Development of a tool to support operationalising water safety plans: experiences from a national water utility in Ghana

Since their incorporation into the 2004 version of the World Health Organization's (WHO's) Guidelines for Drinking Water Quality (GDWQ) (WHO 2004), Water Safety Plans (WSPs) continue to be the pre-eminent process for the delivery of safe drinking water to consumers. Water safety planning achieves this by prioritising proactive, rather than reactive, management of risks to drinking water quality (WHO 2005, 2023).

In 2017, WHO and the International Water Association (IWA) released a comprehensive review on the national adoption of WSPs (WHO & IWA 2017), which found that WSPs had been developed and implemented in 93 countries worldwide.

In Figure 1, Module 6 is highlighted, as the primary aim of this project was to create an operational framework to support improved implementation of this module within suppliers that have had difficulties in achieving effective implementation.

The field component and write-up of this project were undertaken in late 2019 and early 2020, prior to the release of a second edition of the WSP Manual (WHO 2023). The second edition of the Manual, while still based on 11 modules, has revised titles for each of the modules. This paper uses the module titles that were current at the time of the project.

Despite the widespread adoption of WSPs, and the production of a range of supporting resources to assist water suppliers in preparing and implementing WSPs (WHO 2016, 2019; Setty & Ferrero 2021), a number of barriers to successful WSP implementation continue to exist (Ferrero et al. 2019). Kumpel et al. (2018) looked at the effectiveness of WSP implementation across 99 water supply utilities in 12 countries in the Asia-Pacific region. This study identified the benefits that arose from the adoption of WSPs, but it also identified a number of challenges to their effective implementation, including financial constraints and insufficient capacity.

Comprehensive reviews of WSP implementation, and associated barriers have also been undertaken in Germany (Schmiege et al. 2020) and Vietnam (Nguyen et al. 2023). Consistent with Kumpel et al. (2018), a number of barriers to local WSP implementation were found. In the case of Germany, amongst other issues, developing a national WSP strategy, securing financial instruments, and undertaking activities to support the continual implementation of WSPs appeared to be scarce (Schmiege et al. 2020), while, in Vietnam, key barriers to WSP implementation were a lack of WSP guidance suitable for the local context and insufficient funds for WSP implementation (Nguyen et al. 2023).

While the barriers and challenges identified in the quoted articles are not the focus of this paper, what they highlight is that, despite the clear benefits that WSPs bring to the ongoing provision of safe drinking water, the universal adoption, and effective and sustained implementation of, water safety planning remains elusive.

Developing and documenting the WSP is an important first step in the management of risk, but a WSP's role as an operations and management tool needs to be emphasised (WHO 2019). The emphasis on developing and documenting the WSP can result in a tendency for WSPs to focus primarily on risk assessment and improvement planning, rather than also giving due attention to the ongoing operations, management, monitoring and review aspects of water safety planning. It is the latter elements of a WSP that underpin its effectiveness and sustainability, by making clear that water safety planning is not a one-off event intended only to identify and address current problems, but instead, that effective WSPs rely on a long-term commitment to improved system management. Having due regard for this aspect of WSPs facilitates their integration into routine operations.

For the purposes of this paper, the operationalisation of a WSP, or, alternately, operationalising a WSP, refers to the integration of the WSP into routine operations, whether this be within the catchment area of the water supply system, or across any associated water treatment facilities or distribution network.

In practical terms, operationalising a WSP requires its implementation in the field, particularly in relation to the implementation of Module 5 (implementing improvements) and Module 6 (monitoring of control measures). These operational aspects are critically important to achieving and sustaining the benefits of water safety planning.

Ghana Water Company Limited (GWCL), which is the major water supplier to urban areas in Ghana, was an early adopter of WSPs. Since 2004, GWCL has been working in collaboration with the country's Public Utilities Regulatory Commission (PURC) on the development of WSPs for various water supply systems. In 2018, PURC included WSPs as a key performance indicator (KPI) for GWCL. Consequently, management identified the need for the development of a framework that would facilitate and promote the standardisation of WSP implementation across the 96 water supply systems managed by GWCL.

