Water Resources, Sanitation, and Public Health Engineering

Piped water supply systems can be either solar powered water supply systems or gravity flow schemes. We undertake both design and construction of solar powered and gravity flow piped water supply systems. Regarding design, our work includes socio-economic surveys, feasibility studies, preliminary designs, detailed engineering designs, technical specifications, confidential engineer’s cost estimates (BOQ), and tender documentations. In arid areas, we are able to design systems that are wind powered, provided there is availability of sufficient wind speeds. In undertaking feasibility studies and detailed engineering designs for solar powered piped water systems, we undertake surface water hydrological assessments, groundwater assessments, hydro geophysical surveys, water quality testing (for existing boreholes), design of raw water treatment system, pumping mains, distribution mains, electromechanical components, booster pump stations, break pressure tanks, elevated tank towers, and elevated storage reservoir tanks. Our detailed engineering designs are developed using a first principles analysis, ensuring optimal performance, durability, and allowance for easy upgrades, modifications, and water network expansions in future.

We offer consulting and implementation solutions in piped water supply, including but not limited to;

• Feasibility study, detailed engineering design, and construction of piped water supply systems i.e. gravity flow schemes, solar powered systems, and hybrid systems,
• Development of national water resources masterplans,
• Development of district WASH masterplans,
• Development of urban water supply masterplans and strategic plans,
• Development of water safety plans (WSP),
• Rehabilitation of gravity flow schemes and solar powered piped water supply systems,
• Construction and rehabilitation of protected springs,
• Development of operation and maintenance manuals (O&M manuals) for water supply systems,
• Undertaking hydrogeological surveys, borehole siting, and drilling of boreholes and production wells,
• Undertaking of test pumping, borehole motorization, and borehole instrumentation (installation of submersible probes/dataloggers/water level sensors and dip meters),
• Installation of submersible pumps, break pressure tanks, booster pump stations, elevated tank towers, and steel sectional tanks,
• Construction of yard taps, public stand posts (PSP), pump houses, water kiosks, etc,
• Undertaking of borehole fishing and cleaning (borehole flushing),
• Undertaking water quality testing, analysis, and monitoring,
• Undertaking active leakage detection on distribution pipes, water audits, and non-revenue water (water loss management),
• Undertaking water infrastructure rehabilitation and optimal replacement,
• Undertaking high billing investigations, meter tampering, faulty meters, etc,
• Undertaking the laying of pipe extension mains (water lines), as well as pipe relocations and pipeline rehabilitations,
• Installation of fixtures as fire hydrants, service valves, air valves, butterfly valves, gate valves, etc,
• Undertaking of electromechanical works at pump houses and high lift pumping stations,
• Undertaking pressure testing for water transmission mains and for water supply systems for high-rise buildings i.e. hydraulic/hydrostatic and pneumatic pressure testing,
• Construction of sand dams for surface water harvesting, earth dams, water pans, valley tanks, etc,
• Supply of borehole and hand pump spare parts, and drilling accessories,
• Supply of solar water pumping equipment and accessories i.e., solar PV modules/solar panels, solar charge controllers, inverters, batteries, armoured cables, solar panel mounting structures, etc,
• Supply of water distribution system fittings e.g., gate valves, check valves, pressure reducing valves, hot and cold-water meters, mechanical and ultrasonic flow meters, irrigation meters, leak detectors, etc,
• Configuration of surface water and ground water level monitoring stations (analog and telemetric),
• Undertaking electromechanical instrumentation,
• Installation of water distribution pressure management systems,
• Undertaking water audits and water balance studies,
• Undertaking technical and performance assessments for institutional water, sanitation, and hygiene infrastructure facilities,
• Undertaking of water supply infrastructure condition assessments,
• Engineering design and construction of surface intake works, pumping mains, and conventional raw water treatment systems i.e. coagulation and flocculation tanks, air stripping towers, rapid sand filters, slow sand filters, etc.

