Core Services

Core Services

1.        Bulk  Provision and Infrastructure Assets

The core bulk water and wastewater business is undertaken in a manner that most effectively serves customers and stakeholders. As part of the value chain function, raw water is carefully abstracted from dams, rivers and groundwater sources and conveyed using both gravity and the most effective pumping options to bulk water treatment works, where it is treated to meet SANS 241 quality standards and distributed to customers.

Equally, with regards to wastewater treatment, influent is received from municipal sewer systems, treated at bulk wastewater treatment works and effluent is discharged back into receiving systems mindful of the quality and potentially impacts on receiving systems and potential for reuse.

Umgeni Water’s infrastructure assets in support of its bulk water services business comprise:

  • Approximately 1260 kilometres of pipelines and sixty-seven (67) kilometres of tunnels,
  • Fifteen (15) impoundments,
  • Twenty (20) water treatment works, and
  • Eleven (11) wastewater treatment works. 

A total of 472 million cubic metres of potable water per annum (1294 Ml/d) are currently supplied to customers (Figure 1.1) who serve a population of 6.7 million or 1.9 million households through reticulation networks.

The entity treated bulk wastewater totalling 29 million cubic metres per annum (80 Ml/d) (32 million cubic metres or 87 Ml/d in 2018). The capacities of the different wastewater treatment works are shown in below (Figure 1.2). 

2.        Water Quality Management Approach

The quality of potable water is paramount to Umgeni Water thus the organisation endeavours to ensure that the quality of potable water produced within its operational area is safe to consumer health over a lifetime of consumption.  In order to achieve this, a comprehensive water quality management programme is implemented throughout the supply area. The programme adopts a risk-based approach including:  monitoring programmes, water quality assessments, system audits, compliance reporting and water safety plans embracing the catchment to consumer concept.

The risks associated with abstraction, conveyance, treatment and bulk distribution are constantly reviewed to ensure control effectiveness and quality assurance. Potable water quality incidents are managed in accordance with an Incident Management Protocol aligned to the requirements of the South African National Drinking Water specification (SANS 241).

In addition to providing safe drinking water and protecting public health, Umgeni Water is also committed to ensuring that wastewater discharges are not harmful to the environment and downstream users. This is achieved through the development and implementation of wastewater risk abatement plans which include comprehensive and site specific risk assessments, the implementation of corresponding mitigation plans and site specific incident management protocols to manage wastewater incidents and non-compliances.

All potable and wastewater sampling and analysis are undertaken in accordance with an ISO 9001 certified monitoring programme and SANAS 17025 accredited laboratory methods. Information on water quality performance is regularly conveyed to customers, stakeholders and regulators in accordance with the organisational stakeholder communication plan.

2.1 Potable Water Quality Performance

The South African National Drinking Water Specification (SANS 241:2015) dictates the compliance requirements for potable water supply systems. The performance of each system is reported against the following five risk categories specified in SANS 241:2015 (as per the classification tabulated further below):

(1) Acute Microbiological Health,

(2) Acute Chemical Health,

(3) Chronic Chemical Health,

(4) Aesthetic, and

(5) Operational categories. 

Key to classification of the performance of drinking water supply systems according to SANS 241: 2015

Population up to 100 000

Proportion of samples compliant

Population > 100 000

Proportion of samples compliant

Excellent Good Unacceptable Excellent Good Unacceptable
Acute Microbiological Health ≥97% ≥95% <95% ≥99% ≥97% <97%
Acute Chemical Health ≥97% ≥95% <95% ≥99% ≥97% <97%
Chronic Chemical Health ≥95% ≥93% <93% ≥97% ≥95% <95%
Operational ≥93% ≥90% <90% ≥95% ≥93% <93%
Aesthetic ≥93% ≥90% <90% ≥95% ≥93% <93%

 

For the assessment period 2018/19, thirteen (13) Umgeni Water bulk water supply systems and four (4) uMgungundlovu District Municipality (UMDM) schemes were monitored and reported against the five risk categories as specified in SANS 241:2015.

In March 2019, Umgeni Water acquired three (3) small water treatment works schemes from Uthukela District Municipality (uTDM) including: Ezakheni WTW, Oliphantskop WTW and Thukela Estate WTW.  These schemes were also monitored and reported against the five risk categories as specified in SANS 241:2015. Umgeni Water intends on assessing, maintaining and refurbishing or consolidating these schemes to provide a more sustainable bulk water solution to the areas supplied by the schemes in a similar manner that has been accomplished with the UMDM schemes.