GWCL has developed WSPs for a number of water supply systems, however, sustainable implementation of these WSPs has remained elusive. The key challenges to the adoption of WSPs were identified as a lack of an operational policy and guidance document, and inadequate capacity to develop the framework.

This paper describes the approach that was undertaken to address this implementation gap through the development of an operationalisation framework that would help support sustainable WSP implementation across the water supply systems operated by GWCL.

In early 2018, GWCL approached WHO and IWA, seeking support to undertake a project to strengthen the adoption and implementation of WSPs across GWCL's water supply systems. With support provided by United Nations International Children's Emergency Fund (UNICEF), WHO engaged WSP experts from two water utilities, Yarra Valley Water and Coliban Water, which are based in the Australian state of Victoria, to deliver the project.

An important aspect of the project was that it was structured on a peer-to-peer model, where operational experience on the day-to-day management of water treatment plants (WTPs) within a WSP could be shared and discussed.

Both Yarra Valley Water and Coliban Water have close to 17 years of experience with the development and implementation of WSPs, as Victoria was one of the first jurisdictions in the world to include a formal legal requirement for WSPs in its drinking water legislation (Safe Drinking Water Act 2003, Victorian Government, Australia). Victoria's Safe Drinking Water Act, which commenced on 1 July 2004, required all Victorian water suppliers to develop and implement WSPs by 1 July 2005. The risk management framework that underpins the requirements of the Act is detailed in the Australian Drinking Water Guidelines (ADWG) (NHMRC 2011). The risk framework detailed in the ADWG largely mirrors the content of WSPs contained in the GDWQ.

The primary output for the project was the development of a framework that would allow GWCL to operationalise its WSPs. The approach focussed on developing such a framework for a trial site, which could then be scaled-up to all WTPs under GWCL's operation.

Kwanyako WTP was chosen as the trial site because a draft WSP had been developed for the WTP and associated water supply system, but finalisation and implementation had stalled. This site was also considered to be representative of other systems operated by GWCL.

In October 2019, two WSP experts from Coliban Water spent 4 days in Ghana working first-hand with operational staff at the Kwanyako WTP, in order to fully understand the operation of the water supply system and associated challenges.

In the company of operational staff, and using their site knowledge and expertise, the water treatment process was tracked from the point where raw water was extracted from the Ayensu River to when the fully treated water was sent to the townships of Kwanyako, Agona Swedru, Agona Nyarkrom, Mensakrom, Bawjiasi, and Budumburam.

The Kwanyako WTP is what is generally described as a conventional WTP, in that it consists of a clarification step, followed by dual media filtration and then chlorination. At the time of the visit, there was limited automation at the plant, with processes such as the backwashing of the dual media filters being undertaken manually.

In addition to the site visit, meetings were held with both senior water quality staff and management at GWCL, to gain an understanding of how the principles and practices of WSPs had thus far been embedded into the organisation, and to seek to identify additional opportunities to enhance current practices.

The field visit was conducted on a single day, and the catchment area and the townships that are supplied by the Kwanyako WTP were not visited. A detailed report on opportunities for operational improvement in Kwanyako WTP was prepared, along with the creation of a more generic operational framework that could be adapted and applied to other WTPs operated by GWCL. The catchment and distribution aspects reflect current good practice, but only the operational, treatment aspects draw from the direct observations at the Kwanyako WTP.

The first output from the in-country work was a detailed report on operational improvements that could be made at the Kwanyako WTP to improve plant performance. One important aspect of the report was the identification of likely critical control points (CCPs) across the WTP, and the specification of alert and critical limits for each CCP, in line with Hazard Analysis Critical Control Point (HACCP) principles.

While mentioned in both the first and second editions of the WSP Manual, the application of HACCP principles within a WSP is not explored in detail. In summary, HACCP was developed to assist the food industry in ensuring that potentially unsafe foods are quickly identified during the manufacturing process, and it has subsequently been adopted by water suppliers as a way of managing the performance of treatment processes (APHA 1972; AIFST 1989; Havelaar 1994; Deere & Davison 1998).

