In general, Automatic Metering Infrastructure (AMI) is no longer thought of as the latest technology to come along. But as AMI technology providers improve their data collection capabilities, water utility managers are making increasingly effective use of AMI data. The result is improved conservation at the utility level as it becomes easier to discover leaks–and help customers save money as the utilities make them increasingly aware of their consumption habits.
In this era of economic contraction, much recent talk surrounds the nation’s aging infrastructure, including water mains in many industrial cities that were built in the early 20th century. Capstone Metering LLC cites research indicating that distribution systems around the world are losing an average of 26% of treated water totaling almost $14 billion in lost revenues. The United States Geologic Survey estimates that 1.7 trillion gallons of water are lost per year, at a national cost of $2.6 billion per year. For developed countries, non-revenue water often represents 20% of the total water withdrawn from the environment. In developing nations, non-revenue water can account for as much as 50% due to distribution system leaks, theft, and poor measurement techniques.
With tax bases shrinking in many communities, reducing non-revenue water loss is not a matter of choice. Increasingly granular and real-time AMI data are making this more realistic.
John Sala, director of marketing for system software and collection hardware for AMI provider Neptune Technology Group, contends that the real difference between automatic meter reading (AMR) technology and AMI is how the data are utilized. He refers to a presentation he has developed in which he describes how multiple generations of AMR technology have produced one output–a bill–and how AMI allows in-depth data analysis and conservation.
The issues holding water utilities back from implementing AMI are technical in nature, according to Sala. While electric utilities invest significant resources in AMI control communications, controlling multiple systems in water AMI is extraordinarily technology-heavy.
“Utility managers understand the business benefits they want, but they don’t necessarily have the technical wherewithal to understand that they cannot automatically start integrating their work order processing because they put an AMI system in place,” he says. “The work order system and AMI need to be talking to each other–that requires them to both interface with each other, and that doesn’t happen by chance.”
Also, the water utility industry lacks a standard communications protocol similar to the electric industry’s MultiSpeak Specification, creating a challenge for communications among water systems, Sala points out.
Despite the challenges, implementing AMI results in improved customer service, says Mike Healy, public works assistant director for the City of Grass Valley, CA, and chair of the American Public Works Association’s Water Resources Management Committee. “The AMI systems of today are a benefit to any and all utilities, and I think the more and more we take advantage of the tools that are out there and are able to see things through the deployment of this system, the sky will be the limit on how we’re going to be able use these management tools to the benefit of our customers,” he says.
Several AMI success stories have emerged in recent years–including in two of America’s largest and oldest cities.
Neptune AMI software reveals operating metrics, consumption, and endpoint locations.
Boston Slashes Non-Revenue Water
In the late 1990s, the Boston Water and Sewer Commission (BWSC) received a $23 million allocation from its board to upgrade about 88,000 meters to radio frequency (RF) technology. This followed a successful pilot study on about 1,400 Aclara STAR Network Meter Transmission Units (MTUs). Combined with STAR Network Data Collector Units (DCUs) and a STAR Network Control Computer, BWSC had the building blocks of an AMI system.
Boston, MA, had utilized meters since around 1900 and, about 30 years ago, made its first foray into AMR by installing remote reading devices outside of homes and buildings. Meter readers took readings from outside, wrote them down, and entered the readings into handheld computers.
“But true automatic meter reading is when you can sit in this building and get readings every day,” says Mark Aigen, meter services director for BWSC, who oversaw the AMI implementation and continues to consult for the commission.
Aigen recalls that many vendors offered solutions that would have allowed an eventual transition from drive-by AMR to AMI. “I think the position of the Commission at the time was: “˜Why should we wait?’ So we went with the fixed network system rather than going to a drive-by.” Aclara’s sister company Hexagram, Honeywell, and ABB teamed up on the implementation.
Mark Medico, BWSC’s deputy superintendent of special projects, recalls that readings were being taken three times a month on approximately 2,000 meters that accounted for about half the water consumption. The remainder were read every other month, and bills were estimated in the in-between month. Jay Porter, chief operating officer for BWSC, says that inbound telephony was tried for transmitting the readings at first, but system maintenance was a problem.
