Abstract
Tanzania, like other developing countries, experiences frequent water supply project failures during its operations leading to subsequent loss in revenues annually which is mainly attributable to pumping system failure. While a lot of investment is spent on establishing new water supply projects, little attention is paid to the functioning of these systems, leading to the abandonment of most projects due to pump failures. The purpose of the study was to assess the operational situation of water pumps and develop an appropriate application for early faults detection to foster prompt remedial actions. A site visit and online survey with questionnaires were performed to collect information on water pump problems in 13 regions in Tanzania. The study revealed that 82% of pumps face excessive power consumption, 53% fail due to broken seals, 41% encounter no or low flow, 35% have no or low pressure and 24% produce excessive noise or vibration. The Pump Diagnosis Tool (PDP) application is developed to provide rapid insight into the condition and state of the pumping system and the required measures to address the problem. The PDT has the potential to detect and diagnose pump problems in a timely manner to avoid total failure which is potentially the major driver behind water supply work breakdowns.
HIGHLIGHTS
Water supply projects are subject to frequent failures.
Excessive power consumption is a common water pump problem.
Water pump professionals' interaction is the key.
Web and mobile application for fault detection.
Know-what, know-when and know-how for water supply sustainability.
Graphical Abstract
INTRODUCTION
Water pumps constitute the most essential but most vulnerable part of a water supply storage and distribution network. Pumps are also significant determinants of water supply reliability and therefore determine the success or failure of a water supply system. Africa still faces major challenges in portable water availability and reliability where rural areas suffer the most (Tadesse et al. 2013). For African countries to attain Sustainable Development Goal (SDG) 6 by 2030, more efforts need to be directed not only to the appropriate design and installation of water supply systems but also to maintain the functionality of these systems (African Union 2017). For example, in Tanzania, there are 23 million people who do not have access to safe water and are forced to walk miles in order to fetch water for their daily needs (Bejarano et al. 2018). While significant initial capital is needed to install these systems, a sustained long-term effort and investment are also required to maintain vulnerable parts that pose frequent operational constraints, for instance, pumps (Bejarano et al. 2018).
In the past decade, Tanzania has made a substantial investment in installing new water supply projects in rural areas. According to the Water sector Status Report of 2020, the Water Sector Development Programme (WSDP) II target for Rural Water services was to increase a total of 76,334 water points by June 2019. Still, Rural Water Supply and Sanitation Agencies (RUWASA) report indicates that a total number of 32,133 water points was established. However, the report reveals that the number of functional projects did not increase substantially as expected. Only two-thirds of all water points were functioning and this was due to failure and breakdowns (MoW 2020). Truslove et al. (2019) emphasized that acceleration toward coverage targets contributes toward unsustainable infrastructure.
The failure and breakdowns of water points are a result of poor maintenance and inefficient functioning of existing infrastructure such as water pumps (Chowdavarapu & Manikandan 2016). Failure of the water pump often makes the water source inaccessible until the pump is repaired (Stewart & Candidate 2003).
The limited number of people with sufficient skill, expertise and experience to diagnose and rectify the basic problems afflicting water pumps is also a problem that the water sector faces (Mothetha et al. 2007). Most of these water pumps are located in villages where they are operated by unskilled manpower. There is no proper technology to assist them in detecting failures in the early stages. According to Society & Sciences (2019), poor management and scarcity of skilled manpower contribute much to the failure of the water supply project rather than the wrong choice of pump. Sahdev (2012) suggests that taking immediate measures when the first symptoms of a problem appear can save the water pumps from permanent failures. It is imperative that these water pumps be correctly monitored, diagnosed, maintained or replaced prior to the pump failing catastrophically to reduce idle time, material cost and labor costs (McKee et al. 2011).
Currently, various water pump troubleshooting guides from different water pump suppliers exist online. These guides have been of much help in the general determination and fixing of water pump problems. However, the solutions that exist are general, and sometimes when applied, you might find that the problem still exists or the pump may operate for some time, then the problem re-occurs again (Garcia et al. 2004).
Recently, there has been the development of diagnostic systems which prefer the use of sensors to diagnose pump problems. However, most pumps in the field are old and contain no sensors for measuring data such as temperature, displacement, acceleration, pressure or rate of fluid flow to determine the state of the electric motor and associated electronic equipment on the pump. A room for newer pumps to be provided with sensors exist but despite the provided information, there is no onboard interpretation and assessment of the collected data (McKee et al. 2011).
