Heritage Cases

The Roodekrans weirs and culvert development project entails the construction of 4 weirs and the construction of a road culvert on the farm Roodekrans. The culvert will be constructed under the existing farm dirt road. The weirs and the culvert will be located along an unnamed tributary of the Crocodile River. The tributary is fed by a spring and is non-perennial. Previously the drainage channel to the east of the property was diverted, at the point where it crosses under the farm access dirt road, towards the existing dam on the property and both channels fed into the existing dam. As a result the eastern channel and surrounding wetland was mostly dewatered and alien vegetation became established along this section. The proposed development will divert the eastern channel back along its original course and it is also along this section of the channel that 3 of the weirs will be constructed. The proposed development will allow natural rehabilitation and recovery of the degraded wetland downstream of the access road. The weirs have been designed in a manner that will improve the current state of the tributary of the Crocodile River and thereby improve the current status of the Ecological Support Area of the Critical Biodiversity Area as identified under the Mpumalanga Biodiversity Sector Plan. One weir will be located up-stream of the road culvert and the other 3 will be located down-stream of the road culvert: - Road Culvert: An existing farm access road that crosses a drainage line will be upgraded to prevent the road from being washed away during rainfall events and to allow the stream to flow more freely. The upgrade will entail the installation of suitable culverts and an increase in the height of the road. The road will not be widened and will be upgraded within the current footprint. The road crossing the area below the small dam along the access road has caused dewatering of the channeled valley bottom wetland causing the invasion of the wetland by terrestrial species and weeds. The installation of the culverts under the road will aid in rehabilitating the downstream channel and wetland areas. Three pipe culverts, each with a diameter of 1 meter and approximately 8 meters in length will be installed under the road. Gabions will be placed along the embankments of the road to prevent the road from being eroded by stormwater. - Four Weirs: The weirs will be constructed to retain water and to provide water for cattle on the farm. Weir 1 will be located on the northern side of the road in an area classified as high sensitivity with wetland and drainage features. Weir 1 will be 7.75 meters in length and 6 meters in width. Weirs 2, 3 and 4 will be on the south side of the farm access road in an area classified as medium sensitivity wetlands in a degraded state (according to the ecological report). Weir 2 will be 8.8 meters in length and 7 meters in width. Weir 3 will be 9 meters long and 7 meters in width. Weir 4 will be 8.35 meters in length and 6 meters in width. The total surface areas and exact locations of each weir on the property are indicated in the table below. The weirs will be constructed using gabions and scour pools will be prepared using rock material on the down-stream side of the weirs which will aid in preventing erosion. Furthermore, graded cobbles and gravels will be used to make a smooth transition to the natural channel boundary. The weirs are anticipated to provide drinking water for livestock on the farm, while the larger dams will be utilized for trout fishing. The weirs trigger listed activities under the National Environmental Management Act (Act no 107 of 1998) however the upgrade of the existing road which entails the installation of a culvert does not trigger any listed activities under the NEMA as the upgrade will occur within the footprint of the existing dirt road.