The Umdloti River is relatively small but very important system that is located northeast of central Durban. This river flows pass the coastal town of Verulam and finally into an open/closed estuary, the La Mercy estuary. This fluvial system has a concrete gravity dam that is built in the upper reaches, the Hazelmere Dam, which supplies water to the north local council and surrounding districts under the supervision of Umgeni Water. The river is characterized by human activities, especially urbanisation and industrialization in the middle reaches and intensive agriculture (vegetables, sugar cane and banana plantations) along the catchment. The influence of anthropogenic factors within this catchment results from the dam construction, informal settlements, both commercial and subsistence agriculture, intensive industrial activity, accelerated urban developments, and recreational uses. Consequently there has been considerable concern regarding the impacts of these factors together with natural influences on the water quality and health status of this fluvial system. In this study water samples were taken and analysed for the following variables: nitrites; nitrates; ammonia; pH; Escherichia coli; sulphate; phosphate; total dissolved solids; chemical oxygen demand; biological oxygen demand; calcium and magnesium. The results indicate that the middle and the lower reaches of the Umdloti River are most impacted. Further, results from a questionnaire survey indicate that natural and human induced impacts have impacted negatively on the health status of the Umdloti River. The questionnaire survey also revealed that respondents benefited positively from the construction of the dam whilst the expropriation of land for the construction of the dam itself created much resentment to the prior land owners. The water quality data and the questionnaire analysis indicate overall natural and human induced impacts have had negative effects on the Umdloti River and the La Mercy estuary. It is necessary that local municipal authorities introduce corrective catchment management practices (outlined in the final chapter of the study) to enhance the water quality and health status of the river. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2009.

The health and life expectancy of populations in developing countries is largely determined by the availability of good quality drinking water. Boreholes and springs generally provide water of better microbiological and physical quality than surface water sources, however, they may cause health and aesthetic problems due to chemical constituents dissolved out of the host rock. As part of a pilot study to assess the health-related quality of community water supplies, samples were taken from two Quaternary catchment areas in KwaZulu-Natal. The Umkomazi catchment area is located inland from Amanzimtoti, while the Umfolozi catchment area is located north-east of Ulundi. The geology in these areas is significantly different. The Umkomazi area is predominantly underlain by basement rocks of the Natal Structural and Metamorphic Province, while the Umfolozi area is underlain by sedimentary rocks of the Karoo Supergroup. Geographical information systems (GIS) were used to examine the influence of lithology, rainfall and landuse activities on groundwater quality. Major ion analysis of groundwater samples from the Umkomazi area revealed a linear relationship between borehole and spring concentrations. Dwyka Tillite was found to produce water with the highest concentrations of major ions, while Karoo dolerite produced water with the lowest concentrations of major ions. Samples from basement rocks and Natal Group contained intermediate concentrations of major ions. In the Umfolozi area Karoo dolerite samples showed the lowest concentrations of major ions, while the Vryheid Formation and Dwyka Tillite produced the highest borehole and spring concentrations, respectively. High salinity levels in sedimentary rocks may be due to marine influence during deposition. Piper diagrams show relative enrichment of major cations and anions and Stiff diagrams showed characteristic patterns. Fluoride is associated with siliceous basement rocks and related to calcium concentrations through the solubility of calcium fluoride. The trace metals, manganese, iron and zinc were found to cause significant aesthetic problems and possibly health problems in sensitive individuals. These constituents are derived from weathering of bedrock and possibly from the corrosion of metal pipes. There is an inverse relationship between mean annual rainfall (MAR) and electrical conductivity (EC), except near the coast where windblown salinity increases with rainfall. Nitrate, ammonium and E. Coli contamination are linked to landuse activities such as occurrence of human and animal excreta near the water source and the proximity of pit latrines. It is recommended that rural communities be educated about the nature and importance of groundwater quality. / Thesis (M.Sc.)-University of Natal, Durban, 1998.

