Restoring wetlands on a limited budget: The evolution of engineered interventions

Authors:
Fareed Nagdi

Publication Date:
2019

Abstract/Summary:
South Africa’s Working for Wetlands programme was established in 2000 through Expanded Public Works funding with the aim of restoring wetlands in a manner that maximizes employment creation, develops small enterprises, and transfers relevant and marketable skills to local communities. Balancing between the ecological and social outcomes of wetland restoration presented challenges in terms of the performance triangle of cost, time, and quality of constructed engineered interventions. The use of small, inexperienced contractors and labour drawn from local communities to work in often difficult wetland conditions and at isolated locations compounded the problem. The scale of degradation and the nature of the wetland systems requires a range of “soft” and “hard” interventions to be designed and constructed, and these range from the re-vegetation of mildly eroded soils to complex concrete weir structures that protect bed profiles of large wetland systems. Over time, the engineering budget has been declining, yet the pressure to improve efficiency and deliver more with less has been mounting. This has pushed the boundaries of innovation for the engineering team in terms of more cost-effective materials and cost-efficient designs. New design and construction principles, and more tolerant risk assessment criteria, sometimes going beyond the conventional approaches to engineering design have been developed. This paper presents the history, with examples, of how the engineering component of wetland restoration in South Africa has evolved. These engineering experiences have shaped the way wetland restoration planning and implementation are conducted in the country and may be applicable outside South Africa.  

Resource Type:
Audio/Video, Conference Presentation, SER2019

Pre-approved for CECs under SER's CERP program

Source:
Society for Ecological Restoration