The most significant impact of Umgeni Water’s business is provision of water that does not impact negatively on consumer health over a lifetime of consumption. Water quality is managed through a rigorous management system which covers the entire operational area and includes carefully planned monitoring programmes, auditing, compliance reporting, water quality risk assessments – conducted using a catchment to consumer approach – and the implementation of Water Safety Plans.
Water quality monitoring programmes are reviewed annually for all Umgeni Water operational sites and sampling and analysis are undertaken in accordance with Umgeni Water’s ISO 9001 certified monitoring programme and SANAS 17025 accredited laboratory methods, respectively. An emergency response protocol which includes various alert level triggers has been developed and is active.
Water quality performance data, information and reports are disseminated to all stakeholders. Umgeni Water is committed to continue to provide support to municipalities to ensure that all systems can be progressively improved toward joint Blue Drop Certification.
Potable Water Quality Performance
Umgeni Water’s bulk Water Treatment Works and iLembe Rural Schemes are required to comply with South African National Standards SANS 241: 2011 which required quality to be evaluated and reported against four risk categories:
Acute Health 1 – Microbiological,
Overall, for the reporting period, Umgeni Water provided excellent drinking water quality to customers. The detailed potable water quality compliance per water treatment works is shown in Table 9.1 followed by explanation for variance areas and solutions to address these.
Table 8.1: 2013/2014 Potable Water Quality Compliance with SANS 241:2011 per Water Treatment Works (WTW)
|Water Treatment Works||Treated Volume Ml/d||Volume %||Acute Health 1 – Microbiological||Chemical Health||Operational||Aesthetic|
|iLembe small schemes and boreholes1||6||0.5%||97.98||99.25||83.85||94.61|
Key to classification of the performance of drinking water supply systems according to SANS 241: 2011:
Overall nine (9) major water treatment works complied with the SANS:241 excellent category for drinking water quality and one (1) Mvoti WTW complied with the good category.
One (1) water treatment works Maphephethwa did not comply with the operational water quality category. In addition the iLembe small schemes and boreholes did not comply with the operational water quality category.
Variance – Maphephethwa WTW experienced variance with operational parameter: 86.4% compliance (6.6% variance). iLembe Small Water Treatment Schemes and Boreholes: 85.9% compliance (7.1% variance).
Reason and Action Plan – Turbidity and aluminium non-compliances were the cause of the non-compliances.
The Maphephethwa WTW has operated above its design capacity for most of the year. Partial commissioning of the upgraded plant occurred in 2012/2013 and water quality problems are anticipated to be resolved following full commissioning of the plant in 2013/2014.
Progress is being made with a turnaround strategy to progressively improve all iLembe boreholes and schemes. Some of the small schemes will be upgraded and some will be replaced by the Maphumulo Bulk Water Scheme.
Figure 8.2: iLembe boreholes and small schemes potable water quality compliance (%).
Blue Drop Certification and Drinking Water Quality Management Excellence
Umgeni Water received nine Blue Drop certifications for drinking water quality management excellence, together with the relevant Water Services Authorities in 2012. Assessments are conducted every two years. In January 2014, the Department of Water and Sanitation (DWS) conducted a detailed blue drop assessment for all Umgeni Water systems, twenty-nine (29) in total, together with the relevant Water Services Authorities. The results of the assessments will be released in 2014/2015.
Figure 8.3: Number of Blue Drop Certifications.
The prior year nine Blue Drop certifications comprise:
|1.||eThekwini Main (Midmar, DV Harris, Durban Heights, Wiggins, Maphephethwa, Amanzimtoti and Hazelmere WTW) with eThekwini Metropolitan Municipality||6.||Howick, Camperdown and Mshwati (Midmar and DV Harris WTW) with uMgungundlovu District Municipality|
|2.||Msunduzi (Midmar and DV Harris WTW) with Msunduzi Local Municipality||7.||Dolphin Coast (Hazelmere WTW) with iLembe District Municipality and Sembcorp SIZA Water|
|3.||Ixopo (Ixopo WTW) with Sisonke District Municipality||8.||Groutville (Hazelmere WTW) with iLembe District Municipality|
|4.||Mathulini, Mthwalume and Qoloqolo (Mthwalume WTW) with Ugu District Municipality||9.||Ndwedwe (Hazelmere WTW) with iLembe District Municipality|
|5.||Mzinto and Pennington to Scottburgh (Mzinto WTW) with Ugu District Municipality|
Wastewater Quality Performance
The performance of the wastewater treatment works is assessed against the relevant licence or General Authorisation General Limits prescribed by the Department of Water Affairs (DWS). For 2012/2013, the overall effluent compliance was 86.2%.
Table 8.2: Wastewater compliance per treatment works
|Volume %||Compliance (%)|
|Albert Falls North||0.01||0.01%||77.1%||69.7%||72.2%|
|Albert Falls South||0.01||0.01%||54.0%||N/A||N/A|
Albert Falls South: The works is currently undergoing refurbishment and the load to this site is being tankered to the Albert Falls North WWTW for treatment.
Umgeni Water set an achievable target of ≥85% compliance for wastewater for 2012/2013. The organisation has achieved this target and the gap to full compliance is 13.8%. The gap is expected to close following the Darvill Wastewater Treatment Works upgrade scheduled for 2015.