Waste water discharge into a temporary open/closed estuary (TOCE) system introduces two main concerns namely (1) the effects on the water balance of the system (quantity) and (2) the effects on the nutrient dynamics (water quality). Changes to mouth breaching patterns can severely impact the hydrological and ecological functioning of TOCEs, while excessive nutrient loading can lead to eutrophic conditions and algal blooms. Algal blooms occur when residence times during closed mouth conditions exceed the time scale for growth of the microalgal community. The aim of this study was to formulate a model in order to predict eutrophication events using the Mhlanga Estuary as a case study. The Mhlanga Estuary is situated approximately 19 km northeast of Durban and has a small catchment «100km2 ). The Phoenix and Mhlanga waste water treatment works (WWTW) collectively discharge approximately 20MI of treated effluent into the Mhlanga River per day. A simple daily-time-step water balance model was selected to model the hydrodynamics of the system. The model included various inputs and outputs of the system, residence time, storage, breaching water levels and time for mouth closure to occur. The result of the water balance model was a daily prediction of the mouth state and volume, and an indication of the breaching frequency. Observed mouth state data and measured water levels were used to test the model. In order to predict eutrophication events and trends at the Mhlanga Estuary, it was required that the conditions at which this would occur be investigated. This included the collection of samples (physico-chemical and chlorophyll-a) on a weekly basis for three months, a period that included three breaching events. Due to the complexity required in developing a nutrient dynamics model, a simpler approach was selected. The grey water index (GWI) was formulated in order to account for nutrient loadings into the estuary. WWTW discharge data were provided by eThekwini Municipality Water and Sanitation (EMWS). Initial results showed that under ideal conditions, an algal bloom would occur approximately fourteen days following re-closure of the Mhlanga mouth. The eutrophication index (E j ) was then formulated to account for both residence time and nutrient concentrations. The Ej at which eutrophic conditions can be expected was found to be about 50 %. It is important to note that this value for Ej is expected to be site specific and only accounts for the Mhlanga Estuary, but the concept can be generalized to other similar estuaries. Water levels simulated using the water balance model and observed mouth state data produced similar levels to those measured by DWAF. Following simulations of different flow scenarios (75% and 150% increase in WWTW discharges), it was found that an increase in capping flows resulted in more frequent breaching events and longer open mouth conditions. The risk of eutrophic conditions also increased with an increase in WWTW capping flows. Algal blooms are predicted to continue despite more frequent breaching events induced by an increase in capping flows. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, 2007.

Introduction Lake Mzingazi is the only suitable source of domestic water supply for the Richards Bay community. Rapid industrialisation in the city of uMhlathuze, accompanied by an influx of people, has resulted in informal settlement occurring around the lake. The uncontrolled activities of this development threaten to pollute the water source. Previous studies in1979 conducted by Council of Scientific & Industrial Research indicated that Lake Mzingazi water was still within acceptable limits in terms of the Department of Water Affairs & Forestry guidelines. The lake water quality was that of a Class I water resource, which is excellent for domestic use. Pollution of the lake can result from diffuse sources of pollution due to settlement of communities around it. Water purification costs could escalate thus forcing an increase in water tariffs. If pollution resulted in the lake being unable to be utilized, the Richards Bay community will be seriously affected, as it would necessitate the importing of water from distant regions. Either way, the expense of acquiring water would increase. All living organisms rely on adequate water for their survival. Worse still are human beings for their water should not only be adequate but should be of good quality to prevent health risks and even death. It is in view of these possibilities that the study was undertaken. Aim The aim of the study is to assess the extent of physical, chemical and biological pollution in Lake Mzingazi due to non-point sources and to recommend necessary protection measures that need to be implemented to prevent any negative health impact on surrounding communities. At present there are no restrictions and no protection of the lake from pollution except that no recreation is allowed into the lake at present. Methods Several objectives were set in order to focus on specific issues. One of the objectives was to inform the communities around the lake about the study. Sampling of the lake water was conducted monthly from June to November 2006 (using a boat). Pictures of areas around the lake were also taken for further analysis. At each sampling run, 36 samples were taken and delivered to a laboratory accredited by the South African National Accreditation Standards for analyses. Six sampling runs were completed. Secondary data for the period of 1998 to 2005 were obtained from uMhlathuze Municipality in order to establish pollution trends and for comparison purposes with the Department of Water Affairs and Forestry guidelines. Results The findings of the study revealed that the quality of the lake water is still within acceptable limits when compared with the Department of Water Affairs & Forestry guidelines; however, informal settlement threatens the future of the lake by encroaching into the lake banks. Discussion There is definitely a risk of pollution to Lake Mzingazi as long as there are no pollution prevention plans in place. Recommendations All data should be stored in a centralized information system to avoid losing valuable information. The Water Services Authority must develop and maintain a water quality-monitoring programme that will capture all changes occurring in the lake. / Thesis (MMed.)-University of KwaZulu-Natal, Durban, 2009.