Overall, compliance of the Umgeni Water bulk potable water supply systems was excellent for the reporting period. Compliance per SANS 241:2015 risk category is shown in Figure 2.1. Detailed potable water quality compliance per water supply system is shown in Table 2.1.

Table 2.1: 2018/2019 Potable Water Quality Compliance (%) with SANS 241:2015 per Water Supply System

 

Water Supply System Average daily volume treated (Ml/d) % Volume Percent Compliance with SANS 241:2015
Acute Microbiological Health Acute Chemical Health Chronic Chemical Health Operational Aesthetic
1 Durban Heights 503.0 35.65% 100 100 100 99.98 100
2 Wiggins 274.0 19.42% 100 100 100 99.84 100
3 Midmar 275.0 19.49% 100 100 100 99.65 100
4 DV Harris 95.0 6.73% 99.79 100 100 99.82 100
5 Amanzimtoti 80.0 5.67% 100 100 99.92 99.49 99.95
6 Hazelmere 59.0 4.18% 100 100 99.86 99.84 100
7 Lower Thukela 29.0 2.06% 100 100 99.87 99.7 100
8 Maphumulo 7.0 0.50% 100 100 99.78 96.35 98.61
9 Umzinto 14.0 0.99% 100 100 99.67 100 100
10 Mtwalume 12.0 0.85% 98.82 100 100 100 100
11 Mhlabatshane 6.0 0.43% 100 100 100 99.69 100
12 Maphephetheni 4.0 0.28% 100 100 100 99.64 100
13 Ixopo 2.3 0.16% 98.36 100 99.65 95.04 98.36
14 Mpofana 5.9 0.42% 98.81 100 100 96.53 100
15 Appelsbosch 0.4 0.03% 100 100 100 99.62 100
16 Rosetta 0.2 0.01% 100 100 100 99.26 100
17 Lidgetton 0.5 0.04% 100 100 100 95.58 100
18 Ezakheni* 37 2.62% 96.43 100 100 79.66 97.2
19 Thukela Estate* 0.8 0.06% 88 100 97.89 62 77.17
20 Oliphantskop* 6.0 0.43% 92.86 100 100 72.03 86.41

* System operated and monitored by Umgeni Water since March 2019

  The UMDM drinking water supply systems recorded a combined excellent performance against all the risk categories specified in SANS 241:2015. Since UW acquired these sites in 2016, an increasing trend in compliance is noted.  This is largely due to a number of interventions that have been implemented by UW including: the installation of 2Ml/day package plants at Mpofana WTW and Lidgetton WTW, the drilling of boreholes at Applesbosch WTW & Lidgetton WTW and the refurbishment of the slow sand filters at Applesbosch WTW.

The uTDM drinking water supply systems viz. Ezakheni, Oliphantskop and Thukela Estate recorded excellent performance against the Acute Health Chemical and Chronic Health Chemical risk categories whilst unacceptable performance was recorded in the Acute Health Microbiological and Operational risk categories. The Ezakheni system recorded excellent performance against the Aesthetic risk category whilst the Oliphantskop and Thukela Estate systems reported unacceptable performance. This was due to a number of issues including: varying raw water quality, the lack of optimisation or malfunction of treatment chemical dosing systems, challenges with the gravity sand filters, insufficient disinfection and aging plant infrastructure. Various mitigation measures have been implemented to improve compliance including process optimisation and the training of process controllers. Refurbishment of the treatment units at some works has also been instituted.

2.2 Wastewater Quality Performance

Figure 2.2 and Table 2.2 show wastewater quality compliance per system, assessed against the relevant licence or General Authorisation General Limits prescribed by the Department of Water and Sanitation (DWS). 

Table 2.2: Wastewater compliance per treatment works

Wastewater Treatment Works Average daily volume treated 2015 2016 2017 2018 2019
(Ml/d) (%)
1 Darvill 67.2 83.7% 85% 82% 72% 73.8% 73.7%
2 Howick 5.5 6.9% 87% 89% 86% 91.1% 90.3%
3 Ixopo 0.5 0.6% 96% 93% 94% 96.0% 94.0%
4 Lynnfield Park 0.2 0.3% 87% 86% 96% 95.9% 93.6%
5 Mpofana 5.6 7.0% 65% 72% 78.0% 77.7%
6 Richmond 0.6 0.7% 89% 87% 93.9% 96.7%
7 Cool Air 0.4 0.5% 90% 98% 98.2% 99.6%
8 Camperdown 0.2 0.2% 91% 97% 91.7% 91.7%
9 Applesbosch 0.1 0.1% 94% 91% 81.9% 88.9%