“Eventually, it came down to a customer service decision,” he says, adding that the Internet, which had become publicly available a few years earlier, promised to aid implementation. “We were going to go out and change the meters anyway. We had half a bite of the apple, so we decided that if we were going to change the meters out, we might as well go with the MTUs.”
Among the equipment were 52 DCUs that receive readings from MTUs via cellular technology; the MTUs take readings every six hours. Starting at 9 p.m.–when Verizon gives BWSC free time–the DCUs send the readings to three different computers over a total of 12 phone lines; if one of four lines per computer is busy, the call bounces to another line. Each DCU is programmed with two numbers in case a modem goes down. Each computer uploads the data to an SQL server that parses the data and larger customers receive Web-based consumption reports.
More importantly, customer service representatives have access to reports, including high/low consumption, negative readings, and zero readings. The representatives can compare the past two months to the past seven days, and anything exceeding 200% necessitates a phone call to the customer, who is made aware of a possible leak. Another group performs revenue auditing and analysis and looks for instances of low usage, which might indicate theft of service or a bypass.
“We have more outgoing calls on the customer service side than we have incoming calls,” says Porter, adding that billing errors have been cut by 75% to 80%.
Medico reports that AMI, combined with capital upgrades to its water distribution network, has helped BWSC to cut its non-revenue water from as high as 20%-plus to less than 10% in the past 10 years. Porter adds that BWSC has established “district metering areas” (DMAs) and calculates non-revenue water by subtracting equivalent dwelling units from water consumption for a given DMA every couple of weeks. If the total is above 10% or so, the commission blankets the DMA with leak-detection devices to pinpoint the leak.
Better leak detection has paid off financially, Porter says, referring to a hospital and apartment complex that paid $1 million and $100,000 in catchup bills, respectively. The combination of improved leak detection, more water efficient home appliances, and consumption of bottled water has allowed the commission to reduce water purchases by 26% since 1993. As a result, BWSC has averaged only a 2% rate increase over the past several years, Porter adds.
“All of the information that we’ve been gathering and massaging for 10 years has made us hungrier for even more information,” says Aigen.
Detroit Jumps to Cutting Edge
Detroit, MI, jumped from manual meter reading to AMI, but skipped AMR along the way. Rodney Johnson, Detroit Water and Sewerage Department assistant director, recalls that the city also began a bidding process for AMR system implementation in the late 1990s. After nearly 10 years, though, the AMR initiative was halted.
“Drive-by was our focus at first, but when that request for proposals went out and we received a bid that offered AMI, we found that there were many more things that we could accomplish that we weren’t going to be able to do with drive-by,” he says.
Several vendors claimed that their systems would allow an eventual transition into AMI from AMR, but it would be labor-intensive because a large number of transmitters would have to be replaced anyway. “We couldn’t find a manufacturer who could install a drive-by system and then sort of flip the switch to a fixed network,” adds Johnson.
“At that point, the discussion really became a matter of doing drive-by and being happy with that for 15 or 20 years, or doing a fixed network now and live with that for the next 20 years or so,” he continues. “It took us several years to get through to where we are, which is fixed network.”
Around 2006, the city began implementing Itron’s Water SaveSource AMI system, which is based on high-power, 1-W RF transceivers in the meter endpoints that provide a long-range wireless link between the endpoints and neighborhood collectors, and a redundant star network topology in which meter endpoints and collection devices have multiple communication paths. The system also provides grouping capabilities that allow the utility to compare supervisory control and data acquisition systems (SCADA) information for leak indications, as well as consumer consumption data. To date, the city has gotten about 80% of its roughly 260,000 customers on the system, according to Johnson.