Water, a fundamental and irreplaceable resource, is an all-pervasive issue that underpins the social fabric of every society. Rapid population growth and expansion of human activities increases the amount of waste and pollution generated and many local authorities are encountering serious water pollution problems, often concentrated in the lower reaches of catchments and adjacent coastal areas. This problem is predominantly acute in urbanized catchment areas, where waste is concentrated into localized areas, and the authorities are constantly under pressure to provide adequate management and mitigation measures. The Palmiet River system, located in the northern fringe of the city of Durban and draining the highly industrialized Pinetown region in KwaZulu-Natal, South Africa, illustrates a system that has been altered due to human impacts, particularly in its headwaters where the industrial sites are located and, in the lower catchment where a densely populated informal settlement occurs. A range of chemical and biotic indicators were monitored seasonally and these confirm the influence of the aforementioned human impacts on the quality of the Palmiet River system. Results from the present study were compared with studies conducted over a period of two decades and clearly demonstrate a pattern of increasing pollution loads for the upper and lower parts of the catchment. This study confirms that the Palmiet River is severely degraded in its lower reaches whilst the middle reaches of the catchment where a nature reserve is located is still in a fairly pristine condition. Additionally, the Palmiet River issues discussed in this thesis have direct impacts on the estuarine and adjacent marine ecosystems. / Thesis (M.A.)-University of KwaZulu-Natal, Durban,2005.

This dissertation focussed on the Mvoti River system in KwaZulu-Natal, an important resource for the numerous towns and villages along its course. Catchment activities are varied with agriculture being the predominant activity, and industrial activities common in the lower catchment. The Mvoti River is intensively utilized, especially in its lower reaches, to the extent that it is referred to as a ‘working river’. Modifications of the chemical and physical characteristics of the system, and consequently the biological characteristics, have led to degradation of the system such that the functioning of the lower river has deteriorated in comparison to that of its pre-disturbance condition. There are three main aspects of the Mvoti system around which this dissertation is based, namely, water quality, geochemistry, and conservation of the system. The results of the water quality survey of the estuary revealed that the system is presently experiencing water which is of an inferior quality. Compared against the South African water quality standards, a majority of the parameters exceed acceptable limits and are likely to present negative impacts on aquatic health and potentially human health. Comparison of current results, and water quality data for the system dating back to 1964, revealed that this degradation is not new to the system, and the Mvoti Estuary has in fact been experiencing continued deterioration over the years. The second part of this study investigated heavy metal presence in the sediments of the lower system and elemental presence and distribution in the surface sediments of the middle and lower River respectively. Results indicated that even though selected heavy metals are present, they are of concentrations lower than those of two other South African and two other international systems they were compared with. Enrichment and contamination assessments reveal that contaminants are in all probability present as a result of anthropogenic sources. However, distribution patterns which show highest levels just after effluent disposal sites suggest that the contamination is presumably human-induced and, the predominance of larger grained sediments that do not have high adsorption capacities, suggest that contaminants are readily remobilized into the water column. The final part of this research investigates other environmental problems, and causes, both natural and anthropogenic, experienced by the estuary system. These stresses include poor water quality, reduced water quantity, sedimentation, alien vegetation invasions and loss of biodiversity. Strategies to address these issues are proposed, with the intention of improving the condition of the estuary. This is an attempt at ecological restoration, to restore the estuary to a condition as close to as possible, to its pre-disturbance condition. These strategies include controlling abstraction and discharge, eradicating alien vegetation, controlling sandmining, and improving the overall quality of the system. Also proposed is an estuary management plan (EMP) for the Mvoti system, as there is currently no plan of such a nature in place. The EMP will aid restoration attempts, increase public awareness, and via post-project monitoring and evaluation ensure the success and sustainability of any future projects. Significantly, the adoption of an EMP will be a major step towards the rehabilitation, conservation and protection of this already degraded system. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2010.