A hazard analysis (HA) is undertaken, which is the first element of the risk assessment undertaken as part of a WSP. The outputs of the HA are used to identify those points that are critical to the production of safe drinking water, specifically at those points in the process where operational control can be exerted over the process, known as CCPs.

At each CCP, alert and critical limits are put in place. If an alert limit is breached, it alerts operational staff that a water treatment process is tending towards failure. If a critical limit is breached, then the water treatment process has failed and there is a higher probability that unsafe drinking water is being produced.

In a tabular format, the recommended CCPs and their associated alert and critical limits, along with target values for each process, are presented in Table 1. Also included in Table 1 is the rationale for classifying these particular points in the treatment process as CCPs.

Following extensive engagement with operational staff, the critical and alert limits were tailored to reflect the local circumstances (for example, the limited availability of process automation at the WTP at the time of the site visit). In modifying some of the limits, it was important that while some of the values were less stringent than what might be applied at WTPs in Australia if the proposed limits were consistently met, there was still a high probability that the water being produced by the Kwanyako WTP would be safe to use as drinking water.

The report was based around a continuous improvement model, where the WTP would be optimised based on the capability and limitations of the available treatment processes, with many of the recommended improvements being either no-cost, or low-cost, changes to current operation, but, as funds became available to invest in any necessary capital upgrades, the alert and critical limits could be reviewed and tightened, as appropriate.

The information and recommendations in the report could also be fed back into the draft WSP for the Kwanyako water supply system, in order to further develop Modules 5 and 6 of the WSP so that they were reflective of current operational practice at the Kwanyako WTP.

The second, and more substantial, part of the project was the development of an operational framework document that could be applied across all of GWCL's water supply system, as the basis of Modules 5 and 6 of any WSP.

Many comprehensive and high-quality guides have been produced to assist water utilities of varying sizes and circumstances in developing WSPs (WHO 2005, 2023). A potential limitation has been that these guides have generally not gone into great detail on how the water should be treated, and what operational controls should be put in place to manage the treatment processes are being used. In many respects this makes sense, as WSPs guides and manuals are not designed to be treatment handbooks; they are primarily designed to assist water utilities in identifying and assessing risks to drinking water quality, and then put in place controls to manage the risk.

A more relevant guide is the second edition of Water Research Australia's Good Practice Guide to the Operation of Drinking Water Supply Systems for the Management of Microbial Risk (2020). This comprehensive guide is designed largely as a resource for high-income countries, with mature WSPs, rather than those countries that may still be implementing a WSP.

The operational framework that was produced as an output of the project provides an overview of the minimum requirements for the preparation and implementation of the operational aspects of a WSP across a water supply system in countries where water safety planning is still very much the development phase, as is the case for many systems operated by GWCL. The framework document is not intended to replace any applicable local regulatory requirements with respect to WSPs, or the development of a more detailed WSP, but, rather, it is intended to provide ‘checklist-style’ guidance on important aspects of WSP implementation in a user-friendly and accessible format.

The framework document is divided into three distinct sections in line with GWCL's mandate: Catchment (Table 2), Treatment (Table 3), and Distribution (Table 4), and provides information on the minimum requirements for each part of the catchment-to-consumer WSP framework. It also includes a list of good practice general requirements (Table 5).

With respect to Table 4, it is important to note that, while the WSP is structured around the management of risk from the catchment to the consumer, which implies the WSP will address risks beyond the point of delivery to the consumer (i.e. beyond the water meter), like many water suppliers, GWCL's responsibilities stop at the customer meter, so aspects beyond this were not included in the document.

One of the ongoing challenges with the implementation of WSPs is how to apply them to existing water supply systems, particularly where the water supply system includes an existing WTP. This is because either the operational controls that have been established for the WTP may not have been set with contemporary public health or treatment limits in mind, or the available treatment processes are not reflective of current source water risks. This issue can be exacerbated by a widely-held assumption that the WSP needs to be implemented in addition to the current operational controls and processes.

