Geasphere, refers.

We wish to raise the following issues with respect to the Sappi Proposed Expansion Draft EIR.
It is our contention that the impacts associated with ITPs - Industrial Timber Plantations - have not yet been comprehensively quantified. It is therefore not possible to make informed decisions regarding the ‘costs and benefits’ of expanding the mill at Ngodwana, that will lead to the further entrenchment of the industrial timber plantation model.

To establish whether the claim that the caves are drying up is valid, the following steps are suggested: -

1. Measure the humidity in the caves to establish the natural variations in water entering the cave.  Depending on the costs of such and apparatus two could be installed, i.e. one deeper and outside the influence of the tourists (base line) and one in an area frequently visited by tourist.
2. An adapted rain guage to measure the drops falling from the roof (most appropriate place still to be established).
3. Possibly a small measuring weir (V-notch) to measure the flow from a stalagmite (existing small dam at the foot of this stalagmite).
4. Determine the geographical co-ordinates at two to three points in the cave in order to geo-reference the map of the cave.

Measures to be taken outside the cave and the rain forest (natural heritage site): -

1. Map the geology at a scale of 1: 50 000 (the Council of Geoscience’s field maps to be obtained).  It is important to map any occurrences of dolerite as well - all efforts should be made to differentiate between different dolomitic lithologies.
2. Overlay geology map and cave map and decide on three to five drilling sites.  The aim is to determine the direction of groundwater flow and the depth to the water table.
3. At least one borehole should be drilled on the hill above the Rain Forest, e.g. between the edge of the cliff and the alleged offending stand of pine trees.  The aim is to determine the permeability and porosity of the shales that underlay the plantations (use down-hole geophysics).
4. Execute a hydro-census in the area surrounding the caves and underlain by dolomites of the Chuniespoort Group, to determine the volumes of groundwater being abstracted for whatever purpose.
5. Pinpoint any springs (wet and dry) in an area of 10km around the caves - special emphasis to be placed on ‘upstream’ springs (these must be classified according to the Standard Geosite Descriptors).

Steps #4, 5 & 6 must be completed before the borehole sites can be chosen and nay drilling commences.

The aim of all these actions is to determine the potential sources of the water entering the caves and potential flow paths.  Boreholes help will determine the groundwater potential of the dolomite and enable the monitoring of water levels, which in turm help determine recharge, and the hydro-census could indicate potential impatcs due to large-scale groundwater abstractions from the dolomitic aquifer.  Dolerite dykes and/or strongly developed fracture and/or joints could could act as preferential subsurface flow paths but could be fed by surface water, i.e. small streams fed by springs.  Determining the positions of springs, their flow regimes and flow paths could help resolve the cause - should the source of water be surface water.

The appropriateness of using rainfall station number xxx and the value of the flow gauging at station X2H014, needs to be evaluated.

Ernst Bertram
Assistant Director: Groundwater Information
15 July 2005

Sudwala Caves and Rainforest Drying Out

Letter to interested and affected parties inquiring about the progress with research.
27 August, 2004

Dear All
It has been almost two years since a formal investigation regarding the impact exerted by industrial timber plantations on groundwater was initiated. One aim of this investigation is to establish whether the timber plantations planted in the grassland above the cave / rainforest ecosystem is responsible in any way for the worsening drying condition being experienced in the cave during the past few years. For the first time – measures are being implemented by caves management to control dust – this was never necessary in the past.

We are still firmly of the opinion that the newly established (15 years) and maturing plantation above the cave system must be responsible – there have been no other changes in the catchment. Granted – we are experiencing more severe fluctuations in weather patterns – more severe dry and wet cycles – this compounded by the evergreen industrial timber plantation may just be too much for the system to tolerate.

Is there any preliminary findings in the DWAF investigation at this stage that can collaborate the statement above? If not, then I suggest the ‘Precautionary Principle’ should be adopted and the trees harvested as soon as possible and the land managed to rehabilitate the original grassland vegetation.

There is three plantation compartments in particular which is closest to the cave system and on its first rotation – so it is likely that some roots and bulbs / seeds of the original grassland vegetation might have survived the monoculture conditions. The compartments can clearly be seen on Google Earth – go to ‘Sudwala Caves’ or input the following coordinates – which will take you to the site of the dried up little fountain above the rainforest cliff. (25° 21’ 58,60” S 30° 42’ 16.76” E). There is one compartment to the north of this point and two compartments to the west. It amounts to approx. 50hectares – ideally and perhaps more timber should be extracted.

Please don’t hesitate to contact me with comments or advice.

Regards
Philip Owen
Geasphere