We supply various equipment, fixtures, and accessories in water supply, including;

• Meter test benches,
• Prepaid smart water meters (with remote billing and shutoff),
• Ultrasonic water meters, pulse meters, hot water meters, industrial bulk meters, residential water meters, etc,
• Gate valves, check valves, butterfly valves, air release valves, non-return valves, diaphragm valves, backflushing valves, flanges,
• Chlorine dosing equipment i.e. inline chlorinators,
• Booster pumps,
• Elevated tower tanks,
• Ground penetrating radars and ground geophones,
• Acoustic leakage detectors and listening sticks,
• Submersible pumps and submersible motors,
• Pipeline trenching machines,
• Pipe threading machines,
• Cast iron pipes, ductile iron pipes, galvanized iron pipes, and mild steel seamless pipes,
• Galvanized steel cold pressed sectional reservoir tanks,
• HDPE butt fusion welding machines,
• Electrofusion welding machines,
• Water bowser trucks/water tanker trucks (including dust suppression water trucks),
• PVC pipes, uPVC pipes, HDPE pipes, PEX pipes, PPR pipes, and PPRC pipes,
• PVC borehole casing pipes, PVC borehole screening pipes, etc,
• SCADA, PLCs, and water quality and quantity monitoring sensors,
• Online real-time water quality monitoring stations with threshold alarms i.e. turbidity, COD, TSS, EC, temperature, pH, etc,
• Water quality testing kits.

Prepaid smart water meters.

These are a revolutionary intervention, for rental, and industrial applications to enable utilities, estates, property owners, and town water boards to avoid water bill arrears. These smart systems are preloaded with tokens purchased using mobile money or online payment systems. The meter remotely cuts off water supply when the tokens are depleted, and restores water supply once recharged. This minimizes the need for door-to-door meter reading and water bill collection, greatly reducing management costs. They enable early tracking and identification of meter tampering through daily consumption uploads, identifying leakages through monitoring inactive user hours, etc.

Water Meter Management.

• Meter selection, testing, calibration, and auditing,
• Installation and management of prepaid water meters,
• Sub-metering in case of multiple users on one master meter i.e., for rentals and plazas including development and management of their billing systems.

Pressure Management Systems.

In water supply systems experiencing high pressures, we undertake the process of identification of high-pressure zones, size, install and offer sustainable pressure management solutions aimed at ensuring reduction in occurrence of bursts, reduction in flow rates of leakages and aversion of new leakages and bursts from occurring. Pressure management is recognized as the foundation for optimal management of piped water supply and distribution systems. It is effective in reducing the frequency of new breaks and the flow rates of those breaks and background leakages that cannot be avoided.

Monitoring pressure in distribution systems.

Pressure management in pipe networks is fundamental to providing safe drinking water. The loss of pressure can allow groundwater to contaminate the distribution system through pathogen entry. Fluctuations in pressure can affect the physical integrity of pipes. Surges in pressure have been known to create additional leaks, main breaks and/or dramatically reduce infrastructure life. Pressure management can also save money. Accurate pressure data allows system operators to reduce leakage volumes, energy costs, system maintenance costs, customer complaints, and water quality problems. We provide simple and cost-effective technologies to continuously monitor pressure in potable water distribution systems. Our pressure sensor, typically installed one per DMA, reports at user-defined intervals via cellular service, helping to identify potential infrastructure failures related to pressure fluctuations that would have led to significant repair costs. Automatic pressure monitoring on an AMI network helps utilities reduce the damage caused by leaks and lowers the chances of burst pipes by allowing operators to quickly reduce pressure when necessary.

Pressure monitoring is especially useful in district metering areas to;

• Perform flow and pressure calculations to show leaks,
• Compute water balance and determine minimum night flow (water balance and water budgets),
• Identify where pressure can be lowered to reduce leaks,
• Control DMA gate valves.

Monitoring pressure to prevent leaks.

Another way to identify leaks and keep a water system operating optimally is through pressure monitoring. Pressure sensors located in the water distribution network can identify anomalies that could indicate leaks or the potential for leaks. Having pressure sensors monitored automatically on a fixed-network increases their effectiveness and efficiency in making pressure adjustments, which helps to minimize occurrences for leakages and pipe bursts. This helps reduce water loss, minimize water main breaks, maintain water quality, minimise risk of water contamination, improve public health, minimize maintenance costs, and extend assets’ lifetime.

Smart Underground Leakage Detection (NRW Equipment).

We have high precision instruments that can be used to detect and locate leakages on underground water transmission pipes. Our smart water leak detectors are highly accurate and sensitive, and as such suited for water leak surveying on plastic pipes. Our equipment digitally locates the leaks on underground pipes, thus enabling utilities to reduce NRW. These systems can detect leaks in pipes buried up to a depth of 1 metre, and are highly sensitive, reliable, accurate, and fast. We deploy accurate, fast, smart, and professional water leak detectors for water leak surveying on plastic pipes like HDPE, PVC, and PE pipes.

Water Safety Plans.