Pump suppliers would provide the raw data from sensors and information of normal operating ranges, leaving it up to the end user to determine whether the information is to be used in the diagnostics and the prognostics of the pump. In most cases, very little of this information is utilized by the end user, and pumps are still left in either a run-to-fail mode or a scheduled maintenance cycle. Without utilizing data obtained from sensors to diagnose problems, the state of pump diagnosis will remain stagnant in its current practice (McKee et al. 2011).
Digital technology, software and smartphones have been rapidly developing and are playing a massive role in the present way of living (Nuanmeesri 2020); this particular study, therefore, addresses the highlighted challenges by developing a mobile application that will be guidance for detecting early signs of failures in the water pumping system.
This would be the first attempt in Tanzania to develop such an application. This application integrates a database of previous diagnostics, knowledge and expertise formerly used to address similar water pump problems from the pump manufacturers and/or suppliers with the solution obtained from the site experience where the water pump problems have been encountered. It is an application that will enable pump operators to diagnose pump problems and symptoms for repair.
The main components of the tool include input, processing and output interfaces as explained in the flow chart under the Materials and Methods section. The design philosophy of the tool has considered the initiation of the maintenance process by the operator, a database for quick access to pump documentation and a solution to the problem. This is set to enhance efficiency in solving water pump problems unlike more dependence on outside help for maintenance (Thomas 2013). If a community is to manage a water supply system, the technology used needs to be easily manageable by the community caretaker with little outside help (Musonda 2004).
Previous studies in Tanzania (e.g. Chowdavarapu & Manikandan 2016) focused on the mapping of pumps, their functionality status and logistics for repairs at minimum time and cost. However, this was a post-pump failure approach. In this study, it is envisaged that the underperformance or failure symptoms will be captured at the earliest time (Adam et al. 2021) by the operator. This will avoid the failure of pumps and the halting of water supply services.
In a review of major centrifugal pump failure by McKee et al. (2011), the author criticizes the use of sensors or other instrumentation attached to the pumps to interpret water pump problems as not all failures are detected by sensors; for example, corrosion, instead the author commends the use of existing information, where an engineer could use symptoms in order to diagnose the problem, whether by visual inspection, audio inspection or vibration.
Garcia et al. (2004) identified the existence of several programs for the selection of pumps for new installations or upgrades such as Goulds Pumps and Palm hand-held devices where the goal is to identify symptoms and root causes only leaving behind the solution to be adopted to address the problems.
Through the developed application, mechanical and hydraulic failures will be avoided and the lifetime of the water pumps will be improved. It will contribute to the present knowledge gap that still surrounds the rural water sector by providing the upcoming pump operators and engineers with sufficient skills and experience to diagnose and rectify the basic problems afflicting water pumps.
The application will enhance fast interaction between water pump professionals, pump operators and suppliers/manufacturers. It is a platform where pump professionals and suppliers will be located and linked to the market to provide immediate assistance whenever needed while earning their income.
Therefore, this study evaluated the major water pump problems that have been encountered in different water projects in RUWASA in Tanzania. Attention was given to the nature of the faults, symptoms shown within the pump that could be utilized for specific fault detection and diagnosis, and any mechanical corrective procedures from the site or troubleshooting manual that assisted in alleviating the problem in order to prevent the problem from re-occurring. The developed mobile tool will assist in the operation, maintenance and troubleshooting of water pump problems in water supply projects. This is expected to support the efforts of the Government of Tanzania, through the MoW in implementing the WSDP where access to safe water is targeted to increase up to 85% in rural areas by 2025 in order to ensure the sustainability of water projects (MoW 2020).
MATERIALS AND METHODS
The research methods for developing a web and mobile-based android application for early detection of water pump failures include the following steps:
Description of the study area
Stages of tool development
A comprehensive literature review was conducted on aspects related to water pumps in rural water supply projects in Tanzania to give insight into the questions to be included in the questionnaires. Swastikasari et al. (2018) mentioned elicitation as an early stage in the development of an application that involves interviews and questionnaires to understand what is needed by the user of the system designed. Questionnaires containing both open-ended and close-ended questions were prepared and distributed to investigate the phenomena under study with water sector stakeholders (district and regional managers) and pump experts, respectively. A pilot study involving representatives from each of the two sample groups was undertaken to sort out potentially confusing questions. Questions were modified on the basis of the pilot study. The order of the questions was organized to facilitate the respondents' responses and repetitive questions were removed.
