“An estuary is a partially or fully enclosed body of watera) which is open to the sea permanently or periodically; b) within which the sea water can be diluted, to an extent that is measurable, with freshwater drained from inland” (National Water Act, 1998). Estuaries are ecologically important because they are habitats for birds, fish and plants and they are valuable because they provide human beings with food (fish) and recreational pleasure in the form of unique views, bird watching and opportunities for swimming and boating. It is in this context that they may be said to provide economic goods and services for current and future generations. The provision of these services is dependent on the inflow of freshwater into estuaries. The problem with estuarine freshwater demand is that estuaries are the ‘last in line’, literally and perhaps in the typical prioritisation of human wants by government. Clearly it is imperative that the value of freshwater inflows into estuaries be determined and these values incorporated into catchment management decision making. South African estuaries have in the past mainly been managed on a piecemeal basissometimes in the interest of fishermen, sometimes property development owners and sometimes other local interest groups. This situation changed with the National Water Act of 1998. One of its objectives was to address the mismanagement and inadequate research about water inflow impacts on estuaries (Allanson and Baird, 1999). The global warming phenomenon is going to negatively affect estuaries and put more pressure on the availability of freshwater inflows into estuaries, as well as the availability of drinking water. The majority of South African estuaries are temporally open/closed and experiencing reduced functioning due to reductions of freshwater inflow to them. Given the overwhelming evidence available on the significance of freshwater inflow to estuary functionality, it is clear that an important component of catchment management is the allocation of river water into estuaries. Economic guidance comes in the form of comparisons of value. There are seven estuaries for which values were generated, the Heuningnes, Kleinmond, Klein, Palmiet, Cefane, Kwelera and Haga- Haga. All of the seven estuaries fall in areas characterized by warm temperate climates and low rainfall levels. Estuary services, like many other environmental services, are not traded in the markets. For this reason, in order to estimate their value, reference must be made to proxy markets, and methods of valuation have to be employed that can use proxy market information - like the contingent valuation method (CVM), the travel cost method (TCM) and the hedonic pricing method (HPM). For the purpose of this research the CVM was preferred because it is best suited to including passive or nonuse values. The CVM estimated values are compared with other values generated using the TCM. The information required to make the CVs was gathered through surveys in at the seven selected estuaries from December 2005 to April 2006. From this information sample mean and median Willingness to Pay (WTP) values for freshwater were calculated, socio economic profiles were generated, the importance that respondents attached to various activities in the estuary was deduced, and, Tobit and Ordinary Least Squares (OLS) statistics models were used to predict household WTP. The Total WTP (TWTP) for each estuary was obtained by multiplying the median WTP by the total number of households that use the estuary. The median WTP is preferred to the mean WTP because of a skewed bid distribution of WTP among the users. The value per m3 of freshwater was obtained by dividing the TWTP by the total forecast reduction in water inflows into the estuary.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:nmmu/vital:8994 |
| Date | January 2008 |
| Creators | Dikgang, Johane |
| Publisher | Nelson Mandela Metropolitan University, Faculty of Business and Economic Sciences |
| Source Sets | South African National ETD Portal |
| Language | English |
| Detected Language | English |
| Type | Thesis, Masters, MCom |
| Format | xxiii, 294 leaves, pdf |
| Rights | Nelson Mandela Metropolitan University |
Page generated in 0.0038 seconds