In 2004, the World Health Organization (WHO) introduced water safety plans (WSPs) as an instrument for identification, prevention, and management of contamination risks to water supply systems. The WSP approach is based on the principles and steps of the “Multiple-Barrier” concept for prevention of contamination to water sources and the “Hazard Analysis and Critical Control Points (HACCP)” concept, adopted from food safety management systems. The WSPs are intended to ensure continuous provision of safe water, free from any contamination, for all levels and types of community water supply systems. WSPs have been implemented, mainly by water utilities, in all regions of the world, voluntarily or by regulation.

The WSP approach is systematic, comprehensive, cost-effective and appropriate in a wide range of circumstances and thus are an important tool for community water supply systems.

Water safety plans are widely recognized as the international best practice for guiding reliable and effective management of drinking water supplies to safeguard public health. Recent advancements in water safety planning include;

• Water safety planning for climate resilience,
• Monitoring and control of drinking water quality and supply systems,
• Risk based approaches in drinking water regulation,
• Emergency planning and preparation,
• New and emerging risks,
• Risk evaluation and management,
• Water reclamation and reuse in the context of water and sanitation safety planning,
• Water safety in small systems,
• Water safety plan auditing and implementation.

As such, it is a mandatory requirement by the WHO, water systems meant for communities, health centres, schools MUST incorporate water safety plans. This water quality monitoring requirement believes that “The most effective means of consistently ensuring the safety of a drinking-water supply is through the use of a comprehensive risk assessment and risk management approaches that encompass all steps in water supply from catchment to consumer”. This approach was based on scientific studies that showed that traditional water quality monitoring often produces results which are too little and too late.

• Too little because so few samples are taken compared to the amount of water produced,
• Too late because usually by the time the results are available, the water has been supplied and may have been consumed.

As such, all sections of the water supply plant from water abstraction, treatment, distribution, to the consumer, MUST be critically analysed to foresee likely risks that may compromise the quality of water at each point. These are then graded in terms of magnitude and likelihood of occurrence, and respective mitigation measures that can be implemented to maintain the quality of water, and monitoring guidelines as per HACCP.

In order to guarantee sustainability of the quality of water, it is important to draw up a water safety plan, strictly monitor its implementation, and routinely review and update it. A water safety plan entails compilation of a robust assessment of the likely risks that can compromise the microbial, chemical and physical quality of water, resultantly likely to cause public health concerns from catchment to the consumer chain. Because water supply systems vary greatly from each other in terms of characteristics such as catchment source, types and condition of assets, size, among other aspects, it is important that a specific water safety plan is prepared for each water supply system.

We offer technical support to clients in development of tailor-made water safety plans, to guarantee the sustainability of the quality of water. We enable you to identify, prioritize risks, and ensure appropriate control measures are in place to reduce these risks to an acceptable level.

Our full-line of innovative solutions and services actively diagnose, monitor, and control the delivery of safe, clean drinking water to consumers and businesses.

Non-Revenue Water (NRW) and Water Loss Management.

Water is a fundamental human need, for “water is life.” To ensure that access to safe clean water is brought close to the people, governments and other actors invest in water supply systems (abstraction, treatment, pumping and distribution). These systems’ primary objective is to deliver all the water pumped into the distribution network to the end-user (consumer).

However, it is important to note, like in all systems, there are losses along the pumping-storage-distribution networks. Specifically for water supply systems, the collective name given to these losses is known as Non-Revenue Water.

Non-Revenue Water (NRW) is defined as the difference in quantities of water pumped or introduced into the water distribution systems (case of gravity sources) with the sum of all the water registered by all consumer water meters supplied by that water supply system or all the water billed for that particular month.

What do we mean when we talk about water loss?

Water loss is often referred to as non-revenue water (NRW), water that is produced in a network but never reaches the consumer. This might be due to aging networks which haven’t been properly managed, metering inaccuracies, theft or unmetered authorised consumption, like water used from fire hydrants.

NRW is in other words that quantity of water from which economic benefit is not derived.

In addition to economic factors, there are environmental issues, public health concerns, and requirements in regulations that warrant better management and more effective reduction of water leakage. Controlling network water losses helps curtail drops in water pressure and the associated risk of contamination.

Under our NRW and water loss management solutions, we offer multipronged solutions to address these shortcomings. We deploy high-end NRW equipment and water leak detectors, to accurately detect leaks on any underground water transmission pipes, thus enabling utilities to keep leakage volumes to levels that are acceptable and economically viable (Affordable losses).

