Every water system needs data to make decisions about day-to-day operations and long-term strategic planning. Unfortunately — whether due to cost or practical limitations — not every one of them has access to all the data they would like to make the most productive decisions. Here are several ways that even smaller utilities can implement affordable technologies to improve visibility into what’s happening in key areas of their systems.

Widespread Problems, Focused Needs

The top two concerns listed in the AWWA 2021 Executive Report on the State Of The Water Industry are aging infrastructure and capital improvements. But why are data management and water loss control only ranked 19^th and 20^th respectively when non-revenue-water (NRW) losses associated with aging infrastructure are pretty much a universal problem? Without the ability to document how much water is escaping from which areas of the system, it is difficult for top-tier decision-makers to estimate the true economic level of leakage (ELL) and implement cost-effective remedies.

Water distribution utilities that already use district metered areas (DMAs) to monitor water loss have built-in opportunities to pinpoint problematic areas in time to take cost-effective remedial action. Fortunately, those that are not yet set up for full-fledged DMA monitoring now have the opportunity to use select job-matched instruments and Internet of Things (IoT) technology to gain better insights into distribution system operations without excessive expense. Consider the following reasons and affordable options for reconciling the multiple interrelated concerns cited above.

Five Key Reasons To Advocate For Smart Water Solutions

When does the situation warrant an investment in a smart water system for a small water distribution utility? Wherever the location or volume of water losses are unknown, better data collected through smart water sensors and IoT capabilities can be key to better decision-making. Consider how select, affordable investments in precise measurement and near-real-time data access can pay big dividends in terms of reducing NRW losses and extending infrastructure longevity across these key areas of concern:

• Identify Surprise Leaks. Whether it’s the cost of undetected underground NRW leaks or the glare of public reaction to frequent, obvious above-ground leaks and repairs — especially in areas struggling with water scarcity — having early-warning signs to evaluate and manage those leaks is critical.

• Practice Water Infrastructure Triage. Knowing where to concentrate limited funding for repairs in worst-case areas of aging infrastructure can help leverage the greatest payback from limited funds.

• Protect Fragile, Aging Infrastructure. Balancing distribution system pressure levels against actual flow demands in areas of aging infrastructure can help to reduce operating pressures to ideal levels, thereby relieving pressure on the system without compromising service levels at end-user locations.

• Pinpoint Monitoring Locations. The International Water Association (IWA) Water Loss Task Force advocates the use of DMAs for active leakage control (ALC) in order to understand system function and identify where leaks are occurring. Smaller utilities might only need to focus on select pumping stations, takeoffs from a primary water main, or sections of aging infrastructure where suspected water losses cannot be quantified.

• Find Attractive Alternatives For Retrofit Applications. Common justifications for ignoring DMAs or zone pressure monitoring are the perceived costs and inconveniences of trying to retrofit new instrumentation into existing infrastructure. Fortunately, instruments that can be hot-tap mounted in tight quarters and can access affordable and readily available IoT communications options to transmit sensor data to central data management control systems are now making such retrofit conditions more practical.

Aim Big, Target Small

So much attention has been focused on the big-picture concept of smart water that it can easily intimidate smaller water utilities. IoT data collection and connectivity, data analysis, artificial intelligence, and Big Data offer a lot of promise in terms of combating water losses. But the root of any solution still comes down to obtaining accurate readings at specific areas of concern, as described in this downloadable document. That starts with choosing the right instruments and installing them in appropriate locations to yield accurate real-time readings.

Unfortunately, the cost and complexity of installing conventional full-bore flow meters in key distribution system locations can be compounded by a variety of factors — tight spacing; turbulence-inducing valves, fittings, and elbows; or even just the inability or unwillingness to shut down the system for installation.

Yet, even the smallest utilities can be successful in leveraging zone-specific flow data for a holistic view of their water distribution operations simply by targeting their most critical data needs and not being intimidated by perceived structural or installation concerns, as described in the examples below.

Multiple Choices For Easy, Accurate, And Cost-Effective Installation

Whether a water distribution system already has IoT infrastructure to collect and manage data or not, the first step to getting data for better informed decisions on water system operations is accurate measurement at strategic locations throughout the distribution network. Here are some key guidelines that differentiate practical, affordable solutions for small to midsize community water systems from misconceptions about overly expensive and hard-to-implement smart water solutions:

• The Importance Of Documenting Flow. The cost and complexity of DMA capabilities can vary based on the size of the water main and whether precise instrumentation is being incorporated as part of a new infrastructure installation or being retrofit into an older system. Being able to document flow entering and exiting a DMA and comparing those totals to water billed to all customers in that area makes it easy to subtract one flow from the other to calculate water loss. Doing so on a regular basis, often during overnight hours, can make it easy to spot abrupt changes in base flow levels that might indicate the start of a new leak within the confined area of the DMA.

