scholarly journals Technical note: An anomaly in pH data in South Africa’s national water quality monitoring database – implications for future use

Water SA ◽  
2018 ◽  
Vol 44 (4 October) ◽  
Author(s):  
Carla-Louise Ramjukadh ◽  
Michael Silberbauer ◽  
Susan Taljaard

The South African national water quality database (Water Management System) houses data records from several environmental monitoring programmes, including the National Chemical Monitoring Programme (NCMP). The NCMP comprises an extensive surface water quality monitoring programme, managed by the Department of Water and Sanitation (DWS). The purpose of this technical note is to alert users to a systematic anomaly recently observed in the pH dataset of the NCMP, reflected in an abrupt increase between pre- and post-1990 data records. Although the cause of the anomaly in pH could not be confirmed with high confidence, an inappropriate acid rinse procedure in pre-1990 analytical methods was identified as the most likely cause, based on available evidence. This was supported by the variation in relative sensitivity when comparing the effect on waters with different buffering capacities, i.e., water with low buffering capacity (represented by total alkalinity < 10 mg/L, as CaCO3) showing the largest anomaly, compared with waters of higher buffering capacity (represented by total alkalinity > 30 mg/L, as CaCO3) showing the smallest anomaly. Historical pH data records in the NCMP (i.e. pre-1990), therefore should be used with caution, especially in more weakly buffered systems. The possibility of reconstructing data using a correction factor derived from detailed statistical analyses of the post-1990 pH characteristics at selected sites is a possible solution that could be investigated in future. A key lesson learnt is the need to be diligent in capturing detailed meta-data on sampling procedures and analytical methods in datasets spanning several generations. Availability of such information is critical in order to provide users with a means of evaluating the suitability and comparability of data records in long-term datasets. The DWS includes such meta-data in the current version of the database, dating from about 1995 onwards.

1998 ◽  
Vol 38 (11) ◽  
pp. 141-148 ◽  
Author(s):  
P. Marjanovic ◽  
M. Miloradov

The new National water policy will change the way water quality is managed in South Africa. The paper considers the water policy and the repercussions it will have for water quality monitoring in South Africa. Using the systems approach the paper discusses an integrated water quality monitoring system for ambient water quality and point and non point sources of aquatic pollution. The proposed methodology makes possible continuos assessment of water quality in an efficient manner so as to support water quality management in South Africa.


Author(s):  
Marcio R. M. da Bessa ◽  
Antonio C. P. Brasil

To take better advantage of the water quality monitoring systems and modeling processes practices in Amazon reservoirs, this study carried out a strategic methodology to couple these two tools. As a result, Information Monitoring and a Modeling Cycle are presented in this paper. The authors integrate the well-known Processes of Simulation and Systems of Monitoring & Assessment practices and incorporated improvements realized by efforts over the past 15 years, that is, UN/ECE Task Force on Monitoring & Assessment, and National Water Quality Monitoring Council and Brazilian Reservoir (NWQMC/USA) monitoring programs.


2003 ◽  
Vol 48 (10) ◽  
pp. 97-102 ◽  
Author(s):  
T. Lepono ◽  
H.H. Du Preez ◽  
M. Thokoa

Water quality is of prime importance to Rand Water’s core business of ensuring a reliable supply of good quality drinking water to more than 10 million people. Rand Water has, therefore, implemented a water quality monitoring programme of the source water as well as the drinking water produced. The establishment of the Lesotho Highlands Water Transfer scheme necessitated the expansion of the monitoring programme. In 1996, Rand Water and Lesotho Highlands Development Authority (LHDA) signed an agreement to jointly develop an extensive water quality monitoring programme for the Lesotho Highlands Water Project (LHWP). Prior to this agreement, monitoring was mainly undertaken by consultants on behalf of LHDA in the main feeder rivers within the Katse Dam catchment (donor system). On the recipient system (Ash/Liebenbergsvlei), extensive physical and chemical monitoring was undertaken by Rand Water and Department of Water Affairs and Forestry (DWAF). Biological monitoring was however only carried out superficially prior to the release of water. Information gained from carrying out biological and chemical assessments clearly indicates that the water from LHWP has negatively impacted on the biological communities in the recipient system. The importance of detailed before and after biological and physio-chemical monitoring of both donor and recipient systems is emphasised.


1998 ◽  
Vol 38 (6) ◽  
pp. 201-208 ◽  
Author(s):  
D. J. Smith ◽  
S. Crymble

Increasing demand for limited water resources within the Midlands of England resulted in a lower quality river being considered for water supply in an area of high urban and rural population. A comprehensive water quality monitoring programme was undertaken on the river to compare its quality with other sources used for water supply. Concurrent with the monitoring programme a series of laboratory scale trials began to assess how the river water could be treated, and the costs involved. A major consideration was the need to provide treated water by the summer of 1997, which precluded a complete new water treatment process from being designed. The paper outlines the results from the monitoring programme, including some of the problem parameters such as pesticides at over 10 ug/l, and how some of the sources of these pollutants were identified. It also describes the treatment trials and explains how a water treatment process was developed which utilises disused gravel workings to provide bankside storage and a combination of powdered and granular activated carbon to remove organic pollutants.


2011 ◽  
Vol 45 (1) ◽  
pp. 19-28
Author(s):  
Rob Ragsdale ◽  
Eric Vowinkel ◽  
Dwayne Porter ◽  
Pixie Hamilton ◽  
Ru Morrison ◽  
...  

AbstractThe Integrated Ocean Observing System (IOOS®) Regional Associations and Interagency Partners hosted a water quality workshop in January 2010 to discuss issues of nutrient enrichment and dissolved oxygen depletion (hypoxia), harmful algal blooms (HABs), and beach water quality. In 2007, the National Water Quality Monitoring Council piloted demonstration projects as part of the National Water Quality Monitoring Network (Network) for U.S. Coastal Waters and their Tributaries in three IOOS Regional Associations, and these projects are ongoing. Examples of integrated science-based solutions to water quality issues of major concern from the IOOS regions and Network demonstration projects are explored in this article. These examples illustrate instances where management decisions have benefited from decision-support tools that make use of interoperable data. Gaps, challenges, and outcomes are identified, and a proposal is made for future work toward a multiregional water quality project for beach water quality.


2004 ◽  
Vol 38 (4) ◽  
pp. 163-166 ◽  
Author(s):  
Ian Spellerberg ◽  
Jonet Ward ◽  
Fiona Smith

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