We offer technical consultancy aimed to address network losses, leakage detection, network leakage monitoring, billing abnormalities, and water meter management. We offer a complete water loss management plan that involves 4 stages. Firstly, we undertake thorough water audits to ascertain the nature of non-revenue water loss. Secondly, we undertake active location and repair of leaks on water mains and primary distribution pipes. Thirdly, we offer technical advisory on pressure management (based on determination of key locations in the water distribution system that are subject to excessive applied pressure and hence subject to potentially higher levels of leakage, hence advice on installation of pressure reducing valves at such points). Finally, our water audit reports inform infrastructure management such as repair, replacement of water mains, and pumping stations, if very prone to breaks and leaks, and in case such replacement enables cost effective performance of the entire system. From our NRW assessment and water audits, we offer water loss management and reduction plans, advisory on improvement of metering, billing, and collection efficiency, establishment of economic levels of leakage (ELL), pressure reduction and management, analysis and improvement of operations and maintenance, technical trainings and supply of modern NRW technology.

We also implement such methods as district metering areas (DMAs) planning for easy monitoring and tracking of NRW owing to easy analysis of a particular command area, point of leak detection systems, to accurately locate and repair leaks. We deploy non-destructive testing (NDT) technologies to easily locate leakages and bursts on water transmission pipelines such as ground penetrating radars, sonar, and acoustic leak detectors, enabling utilities to reduce NRW to economic leakage levels, generally below 15%. Our interventions enable utilities to effectively identify non-revenue water and devise opportunities to recover uncaptured revenue. Our expert leak detection crews are equipped with proven leak detection tool kits, consisting of acoustic correlators, ground microphones, and noise loggers. These kits allow us to comprehensively survey the water network from above ground. The technology enables faster and more accurate leak detection, which, in turn, helps utilities to better serve their customers, meet legislative and environmental goals and requirements, and ultimately reduce Non-Revenue Water. Additionally, with detailed knowledge of potential leaks and the overall condition of the distribution network, lower operational costs can be expected, and utilities are better able to prioritize investments in maintenance, renovation or even additional capacity.

The technology gives utilities a real-time picture of the condition of their network and lets them easily identify high-risk installations where elevated noise levels indicate possible leaks or bursts. With our next-generation acoustic leak detection technology, potential leaks can be identified proactively before they become larger-scale issues.

Non-revenue water arises due to;

• Meters under registration i.e., inaccurate meters not registering accurately,
• Faulty/defective meters i.e., non-readable and non-working meters,
• Meter tampering,
• Meter reversal,
• Meter bypass and illegal connections (Unauthorized consumption),
• Billing inaccuracies/errors,
• Pressure transients, changing flow rates passing through the water meter, and intermittent water supply in the network,
• Underbilling,
• Pirated connections,
• Leakages, bursts, infiltration, seepages, spills, tank overflows, etc,
• Unregistered and unbilled accounts.

Leakages cause numerous challenges such as;

• Water quality deterioration and health issues,
• Inequitable distribution within a network,
• Increased mains and service connection failures,
• Causes intermittent water supply due to pressure fluctuations. This further leads to water meter malfunctioning and accelerated wear and tear,
• Ineffective supply and demand management,
• Inefficient operations and need for more manpower to locate and fix leakages,
• High coping costs for customers i.e., installation of reservoir tanks, pumps, etc,
• Low revenue collections for the water purveyor/water utility.

Leakage monitoring helps achieve numerous benefits such as;

• Improving water asset management and addressing specific repairs that are needed,
• Maintain consistent water quality,
• Reduce customer complaints,
• Lower operational costs,
• Comply with UNBS/MWE/WHO drinking water supply standards,
• Lower operational costs,
• Preserve dissolved oxygen,
• Improve public health,
• Reduce non-revenue water,
• Identify leaks, manage repairs, and effect proactive repairs,
• Prioritize repairs and replacements,
• Optimize capital plans i.e., aging infrastructure planning and capital improvement plans (CIPs),
• Mitigate failures,
• Reduce leak run time, reduce water loss, and improve water supply network efficiency,
• NRW reduction means increase in revenue for water utilities,
• Maximize network efficiencies,
• Increase in knowledge about utility assets,
• Timely and accurate reporting,
• Reduces risk of consequence of failure.