Reasons for gap to address full compliance and action plans
At the Darvill WWTW, the variance is mainly attributable the plant operating above its design capacity resulting in process related problems. Inadequate aeration capacity of the activated sludge process and solids carryover further contributed to non-compliances. Some rain events resulted in the filling of the storm dam and discharge of untreated sewage. Trade effluent discharge problems were also a contributing factor to poor effluent quality.
At Ixopo WWTW variations in the volumes of influent entering the plant, over-aeration, solids carryover and disinfection problems, contributed to the poor effluent quality. At Howick WWTW non-compliances were mostly due to very high mixed liquor suspended solids in the reactor units, largely as a result of problems with de-watering equipment, whilst drying beds were significantly affected by rain events. Reduction in plant capacity due to problems with the aerators and mixers, process overloading and aeration also contributed to the failures.
Over the year, significant effort has been made to improve process functioning and has proven beneficial. In particular for the Darvill WWTW various rehabilitation and upgrade projects have been budgeted for and are in progress, including a major works upgrade. At Ixopo WWTW information provision to the Municipality on low sewer volume issues is on- going. New chlorination equipment has been installed and a project is underway to build a second clarifier unit. At Howick WWTW, process improvement efforts are ongoing.
Green Drop Certification Preparedness
Umgeni Water initiatives in the year included completion of internal process audits for all wastewater treatment works, identifying optimal water quality monitoring programmes for each site, developing multi-year training plans to address the skills gap to meet the requirements of the Water Services Act, Regulation 17, registration of superintendents and process controllers and overall preparedness to facilitate DWA assessments.
Research and Innovation
In the year Umgeni Water approved its Innovation Policy, the purpose of which is to provide a favourable corporate environment for innovative suggestions to emerge. Umgeni Water will benefit from this through its employee working differently and more creatively serve the organisation and sector’s needs.
The utilisation of new technology and processes to improve efficiencies and increase effectiveness within Umgeni Water’s operations is considered a key component of moving the organisation forward in its growth phase. A large portion of the knowledge gained in new technology and processes that will be applicable to the organisation is through the innovation, research and development (IRD) projects that are undertaken by the organisation itself and by the University of KwaZulu- Natal (UKZN) for the organisation through the UW/UKZN Chair of Water Resource Management which is now operational.
Umgeni Water plans and implements several projects for which work completed is shown in Table 11.1
Table 11.1 Umgeni Water’s major research projects and progress made in 2012/2013.
|Research Project||Objectives||Progress 2012/2013|
|1.||Nano-structured Titanium oxide Nitrogen Doped Photo-Catalytic Membranes for Water Treatment (NATIOMEM)||To test the disinfection efficiency of a membrane pilot plant that uses sunlight for disinfection without any chemical addition.
The intention is to use the technology to provide safe drinking water for a rural household.
|All planned pilot trials were successfully completed and a ceramic membrane successfully coated with nitrogen doped titanium dioxide to enable chemical-less disinfection.|
|2.||Monitoring of Endocrine Disrupting Compounds (EDC) Levels in Darvill WWTW||To determine and optimise an analytical technique for the detection and quantification of endocrine disruptor compounds in Darvill wastewater.||The method development and validation is in progress.|
|3.||Evaluation of High-rate Clarifiers (HRC).||Investigate and demonstrate the use of high- rate clarifiers at Umgeni Water WTW sites.
Prepare design guidelines for the optimisation of high-rate clarifier design and construction.
|All experimental work on the HRC, at alternate site, Mvoti WTW, is complete (in the prior year the data collected assisted in the selection and design of an appropriate clarifier unit for the Hazelmere WTW upgrade). The technology is suitable for potable water treatment and a site is being sought for the full scale application of the technology.|
|4.||Evaluation of Direct Up- flow Filters (DUF) for Potable Water.||Test the applicability of the Direct Up-flow Filter technology for use at Umgeni Water WTW.
Compare cost-effectiveness of the technology from an operations and maintenance perspective.
|Plant trials testing the applicability of technology are complete and Umgeni Water is planning to relocate the plant to a suitable rural area.|
In addition, Umgeni Water has kept current with the latest development in analytical techniques. Current research focus areas are:
- Radioactive screening: Tests for uranium, and alpha-beta radioactivity, was undertaken on fifty (50) raw and drinking water monitoring sites. The tested catchments showed no radiation contamination,
- Endocrine Disrupting Compounds: The levels of Endocrine Disrupting Compounds (EDCs) at Darvill Wastewater Treatment Works was studied to establish removal efficiencies from conventional treatment and compared to MBR treatment. Enzyme-Linked Immunosorbent Assay (ELISA) and GC MS analysis methods are being developed for EDCs,
- Polymers for water treatment: A test method using gold nanoparticles was developed in collaboration with UKZN to measure polymer residues in water,
- Soil testing: New methods for thirty-six (36) different analyses are being developed and validated for the analysis of soils as required by the new Sludge Guidelines. A fully fledged soil testing laboratory is being designed for this purpose.
- Other areas of research include real time PCR and enteric viruses