This study represents an integrated and holistic assessment of the eziMbokodweni Estuary’s water and sediment quality. The estuary was once relatively un-impacted but now flows through a highly anthropogenically-modified catchment, comprising industrial and residential developments (formal and informal), and the eziMbokodweni Wastewater Treatment Works, furthermore the floodplain has been completely transformed to accommodate the Amanzimtoti golf course. Flow from the highly degraded Isipingo River and Estuary is occasionally diverted into the eziMbokodweni and the Southern Sewage Works Outfall, one of the largest deep sea sewage outfalls in the eThekwini Municipality, is located at sea, approximately 1.5 km south of the estuary mouth. Estuarine health can be studied on various fronts, in this study, the following variables were monitored in the water and sediment columns, seasonally for spring and neap tides: heavy metals, nutrients, bacteria and selected physico-chemical parameters. The results demonstrated that the eziMbokodweni catchment was a major contributor of heavy metals and nutrients to the estuarine system. The quantity of the majority of heavy metals and nutrients transported by the river at the upper estuary exceeded the amount exported to sea at the estuary mouth-nearshore interface, resulting in the estuary accruing large quantities of material seasonality. It was noted that the nearshore waters are enriched, as a variety of heavy metals and nutrients entered the estuary mouth during flood tide episodes. A range of heavy metals were detected within the sediment profiles obtained from the estuary, with fine to medium grained sediment exhibiting greater heavy metal content, in some cases, multi-fold higher than that detected in medium to coarse grained sediment. Geochemical indices were employed to ascertain the extent to which these metals constituted a pollution threat to the environment. The contamination factor calculated for all sediment layers and sampling sites implied low contamination. The enrichment factor calculated for the majority of heavy metals alluded to natural causes while some heavy metals exhibited significant to extremely high levels of enrichment thus implicating anthropogenic causes as likely sources of these heavy metals. The degree of contamination of the estuary was classified as low. Overall, the heavy metal and nutrient content detected in the sediments were low as compared to the large quantities detected from the budget. This indicates that natural mechanisms exist which facilitate the utilization or removal of these heavy metals and nutrients from the estuary. It is proposed that the most significant manner by which these heavy metals and nutrients are eliminated from the estuary is through episodic flood events that scour and strip fine grained sediment from the estuary bed. The pH assessment of the estuary revealed that this environment was slightly basic through most of the year with mildly acidic conditions noted during winter. The average Dissolved Oxygen levels were within acceptable levels, with the exception of winter when levels were very close to hypoxic conditions. The average Total Dissolved Solid content indicated that the estuary was compliant with the target water quality range for domestic use on selected seasonal-tidal cycles, and the average Electrical Conductivity levels were compliant with the ideal target water quality range for aquatic ecosystems and domestic use as per the South African water quality guidelines (DWAF, 1996a-e). A salinity gradient was evident in the estuary, as salinity levels decreased with distance from the estuary mouth. The saline nature of the lower estuary provided for the flocculation of material, which was alarming as large quantities of heavy metals and nutrients were detected in the estuary. The lower estuary is therefore susceptible to contamination due to the salinity regime and the dominance of fine grained sediment. The demand for oxygen in the estuary was high during summer, autumn and spring, and within acceptable levels for natural waters during winter. Extremely high levels of Chemical Oxygen Demand were recorded in the estuary which provides prime growth and survival opportunities for bacteria. This correlated with the results from microbiological investigations as high levels of bacteria were noted within the