• New Installations. For example, flanged, full-bore electromagnetic (mag) meters (Figure 1) available in sizes from 4” to 48” offer + 0.5 percent accuracy and job-matched capabilities for new or rebuilt flanged piping infrastructure. They can function accurately even when positioned as close as zero pipe diameters from downstream flow disruptions and just one pipe diameter from upstream flow disturbances — e.g., elbows, pumps, partially opened valves, or changes in pipe size.

Figure 1. Full-bore mag meters use compact, high-density magnetic coils to generate an electromagnetic field inside the pipe section. Voltage generated by movement of conductive liquid flowing through the pipe is measured by electrodes inside the meter and converted to a flow rate reading that can be transmitted to a central database. This technology provides high accuracy despite potential mounting locations with turbulent flow generated from nearby elbows, valves, or pipeline restrictions.

Figure 2. A full-profile insertion mag meter with multiple sensors along the length of its probe can provide the accuracy of a full-bore mag meter without requiring the system to be shut down and dewatered for installation. Designed for installation through a hot-tapped ball valve, it can save up to 45 percent of the costs demanded by conventional full-bore mag meters in retrofit applications.

• Retrofit Installations. For retrofit installations in existing infrastructure, a full-profile insertion mag meter (Figure 2) offers the same + 0.5 percent accuracy, but with hot-tap convenience that eliminates the need to disrupt operations. This design can be installed in tight spaces, without the cost of heavy equipment or the need to shut down and dewater distribution system lines. It can deliver up to 45 percent savings on installation costs and total costs of ownership. This Q&A article outlines its most advantageous characteristics for DMA applications.

With multiple water flow sensing electrodes mounted in a long 316-SS probe that can span the width of any pipe diameter from 4” to 138”, this design provides accurate reads even when positioned close to flow-disrupting constructions. It installs into a 2”-diameter ball valve that can be hot-tapped virtually anywhere into an existing pipe. With appropriate customer input, the ideal placement can be modeled using computational fluid dynamics (CFD), taking into account flow rates and the conditions of the piping infrastructure (Figure 3).

Figure 3. Proper positioning of flow meters can be critical for optimal measurement accuracy, even with disturbance-tolerant mag meters. As these two computational fluid dynamics (CFD) diagrams show, the turbulence generated by one inflow line (top) and that generated by four inflow lines (bottom) behave differently at different locations along the manifold. Working with a supplier experienced in CFD analysis can help to pinpoint the ideal locations for monitoring distribution system flows.

• The Importance Of Managing Pressure. Even when flow is being accurately measured at each customer water meter and at key junctures throughout the transmission infrastructure, pressure monitoring is yet another factor that goes hand-in hand with reducing the volume of NRW leaks and protecting the remaining life of aging infrastructure.

For example, maintaining unnecessarily high water pressures will force more water through existing leaks and can create a greater risk of damaging already fragile piping connections. Strategies can include reducing pressures during overnight periods of low demand or using pressure control valves to limit high-pressure pumping to only those zones that experience changing elevations in the natural topography or to only those times when higher pressure is needed to fill water storage towers or reservoirs.

Managing the ideal balance between flow and pressure according to specific demands and operating conditions can also optimize pumping energy consumption as well. The right pressure-monitoring sensor can also help to identify the source of transient pressure spikes associated with water hammer conditions.

• Look For Built-In IoT Compatibility. For convenient data collection and transmission, look for flow and pressure instruments that provide smart outputs for compatibility with industry-standard advanced metering infrastructure in IoT networks — such as popular Sensus and Itron communications protocols.

Use More Detailed Data To Support More Holistic Solutions

Balancing both flow and pressure, based on real-time data, helps utilities reduce stress on damaged or aging systems, improve the efficiency of the water distribution system operations, and minimize NRW losses — all without compromising customer satisfaction. This case study of a 16,000-customer water utility in a mountainous area shows the ease and benefit of retrofitting an existing distribution system with accurate flow meters to maximize declining water resources — without having to disrupt or dewater the distribution system.

While many small utilities cannot afford to monitor every junction throughout their distribution systems, working closely with instrumentation providers can help them with strategic positioning of flow and pressure sensors to provide a more holistic and timely view of system operations. Taking a step-by-step retrofit approach can help the savings from early investments at the most critical locations pay for subsequent investments in other challenged areas of the infrastructure.