One of the objectives of this project was to demonstrate to the operational staff at the Kwanyko WTP that much of their current day-to-day operational practice at the WTP was consistent with the content and intent of the draft WSP so that the implementation of the WSP did not mean that all current practices had to be replaced, but equally that the content of the draft WSP would not just be added on top of current practice at the WTP.

What needs to occur is that current operational practice across a water supply system needs to be viewed through a WSP lens, so that good operational practices are retained and form the basis of Modules 5 and 6 of the WSP, outdated practices are updated, inappropriate practices are removed or cease, and gaps identified, where new operational procedures need to be developed and implemented.

The second objective of the project was to develop an operational framework that, when implemented, would form the basis of good operational practice at all of GWCL's WTPs. The elements within the operational framework document were developed with those countries that are still in the WSP development stage in mind, and represent a set of elements that, if fully implemented, can assist water suppliers in achieving the safe management of drinking water supplies.

The elements included in the operational framework are a distillation of information contained within more comprehensive operational guidance documents (e.g. as produced Water Research Australia (2020)), or more recent WHO documents (such as, A field guide to improving small drinking water supplies: water safety planning for rural communities (2022b)). The elements are also not intended to replace more comprehensive assessments and tools that would support the implementation of Modules 5 and 6 of the WSP, but they are intended as scalable starting points.

The value of doing a site tour, and discussing water quality and treatment issues and challenges with operational staff, should not be underestimated, as this provides important insights into current operational practice.

Having input from operational staff is an important aspect of WSP development, as it helps ensure that the operational aspects of the WSP are achievable and reflect the current capabilities and limitations of treatment processes. The adoption of water safety planning is less likely to occur if operational staff feel removed from the process.

After the conclusion of the project, GWCL began the process of turning the operational framework into an endorsed company policy. The endorsed policy document was launched in October 2022, and it can be downloaded from the WHO/IWA Water Safety Portal (https://wsportal.org/find-wsp-resources).

Since the launch, GWCL has undertaken further training on WSPs, with the long-term view of using the operational policy to support the development and implementation of WSPs across all its water supply systems.

Some of the improvements in water safety planning that have been achieved are:

• The identification of, and discussion on the importance of, adding additional CCPs within WTPs, and how this would improve the effectiveness of the water treatment processes in use.

• Knowledge sharing, and providing access to current literature and reference materials.

• Providing supporting literature and scientific argument that highlighted the need for GWCL to engage the country's National Committee to discuss a review of water quality standards, specifically in relation to the turbidity standards for filtered and final water. The existing Ghana Standard value for final water is 5NTU, while the recommended international value is <1NTU. Lowering the value would help minimise potential health risks, by supporting improved filter performance.

Additionally, the operational framework provides one-stop access to all the critical minimum requirements for the catchment, treatment, distribution as well and customer responsibilities.

It should also be noted that the operational framework could be used as a checklist when undertaking internal and external WSP audits.

Further work needs to be undertaken to verify the operational framework has resulted in improved implementation of WSPs at other water supply systems, as well as sustained and sustainable changes in operational practice.

In a broader context, the operational framework developed as part of this project can support other countries with the implementation of water safety planning, with a checklist of tangible actions that can be adapted and applied to help improve the safety of drinking water supplies.

The authors would like to acknowledge the operational and technical support to the project provided by Ms Margaret Macauley, Chief Manager, Water Quality Assurance and Mr Mark Tettey Ayertey, Senior Water Quality Expert, at the Ghana Water Company Limited. The authors would also like to acknowledge the valuable support by Mr Kizito Masinde, currently Global Events and Awards Director at the International Water Association, and Mr Samuel Amoako-Mensah, WASH specialist at UNICEF, who is based in Accra, Ghana, provided to this project.

All relevant data are available from an online repository or repositories.

The authors declare there is no conflict.