estuary, in both the sediment and water columns. The detected quantities of Total Coliforms, Faecal Coliforms and Escherichia Coliforms exceeded the target water quality thresholds for domestic and full contact recreational use. While at selected sites, the recorded Faecal Coliforms and Escherichia Coliforms levels were deemed compliant for intermediate contact recreational use. However, these sites were not compliant throughout the sampling period. Overall, the upper and mid-estuary exhibited greater counts of bacteria, in both the sediment and water column, than the estuary mouth and was attributed to factors such as flushing, sediment particle size, salinity and the ‘dilution effect’. Furthermore, the sediment of the eziMbokodweni Estuary is serving as a reservoir for bacteria. A number of options have been proposed to improve the degraded state of the eziMbokodweni Estuary and are ultimately aimed at curbing the anthropogenic input of these contaminants. The insight gained from this study provides the database from which more integrated and holistic estuarine management strategies can stem, that are applicable not just to the eziMbokodweni Estuary but estuaries in general. / M.Sc. University of KwaZulu-Natal, Durban 2013.

Since the establishment of a democratic South Africa in 1994, a number of rural water supply schemes have been implemented. A specific aim of these schemes is to improve the health of the population. The underlying assumption is that a supply of reticulated water will improve the quality of water used by the community, reduce the exposure of the community to contaminated water supplies, and reduce water related diseases, in particular diarrhoea. This research thesis focuses on two rural water supply schemes in KwaZulu-Natal: Mpolweni and Vulindlela, both being developed by Umgeni Water, the regional water utility. These communities depended variously on rivers, rain harvesting, and springs for their water supply. For sanitation, the majority of people used unimproved pit latrines. This research thesis is based on information gathered from the communities prior to the installation of the water supply schemes. It focuses on the linkage between water supply and health by examining diarrhoeal morbidity as a measurable disease outcome and by identifying possible pathways to the prevalence of diarrhoea. Questionnaire and observational surveys were undertaken of 181 households in Mpolweni and 100 households in Vulindlela. From these surveys, the prevalence of diarrhoea in Vulindlela households was found to be 40.4% and in Mpolweni to be 49%. Children under the age of five years old are the most vulnerable, with 20.1% of children in Mpolweni and 21 .3% of children in Vulindlela reported as having had diarrhoea in the recall period prior to the surveys. The Mpolweni study considered eighty exposure variables, finding an association between diarrhoeal disease and sixteen of these variables (p value < 0.05). The Vulindlela study considered fifty-five exposure variables, of which eight were considered significant (p value < 0.05). In regard to water and diarrhoea: • no association was found between the prevalence of diarrhoea and the source of water in either Mpolweni or Vulindlela. • using water to wash nappies was associated with diarrhoeal disease in Vulindlela. However, it is postulated that it is the faecal contamination in the nappy, rather than the water, that is problematic. No association between water use and diarrhoea was established in Mpolweni. • poor disinfection of stored water supplies was associated with diarrhoeal disease in both Mpolweni and Vulindlela. In addition, the use of plastic storage containers to store water at the household provided additional risk in Mpolweni. However, once the reticulated system is installed, the communities are likely to continue to store water due to a distrust of the reliability of water supply. The above surveys form the baseline for additional studies currently being undertaken by Umgeni Water that are intended to measure the effectiveness of the water supply schemes on community health. However, from this thesis, it is concluded that many of the risk factors associated with diarrhoeal disease in both Vulindlela and Mpolweni will not directly be addressed by the introduction of the water supply schemes. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2000.