Sampling methods
This study required officials who are knowledgeable about the water pumps in water supply projects; hence, a convenient sampling method was used. This method involved a survey of the professionals who were readily available to participate in the study. It is a type of sampling where members of the target population that meet certain practical criteria, such as easy accessibility, geographical proximity, availability at a given time or willingness to participate are included for the purpose of the study (Etikan 2016). The respondents were selected because they were at the right place at the right time (Acharya et al. 2013; Sedgwick 2013). Therefore, RUWASA district and regional managers who were knowledgeable and willing to take part in the study were approached through e-mails to fill out the online questionnaires through the attached link https://forms.gle/ZUmGjy95SGDgPYLw6.
Data collection
The study used well-pre-tested online questionnaires containing both open-ended and close-ended questions on the type of water pumps and water pump problems commonly encountered in water supply projects. Questionnaires were shared through an online link to water sector stakeholders, who are involved directly with the water supply to the communities, and are to be filled and submitted once completed. Some attachments on previous water pump maintenance and troubleshooting activities were requested to assist in the understanding of the water pump problems.
The online questionnaires were found to be the most appropriate data collection method for this study because they were convenient to use as an easy way of reaching the respondents who are spread out in regions across Tanzania. Also, online questionnaires have a tendency to process themselves without further input from the researcher, keeping count of the number of participants, until the point where sufficient data have been collected and the harvest can start (Madge 2006; Fullan 2010). Finally, they have major strengths such as ease of data entry and analysis, convenience, speed and timeliness, flexibility, question diversity, low administration cost, ease of follow-up, control of answer order and ease to obtain a large sample (Evans & Mathur 2005).
Informal discussion with pump professionals was also conducted to establish valuable information regarding water pumps. A site visit to some of the rural water authorities in Dar es Salaam, Morogoro (Morogoro DC, Mvomero, Gairo) and Tanga region as well as pump suppliers was done to get acquainted with the water pump technology and to get input on water pumps from the experts.
Discussions with pump experts and technicians were conducted to get direct information on water pumping units. The field observation helped to gain knowledge on various water pump components and their functions, to identify the standard procedures followed during the installation of the water pumps, proper approaches to be followed during the operation and maintenance stage as well as to get acquainted with water pump problems which are commonly encountered in water supply projects.
Data processing and analysis
Before processing the responses, the completed questionnaires were downloaded into an excel sheet and then edited for completeness and consistency. Data cleaning was done in order to determine inaccurate, incomplete, or unreasonable data and then the quality was improved through the correction of detected errors and omissions. After data cleaning, the data were transferred into the Microsoft word document for further analysis.
The data analysis method used involved a qualitative procedure. The collected data were analyzed qualitatively using a content analysis method based on analysis of meanings and implications derived from respondent information and comparing similar responses from each respondent in order to come up with the common reasonable information to be communicated.
According to Kyngäs et al. (2020), content analysis has been applied to scientific data and its use allows researchers to systematically and objectively describe research phenomena at the theoretical level. Also, the content analysis provides meaningful descriptions of people's experiences and perspectives in the context of their personal life settings.
The design of the mobile application
The application gives the user two options which are the core functions that are troubleshooting and contributing. The user accesses the application to troubleshoot any water-related water pump problem by adding to the tool details required and then submitting. Also, water pump professionals may also access the application to contribute to it any water pump challenges or problems that they have encountered in their daily activities and successful solutions that they used to address such challenges.
Once information on the pump type, pump component and pump symptom/problem is, the application identifies a common keyword from the problem selected and pump type and then compares it with the keyword from the solution existing in the database to give out the most suitable solution for the identified problem. Where the pump problem or symptom does not exist in the database, the information is sent to the tool operator for assistance.
Development of the mobile application
The application development in this study was divided into two phases, which were database designing as well as application and website development which involved translating the collected data into programming language codes.
Database design
Application and website development
The programming language used to develop this application was web application. The web approach is based on web browsers for various mobile devices such as laptops, tablets and smartphones (Zhiming 2016) and is implemented using standard web technologies such as HTML, CSS and JavaScript (Latif et al. 2016; Aldayel & Alnafjan 2017).
The aim of this study was to develop an application that works with Android operational systems hence the programming languages used to develop a website in this study were Hyper Text Markup Language (HTML) which structured the web pages, Hypertext Preprocessor (PHP) which processed server side and communications, CSS which handled the visuals as well as JavaScript which made web pages able to interact with visitors or users
Testing of the developed application
Once the application had been developed, testing of the application was conducted to validate and verify whether the application has understood the problem to be solved as shown in the Results and Discussion section.
