Runde running out of water

their laundry in a similar pool that seems to be succumbing to the rampant and growing spectre of siltation in the mighty Runde River.
The river is sluggishly trying to retrace its course in Masvingo’s south-east Lowveld region.
Decades of incessant siltation have created a series of eye-catching ox-bow lakes that replicate along one of Zimbabwe’s biggest and most crucial river which feeds the populous and dry Chilonga communal lands in Chiredzi.
For centuries, Runde River has not only provided a lifeline to humans and their livestock on its tempestuous sojourn from Zvishavane district. It has also been the cardinal hinge sustaining a diversity of wildlife species and flora in the Gonarezhou National Park, where Runde joins Save River – close to the Mozambican border – before the latter completes the final lap into the Indian Ocean. The once mighty Runde River that sires the picturesque Chilonjo Cliffs and the spectacular Chipinda Pools in the Gonarezhou National Park, is slowly turning into a big shadow of its former self. It is battling under the weight of relentless siltation that does not only threaten the survival of families who have depended on the river for their agricultural wherewithal, but most critically the future of wildlife in one of the zones with arguably the highest concentration of wildlife in Zimbabwe.
Both terrestrial and aquatic wildlife species in the southeast Lowveld have their fate intertwined with Runde River which provides drinking water to approximately the highest number of wild animals in the vast Gonarezhou National Park that is slowly morphing into the Great Limpopo Transfrontier Park.
Though endowed with several other major rivers such as Mwenezi, Chiredzi and Tokwe that augment and increase the surface area of drinking water for wildlife. The southeast Lowveld region is gradually slipping down an environmental precipice owing to the inevitable demise of the Runde River.
Environmentalists and wildlife experts argue that the looming distortion of the Runde River regime to siltation will not only destroy habitats for aquatic creatures such as crocodiles and hippos but also lead to loss of some plant species that survive on Runde waters.
Parks and Wildlife Management Authority spokesperson Caroline Washaya Moyo said the threat posed to wildlife in the southeast Lowveld area and particularly in the Gonarezhou National Park by the continued siltation of Runde River was a cause for concern.
She pointed out that the death of Runde River would have earth-shattering environmental and ecological effects as the huge river was a critical fulcrum whose axis guaranteed the continued existence of various wildlife and plant species in the south east Lowveld.
“The siltation of the Runde River has negatively impacted on both the quality and quantity of water for local communities, companies, wildlife dependent on the river among other uses. The flow of the river is typical of the arid and semi-arid areas.
“The slow flow of the river causes it to deposit its load as it will have less energy thus siltation occurs. Silt has been observed to clog fish gills, smother eggs and destroy the aquatic habitat. Again siltation makes the river an unfriendly, unhealthy place for fish to swim and play,” said Ms Washaya Moyo. Hippos and crocodiles, among other aquatic animals such as fish domiciled in Runde River, have of late had to content with the growing and festering sore of siltation, a bane that threatens to swallow their entire habitat transforming it into a belt of sand.
The ghost of siltation in the Runde River is also partly blamed for the rapid shrinking and disappearance of wetlands across the Gonarezhou National Park that previously would have provided a reliable source of food for a variety of grazers in the vast wildlife reserve.
“Runde River is a backbone of both aquatic and terrestrial life in the Gonarezhou National Park. The same applies to the Save and Mwenezi rivers. The Runde supports major pans in the park, namely Tambohata and Machaniwa by backflow when in flood.
Aridification or drying up of the Runde River will affect a wide range of ecological processes, due to possible loss of important wetland habitats and reduced stream discharges. For instance, the river supports the highest population of hippopotamus in the park, a healthy population of crocodiles and diverse fish species. If the river dries, then aquatic life will be lost,” Ms Washaya Moyo noted. Ms Washaya Moyo said that the slow death of Runde River under the stranglehold of increasing siltation would engender the lives of large herbivores such as elephants that rely on Runde River for drinking water since the huge wildlife reserve is not equipped with artificial water drinking points for wildlife.
Ms Washaya Moyo said the other associated implications of siltation are related to changes in the flooding regime of the river, as a highly silted river is prone to flash floods, destroys natural wetlands and water pans by depositing silt. Research in the Gonarezhou National Park has shown that climate-change associated extreme events such as droughts and flooding have huge and negative implications on wildlife resources.
The studies have shown that during the 1991-92 severe drought there was a significant mortality of trees in the park, a situation that opened floodgates for erosion and subsequently siltation in rivers such as Runde.
She said: “More recently, more studies have also shown that hippopotamus populations have disappeared in the Mwenezi River and only remain in the Runde and Save Rivers and its associated pans.
The Frankfurt Zoological Society-bankrolled Gonarezhou National Park Conservation project says the fate of Runde River, in light of the threat posed by increasing siltation, was of paramount importance as the river was a lifeline for aquatic and terrestrial species in the south east Lowveld.
Mrs Elsabe van der Westhuizen who is a co-project leader at the Gonarezhou Conservation project says Runde River was key to the future of Gonarezhou National Park as it was the only river that flows through a major national park for its entire lower course.
“With special reference to the Gonarezhou – the Runde River obviously plays a vitally important role for the animals and vegetation of the park.
“It is the only major river in Zimbabwe that runs through the middle of a national park for any significant length and as such presents a unique opportunity to protect and conserve this important natural resource. However, as a downstream ‘user’ of the river, the Gonarezhou is entirely dependent on sound management of the river by upstream users,” she says.
She further claims that there was a lurking danger that Runde River might lose its perennially flowing river status by sliding into a seasonal river owing to the increasing siltation.
“If the Runde is to turn from a perennial to a seasonal river due to reduced flow it will have a major effect on the composition of the aquatic species, with the disappearance of species that are dependent on continuous flow and that can’t survive in isolated pools formed during the dry season. Furthermore, increased growth of algae due to the unnatural enrichment of the water by agricultural run-off and urban waste leads to reduced levels of oxygen and loss of habitat which directly impacts on species richness and composition,’ says Mrs van der Westhuizen.
There have also been calls for the formation of the Save/Runde catchment protection committee that will, among other things, manage the two major river systems.
It is vitally important that all stakeholders in the Lowveld support measures that more effectively monitor the quality and flow of the Runde.
“One should not lose sight sight of the fact that the Runde River joins up with the Save River, which crosses into Mozambique where it also serves numerous communities and wildlife areas. There are also issues of cross-border responsibilities in maintaining river quality and flow – and towards this end it might be necessary to instigate the formation of a Save/Runde catchment body along the lines of the Limpopo River Basin Commission (Limcom),” she added.
The problem of siltation in Runde River has also been further compounded by poor farming methods from communities especially those in settlements that were opened up in new areas that border major river systems in the southeast Lowveld and where communities live in areas adjacent to game reserves.
The widening scope of soil erosion into tributary rivers feeding into major rivers like Runde, that is partly caused by increased population pressure, coupled with poor farming methods in the Lowveld major rivers’ catchment areas will definitely continue to be a major impediment to averting an ecological disaster caused by siltation in the wildlife-rich zone.
Thus the survival of both diverse aquatic and terrestrial species in the south east Lowveld calls for sound environmental and ecological management that will save the Runde River from eventual suffocation under the weight of rampant siltation.