This study assessed the quality of the Umgeni River in Durban South Africa seasonally from March 2011 to January 2012, according to standard protocol. Water samples were collected from Inanda dam-U5, KrantzKloof Nature Reserve-U4, New Germany-U3, Reservoir Hills –U2 and River mouth – U1 areas of the Umgeni River. A two-step tangential flow filtration (TFF) process was setup for the concentration of viruses from water samples. Virus like particles (VLPs) was detected using electron microscopy. Canonical correspondence analysis (CCA) was used to statistically evaluate the data sets. All water samples had turbidity values which exceeded the South African water quality guideline value of 0.1 NTU for turbidity. Large seasonal variations in BOD5, COD and conductivity levels were observed. Chloride concentrations were extremely high at point U1 (19234 mg/ℓ) Cl during summer. Total heterotrophic bacterial (THB) population was highest at 13.67 x 106 cfu/100ml (U1 – summer). Enterococci (EC) concentrations were detected at points U1, U2, U3, and U4 during the autumn and spring period. pH, electrical conductivity, temperature, and turbidity positively correlated with the microbial communities, and were the key parameters responsible for water pollution according to CCA. Most water samples contained high populations of somatic (659 pfu/mℓ, U1 – summer) and F-RNA coliphages (550 pfu/mℓ, U2 – summer). VLPs were detected throughout all seasons, with point U1 (summer) having the highest population of 2086 VLP/mℓ. Several presumptive viruses including Adenoviridae, Picornaviridae, Poxviridae, and Reoviridae were detected based on their morphologies. Six cell culture lines were used to determine cytopathic effect (CPE) of the VLPs. VLP samples produced CPEs on the Vero, Hek 293, Hela and A549 cell lines. Integrated cell culture (ICC) - PCR confirmed the presence of infectious VLPs in the river water samples. Adenoviruses, Enteroviruses, rotaviruses and Hepatitis B viruses were detected and quantified in all water samples by nested PCR/RT-PCR and Real-Time PCR respectively, against positive control viruses. These results indicate the potential of viruses in the water samples especially from the lower catchment areas to infect the human hosts throughout the year. These observations have public health care implications and establish a need to monitor the viral population in addition to traditional water quality indicators. / Thesis (Ph.D.)-University of KwaZulu-Natal, Westville, 2013.

Unpaved forestry roads can significantly affect surface runoff and sediment production, with consequential impacts for stream water quality. The potential impact of road runoff on stream water quality is mitigated by the redistribution of runoff into the forest compartments through road drains. The objective of this study was to assess runoff and the associated nutrient loads from unpaved forest access roads, and to evaluate the effectiveness of road runoff redistribution onto the forest compartments. Unpaved road segments in Mondi Forest Plantation in Seele Estate, New Hanover, South Africa were instrumented for runoff measurement in response to natural rainfall. Two road segment classes were investigated for water quality from unbounded runoff plots: steep sloped road segments of road gradients of 9.5° and 7.5°, and gentle sloped road segments of road gradients of 1.6° and 2.0°. Water quality was also assessed by monitoring road runoff, and stream water quality was analysed for water quality parameters including; pH, Nitrates, Nitrites, Phosphates, Total dissolved Oxygen, Oxygen consumption, Ammonium and temperature upstream and downstream of the Estate. The effectiveness of road runoff redistribution into the forest compartments was evaluated through relating water distribution to tree breast height diameter. Two sets of road drains corresponding to the plots of different road gradients were selected as for runoff, and sampled, and corresponding plots or allotments were established to determine tree breast height diameter measurements. The results of the study revealed that, as might have been expected, runoff production increases with the increasing road gradient. The quality of road runoff water was lower than the stream water. There were no significant differences observed in nutrient levels upstream and downstream of the road stream crossings. The nutrient concentrations however, were higher upstream of the estate than downstream. Significant differences in tree breast height diameter were noted between plots of different road gradients. This suggested that the gradient determines the infiltration of redistributed runoff and hence the availability of the water that can be used by the trees within a compartment. The results of the study suggest that unpaved roads are important in the generation of nutrient loads. Much of the nutrient value is redistributed within the compartment itself rather than being transferred to the stream. This suggests that, provided that road runoff can be contained within the compartments, the potentially negative impact of road runoff can be mitigated and may enhance tree growth. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.