• 1971: Class Medal, B.Sc. Zoology 1st year course

  • 1974: UCT’s Purcell Prize for best dissertation on any Zoological subject

  • 1995: Best Paper: Queensland Hydrology Symposium, Australia

  • 1996: Silver Medal of the Southern African Society of Aquatic Scientists (for work on environmental flows)

  • 2003: National Women in Water Award from the South African Government, in the senior scientific research category (for work on environmental flows)

  • 2016: Gold Medal of the Southern African Society of Aquatic Scientists (for lifetime outstanding contribution to water science and management)

  • 2016: Recipient of WWF-SA’s Living Planet Award.

  • 2018: Elected member of the American Academy of Arts and Sciences (AAAS). Now serving on the Academy’s global project ‘Water security in a changing climate’.


Main research achievements

  • Lead developer of the Building Block Methodology (BBM), an holistic method for assessing the environmental flow requirements for regulated rivers. Development through application in real water-resource projects on the following southern African rivers: Lephalala, Berg, Olifants (W. Cape), Olifants (Transvaal), Letaba, Luvuvhu, Komati, Senqu (Lesotho), Mooi, Tugela, Mogalakwen, Koukoedoe, Sabie. In liaison with the SA national Department of Water Affairs and Forestry. 1991-1996. The development and use of the BBM in South African water-resource projects led directly to the inclusion of environmental protection (the ecological Reserve of water for ecosystem maintenance) in the country’s 1998 Water Act. This Act was globally seen as one of the most advanced in the world.

  • Co-developer of DRIFT, a scenario-based methodology for environmental flow assessments 1997-2002. DRIFT has a strong socio-economic component for predicting the impacts of changing rivers on rural subsistence users of river resources. It is commonly seen as the most structured, detailed and technically advanced of the environmental flow methodologies, and is now felt to be a step up from the holistic methods as it centres on ecosystem modelling to predict river and social change linked to water management proposals. It is increasingly being applied in developing countries in Africa and Asia. Endorsed by the World Bank, IUCN, FAO, IWMI, UNDP as international good practice. Approved by the Permanent Court of Arbitration in The Hague as “an appropriate tool for estimating potential change in the downstream environment” in tranboundary conflicts of the magnitude and complexity of the one under their consideration.