Under our water loss management program, we offer the following;

• Supply of acoustic leakage detection (ALD) equipment,
• NRW assessment and strategy design,
• Preparation of NRW reduction strategic masterplans,
• Network zoning and DMA design,
• Pressure management,
• Asset management plans,
• Smart water networks i.e., remote leakage and pressure monitoring sensors,
• Meter testing i.e., ultrasonic meters,
• Preparation of water efficiency plans,
• Water audits, including current use practice and identification of wastage,
• Operations and maintenance plans,
• Water balance studies,
• Leak detection and repair of underground pipes, including updating of plans,
• Leak location and repair on consumer plumbing,
• Engineering design and installation of water-saving devices,
• Engineering design and implementation of pressure control devices,
• Consumer meter evaluation for accuracy,
• Flow and pressure measurements before and after corrective measures,
• Revenue enhancement: consumer meter analyses, meter revenue analyses, meter audits,
• System stabilisation, ensuring that entire reticulation networks remain pressurised 100% of the time,
• Condition surveys of meters and valves i.e., condition surveys, testing, and calibration of bulk and district water meters,
• Water system operations i.e., training of operations staff, operations and maintenance plans and manuals,
• Optimal zoning of water distribution systems i.e., review of DMA’s (district metered areas) and pressure zones, including supply zone isolation checks,
• Leakage management i.e., datalogging, site inspections of visible leaks, step testing of DMA’s, leak detection of buried leaks using leak noise correlators and geophones,
• Technical advice on innovative and cost-efficient network monitoring systems according to the individual framework conditions of your supply system,
• Technical training to increase the NRW know-how in your water utility or WASH organization by means of individual training programmes.

Rationale for water loss control programs.

Around the world an equivalent of about 39 billion dollars a year of non-billed water is lost, with a percentage of losses globally between 20 and 50%., Volumes that can be traced back to various factors, including certainly physical causes such as breakages or unauthorized consumption. To try to avoid such consequences, it is necessary to provide for the efficiency of the networks by protecting the system from pressures that can lead to accelerated aging. While most water utilities install and maintain domestic water meters, in most utilities customer meters are replaced on a run-to-fail basis, since in many countries there is not yet a mandatory requirement to replace the water meters. As a consequence, residential water meters are quite old and inaccurate.

Water supply system management has to be based on a deep knowledge of its cost, of the network water and energy consumption and of the level of water losses. Every leakage control program has a water system balance as a common starting point.

The importance of leak detection is not limited to concerns about water scarcity alone. It also entails the financial stresses on water utility rates and budgets related to aging infrastructure and the unfunded treatment costs for every wasted gallon. The double-edged sword of water loss is that, for every gallon lost, the utility receives zero income to pay for salaries or infrastructure maintenance. On top of that, it must still fund the energy and chemical costs to pump and treat it.

Payments for damages to private property as a result of water main breaks are another potential out-of-pocket cost. Insurance might cover certain amounts, but self-insurance and higher premiums for repeat occurrences can eventually exceed the cost of a leak detection investment.

Increased repair complexity for leaks that escalate in severity, potentially becoming sinkholes before being discovered, typically incurs elevated component and labour costs. In extreme cases, that can include heavy equipment rental, more extensive traffic control, and perhaps penalties for disrupting major traffic routes or critical infrastructure such as hospitals or schools. This is what merits investment into water loss control, to maintain leaks within globally accepted economic levels of leakage. It also helps utilities satisfy/comply with regulatory mandates for water conservation.

The multi-step water loss control involves the following steps;

• Perform a water audit, or water balance, to account for all metered and nonmetered water use. A properly done water audit gives the information needed to calculate non-revenue losses,
• Do a component analysis to determine where failed pipes or inaccurate meters are located. Having good data allows identify bad components and prioritize them for repair,
• Develop an intervention strategy for repairing leaks. Setting up district metering areas, or DMAs, is one intervention strategy that makes it easier to identify abnormal consumption. DMAs are hydraulically separated areas within a distribution system and a valuable tool for combating NRW. This typically involves the installation of some boundary valves and a master meter to measure the inflow to the area, then comparing the inflow to the total reading of the meters. In most cases, there is some preliminary work necessary to determine the accuracy of meters in that area. This provides a better understanding of the split between NRW due to leaks versus that due to meter inaccuracies.

In our NRW advisory and training, we undertake the following;

• We analyse your water losses and advise on proper non-revenue water management strategy using the most advanced software tools (water balance),
• We design and implement pressure management zones (PMZ) and district metered areas (DMA) and support leakage reduction by choosing appropriate leak detection technology and repair strategies,
• We support the optimisation of your failure documentation and failure statistics and develop an appropriate database for maintenance planning,
• We support utilities to operate at the optimum level for energy efficiency, pumping efficiency and pressure management, including the monitoring and elimination of pressure transients by high-speed continuous pressure transient measurement,
• We support the optimisation of pressure in your system reducing leakages, burst frequency and energy costs. We help you to implement advanced pressure management (PM), a fundamental activity for water loss reduction and improved asset management,
• We analyse the efficiency of your customer meters and assist you to define an economic replacement plan to increase revenue and improve your level of service.