RESULTS AND DISCUSSION
Types of water pump commonly used in water projects
Centrifugal (surface pumps) and submersible pumps are the common water pumps encountered in water projects. This is due to the reasons that most of the rural water supply source are either boreholes which require pumps for water extraction or surface water that requires pumps to push water to the storage or distribution units. According to Corporation (2003), centrifugal pumps are preferred compared to other surface pumps because they are economical for large flows and are of low cost for liquids like water.
Common water pump problems
According to Bagloee et al. (2018), water pumps are largely electricity-intensive and are blamed for a large share of the electricity bill associated with running a water distribution system.
Excessive pump power is an indication that there may be a number of different problems going on with the pump. One of the main problems that result in excessive power consumption, and possibly ultimately a motor trip, is the existence of small or high concentrations of particles in the fluid.
Even though the fluid looks clean, it may have a very small concentration of particles that can lead to long-term performance problems as running clearances gradually increase from the wearing down of parts. This can be found in any centrifugal pump application, regardless of how clear or clean the fluid looks. This wearing away produces a loss of hydraulic performance, which will cause the control valve to gradually open wider without being noticed. The wider it becomes, the more power is required from the motor, which may result in a motor trip. This shows that care has to be taken to minimize the effects brought forward due to excessive power consumption.
From the identified problems that afflict water pumps in the water supply projects, various issues dealing with each problem, such as their cause and effect, symptoms, and successful mechanical corrective procedures, were then explored to be incorporated into the application.
The web and mobile-based android application
The mobile application was developed based on five identified problems that acted as a baseline for the development of this application, as seen in Figure 6. The application is web and mobile-based android application known as the Pump Diagnosis Tool (PDT) developed in Android studio (programming platform). The app size is 4.16 MB and can be shared on different mobile sharing platforms such as WhatsApp, Bluetooth and E-mail. The application has three components and it has been designed to access an internet connection in the user device.
Components of the PDT mobile application
The component of mobile application is discussed in the following:
User authentication
The first component of the mobile application is used to verify the system to the user, where users' registration is mandatory to access further into the system through an authentication notification on its page. Notifications are provided and related to a checking mechanism whether the user has registered into the system or not. If the user is not registered, he/she is then required to register according to the required valid data. If all the data are proper, the system automatically responds by giving a notification back indicating that the user has access to the system and can interact with the system by doing a number of activities.
Mobile application interface
Database
Islam & Mazumder (2010) mentioned that mobile application use and development is a new and rapidly growing sector. Mobile devices are common even in areas without access to water services. This shows that there is a potential for using mobile phones as a tool to address different challenges including water-related problems. Mobile phones are an easy way of communicating and disseminating information quickly and thoroughly. Having that in mind, this mobile application will facilitate communication between water pump experts and necessary assistance will be provided to address water pump problems as quickly as possible in order to prevent breakdown.
CONCLUSION AND RECOMMENDATION
This mobile application serves as a guiding tool for pump operators and professionals to use while in the field, thereby enabling them to take advantage of mobile services in taking necessary actions as quickly as possible to address the water pump problem at hand.
Based on the discussion above, it is certain that this mobile tool will aid the water pump operators and engineers to detect specific faults at an earlier stage and address the symptoms of the problems immediately as they appear in order to prevent the problem from occurring which would limit the access to water affecting reliability and availability of water supply.
The displayed screenshots were based on the initial stage of application development, it will be useful to pilot and test it in various regions across the country to enhance its functionality by making the application more interactive while giving room for further improvement. The rate at which users would evaluate this application can improve the rate of its acceptability in the market.
The application development was based on the identified water pump problems; hence further research is required to include several water pump problems. The PDT is a web and mobile-based android application and hence it would be good to include other mobile operating systems for wider applications.
ACKNOWLEDGEMENTS
This study would not have been possible without the internship programme of Building Capacity in Water Engineering for Addressing SDGs in East Africa (CAWESDEA) Project (IDRC Funded Programme; 2018–2021) under Tanzania Water Partnership; my heartfelt thanks go to all organizers. My utmost gratitude goes to my supervisors Dr Subira Munishi and Dr Tulinave Mwamila. Special thanks go to Eng. Anthony Sanga, Permanent Secretary, Ministry of Water for recognition of the contribution of this study in the water sector and offer permission to collect valuable information from the water sector authorities. I also thank RUWASA district and regional managers, Water Resources Department of University of Dar es Salaam and Water Institute Consultancy Bureau for being accommodating during the whole period of research.
DATA AVAILABILITY STATEMENT
All relevant data are included in the paper or its Supplementary Information.
CONFLICT OF INTEREST
The authors declare there is no conflict.