 

Effluent compliance for the Umgeni Water Bulk Wastewater Systems decreased marginally from 81.7% to 81.29% for the reporting period.  Once again, an increasing trend in effluent compliance is noted for the UMDM sites following a number of interventions that have been implemented by UW including: process optimisation, installation of electrical panels and aerators and the refurbishment of a number of process units. A notable increase in effluent compliance was observed at Mpofana WWTW where a number of mitigation measures were implemented such as the refurbishment of the clarifiers, upgrade of pumps, optimisation of the sludge dewatering machine and the dredging, refurbishment & reconstruction of the reed beds.

The non-compliance recorded for Darvill WWTW was mainly due to construction related activities as well as process overloading, trade effluent inputs, power outages and intermittent spillages from the storm dam. The upgrade work currently remains on hold, with some process components being incomplete thus compromising the efficiency of the treatment process. The completion of the works upgrade project remains critical to increase capacity and improve effluent compliance.  The proposed constructed wetland, for detention of some storm dam spills, will also have a significant benefit once completed.

 

Management Approach

The quality of potable water is paramount to Umgeni Water thus the organisation endeavours to ensure that the quality of potable water produced within its operational area is safe to consumer health over a lifetime of consumption.  In order to achieve this, a comprehensive water quality management programme is implemented throughout the supply area. The programme adopts a risk-based approach including:  monitoring programmes, water quality assessments, system audits, compliance reporting and water safety plans embracing the catchment to consumer concept.

The risks associated with abstraction, conveyance, treatment and bulk distribution are constantly reviewed to ensure control effectiveness and quality assurance. Potable water quality incidents are managed in accordance with an Incident Management Protocol aligned to the requirements of the South African National Drinking Water specification (SANS 241).

In addition to providing safe drinking water and protecting public health, Umgeni Water is also committed to ensuring that wastewater discharges are not harmful to the environment and downstream users. This is achieved through the development and implementation of wastewater risk abatement plans which include comprehensive and site specific risk assessments, the implementation of corresponding mitigation plans and site specific incident management protocols to manage wastewater incidents and non-compliances.

All potable and wastewater sampling and analysis are undertaken in accordance with an ISO 9001 certified monitoring programme and SANAS 17025 accredited laboratory methods. Information on water quality performance is regularly conveyed to customers, stakeholders and regulators in accordance with the organisational stakeholder communication plan.

Potable Water Quality Performance

The South African National Drinking Water Specification (SANS 241:2015) dictates the compliance requirements for potable water supply systems. The performance of each system is reported against the following five risk categories specified in SANS 241:2015 (as per the classification tabulated further below):

  1. Acute Microbiological Health,
  2. Acute Chemical Health,
  3. Chronic Chemical Health,
  4. Aesthetic, and
  5. Operational categories.

 

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
Durban Heights 562 43% 100 100 99.98 100
Wiggins 270 20% 100 100 100 100
Midmar 267 20% 100 100 99.91 99.94
DV Harris 88 7% 100 100 99.87 100
Hazelmere 52 4% 100 100 98.58 100
Amanzimtoti 21 2% 100 100 99.53 100
Mvoti 19 1% 99.05 100 95.86 99.84
Mzinto 13 1% 100 100 98.28 98.22
Mtwalume 10 1% 100 100 99.32 100
Maphumulo 6 0.5% 100 100 99.73 100
Maphephethwa 2.9 0.2% 100 100 92.96 100
Ixopo 2.4 0.2% 100 100 100 99.72
Ngcebo 0.6 0.05% 100 100 98.03 99.42
Mhlabatshane 0.5 0.04% 100 100 94.92 100
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

 WWTW  Volume
(MI/d)
 Volume %  Compliance (%)
2011 2012 2013
Darvill 85.5 93% 80.5% 86.0% 87.0%
Howick 5.8 6% 83.1% 92.0% 82.7%
Ixopo 0.8 0.87% 95.4% 83.2% 88.1%
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:

  1. 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,
  2. 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,
  3. Polymers for water treatment: A test method using gold nanoparticles was developed in collaboration with UKZN to measure polymer residues in water,
  4. 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.
  5. Other areas of research include real time PCR and enteric viruses