Aspects of the motivation for voluntary disclosures: evidence from the publication of value added statements in an emerging economy

This paper investigates the motivation for the voluntary disclosure of financial information by companies in their annual financial statements, by examining aspects of the usefulness of the value added statement. The value added statement is published voluntarily with the annual financial statements and is currently experiencing high levels of publication in South Africa, which is evidently brought about by the high political costs and significant legitimacy threats that companies operating in South Africa are facing. It was found from the literature and from a survey among management that the value added statement was primarily aimed at the employees. Employees have also been regarded as users of financial information in the literature. However, a survey among trade unions in South Africa found that almost no use is made of the value added statement even though the unions make use of other financial information. This indicates that voluntary disclosures do not necessarily satisfy the information needs of their intended audience. The research also indicates that the trade unions might not use the value added statement because they suspect that the statement is being used to reduce political costs and legitimacy threats, and is therefore not reliable. This is a major shortcoming of voluntary disclosures

The value added statement: bastion of social reporting or dinosaur of financial reporting?

South Africa is at present experiencing the highest incidence of publication of the value added statement reported anywhere in the world to date. In addition research investigating the predictive ability of value added information has been conducted in the USA since 1990, even though the value added statement has not been published there. The research reported in this paper sets out to establish whether the value added statement is a disclosure worth considering by companies around the world, by investigating the South African experience with the value added statement. The social accounting theories of organisational legitimacy and political costs were found to be best suited to explain why the value added statement is published. Surveys among the companies publishing the value added statement indicated that management had the employees in mind when they published this information. However, a survey among users has indicated that very little use has been made of the value added statement. The main reason for this seems to be that the unregulated nature of the value added statement allows for inconsistencies in disclosures, which eventually caused users to suspect bias in the reports. The USA evidence that the information has additional predictive power is not confirmed by a South African study, and is complicated by the limited additional information contained in the value added statement. The South African experience with the value added statement does not make a convincing case for publication. Rather, it highlights the need for unbiased and verified social disclosures that will be useful to all the stakeholders of the company. In addition, it has implications for other voluntary social and environmental disclosures

Greywater: What can we do?

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Technical note: Measurement and expression of granular filter cleanliness

The problem of dirty filter media at water treatment plants, despite having good backwash systems, is a serious challenge that requires constant monitoring and maintenance. To aid the systematic analysis of filter media and the troubleshooting of problem filters, this paper firstly proposes a standard procedure for quantification of the specific deposit on filter media, including tentative guidelines for the interpretation of the results. Secondly, a standard procedure is proposed for the characterisation of the specific deposit, based on its volatility and its acid solubility. These fractions are helpful to trace the origin of excessively dirty filter media. Thirdly, the utility of the proposed procedures is demonstrated by the results of a South African treatment plant survey. This confirms some earlier observations that there often is a real problem with recalcitrant specific deposits that cannot be readily removed by backwashing, a fraction that correlates with the organic fraction in the specific deposit.Keywords: backwashing, specific deposit, filter media, filter cleanlines

A practical course on filter assessment for water treatment plant operators

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How to measure specific deposit washout and backwash efficiency of granular filters

Abstract Practical experience shows that water treatment filters develop problems over time due to the routine running of the filter, including backwashing. There are difficulties in maintaining filters in good condition, given the eutrophic state of many South African raw waters, high water temperatures and the development of difficult-to-remove biofilm as a result. Such difficulties are often related to deposits accumulated on the filter media and it is, therefore, expected that the backwash system should be good enough to ensure that the filter is kept clean in the long run. This paper deals with a fairly simple operational option to significantly improve backwash efficiency at treatment plants where air and water are used consecutively. The paper describes methods used and typical results obtained in the testing of the quantitative benefits of multiple wash cycles. Multiple washing shows great promise for improving backwash efficiency, with an average of an additional 40% to 50% of the solids that would have been washed out with a single wash, removed by a second wash. Furthermore, third and even fourth washes continue to remove additional dirt from the filter. Multiple washing, therefore, may be a useful tool for the effective rehabilitation of a filter, as well as for routine operation procedures

The use of filter media to determine filter cleanliness

Abstract It is general believed that a sand filter starts its life with new, perfectly clean media, which becomes gradually clogged with each filtration cycle, eventually getting to a point where either head loss or filtrate quality starts to deteriorate. At this point the backwash cycle is initiated and, through the combined action of air and water, returns the media to its original perfectly clean state. Reality, however, dictates otherwise. Many treatment plants visited a decade or more after commissioning are found to have unacceptably dirty filter sand and backwash systems incapable of returning the filter media to a desired state of cleanliness. In some cases, these problems are common ones encountered in filtration plants but many reasons for media deterioration remain elusive, falling outside of these common problems. The South African conditions of highly eutrophic surface waters at high temperatures, however, exacerbate the problems with dirty filter media. Such conditions often lead to the formation of biofilm in the filter media, which is shown to inhibit the effective backwashing of sand and carbon filters. A systematic investigation into filter media cleanliness was therefore started in 2002, ending in 2005, at the University of Johannesburg (the then Rand Afrikaans University). This involved media from eight South African Water Treatment Plants, varying between sand and sand-anthracite combinations and raw water types from eutrophic through turbid to low-turbidity waters. Five states of cleanliness and four fractions of specific deposit were identified relating to in situ washing, column washing, cylinder inversion and acid-immersion techniques. These were measured and the results compared to acceptable limits for specific deposit, as determined in previous studies, though expressed in kg/m3. These values were used to determine the state of the filters. In order to gain greater insight into the composition of the specific deposits stripped from the media, a four-point characterisation step was introduced for the resultant suspensions based on acid-solubility and volatility. Results showed that a reasonably effective backwash removed a median specific deposit of 0.89 kg/m3. Further washing in a laboratory column removed a median specific deposit of 1.34 kg/m3. Media subjected to a standardised cylinder inversion procedure removed a median specific deposit of 2.41 kg/m3. Immersion in a strong acid removed a median specific deposit of 35.2 kg/m3. The four-point characterisation step showed that the soluble-volatile fraction was consistently small in relation to the other fractions. The organic fraction was quite high at the RG treatment plant and the soluble- non-volatile fraction was particularly high at the BK treatment plan