The network currently consists of about 240,000 meters and about 240,000 transmitters. About one collector, that serves as an intermediary between the transmitters and a central meter data management system, is set up per square mile of the city, for a total of about 140, on public buildings such as schools, police stations, fire stations, libraries, public housing, and water facilities. A few other collectors were deployed on billboards and cell towers. Redundancy is built into the system; the system is designed such that every transmitter interfaces with at least two collectors. Every two hours, the collectors transmit meter data to a meter data management (MDM) system that was designed by Hewlett-Packard via cellular technology. The redundant MDM system reads data from a meter via only one collector, though multiple units have collected the meter’s data. The system also sends 25 hourly interval readings and indicates what the readings were for each of the past several hours ago so that if a reading is missed, the city can figure out what the reading should be.
Johnson points out that the city’s water billing system, its Itron Service-Link Mobile Workforce Automation Technology field work-order system, and MDM system are seamlessly connected. The field work-order system informs the billing system when a connection has been made. The billing system informs the MDM system when a reading is required. Customer service representatives can also request on-demand readings from the MDM system.
The city can run several standard reports via the MDM system, such as ones showing which meters emitted tamper alarms. Johnson reports that the city also runs several field work-order reports indicating worker productivity or how many four-hour “window” appointments were missed, for example.
The city uses this information to improve customer service, Johnson says. Without AMI and solid data analysis, “Customers won’t always call you,” he says. “Five may call you, but you still won’t have a good handle on how many appointments are being missed. Is it across the board, and we’re just packing in too much work? Or, is it a problem with a particular crew? Is it a training issue? Whatever it is, we try to track it down to figure out what we need to do so we don’t miss appointments.”
Sometimes a customer will dispute a high reading, and the city uses the interaction as an opportunity to create awareness of a possible leak. “It becomes how well we can figure out what’s going on at a property,” says Johnson. “To me, that’s one of the biggest features of a fixed-network system.”
Johnson concludes that a financial analysis on its AMI system is difficult to conduct because the economic downturn has hit Detroit particularly hard, and its tax base keeps shrinking and adversely affecting the return on investment. Still, the city no longer needs to attend a large number of real estate closings every day to get an accurate final bill, and no longer do at least half of the city’s water bills need to be estimated every month.
Bigger Not Necessarily Needier
Smaller, more rural water districts also benefit from implementing AMI systems. They are more spread out and often require reliable signal transmission over challenging terrain.
Healy’s utility serves about 2,700 customers. The city has begun implementing a Global Water Fathom AMI system. The individual components include T-10 water meters; an Aclara STAR Network Control Computer, STAR Network DCUs, and a STAR Network AMI system; and an Aclara system with Neptune E-Coders.
“What really drove us was aging meter equipment and a desire to get more accountability in our water consumption,” says Healy of the AMI implementation. “We certainly wanted to look at new equipment and opportunities that it presented in the area of conservation and cost containment. From our perspective, confidence and credibility with our customers begins right at the meter. If we can’t intelligently and accurately put out a bill that people have confidence in, we’re not doing right by our customers.”
According to Healy, the system is about 80% implemented. Multiple meter reads per day are allowing the city to determine if customers have a leak and contact them with a notification.
“Later, once the system is fully deployed, we’ll begin to integrate that consumption data into our water purchase profile,” he says. “If we can save on raw water purchases, it certainly will be an advantage.” It will also be possible for the city to benchmark consumption by facility type and build exception reports that indicate to customers how much excessive consumption costs them every month.
Noting that the community is rather hilly and topographically diverse, Healy recalls that Global Water Fathom got the system deployed to operate reliably. The city set an objective of each meter being read by two DCUs with a 99% success rate, which has been achieved so far.
“I think one of the great advantages to having accurate data, which we’ll have through this system, is that it will allow our city council to offer alternatives to the traditional rate structure,” says Healy, adding that a new rate structure might be based on both system capital costs and day-to-day operating costs. “The more you’re able to fairly bill for the cost of water and have an ability to offer your controlling board–in our case, the city council–more options in the way to reach financial sustainability in utilities such as ours, the more it’s an advantage to each and every one of our customers.”
The Chesterfield County Rural Water Company (CCRWC), a privately held nonprofit utility in South Carolina, has about 22,000 residents spread throughout an 800-plus square-mile territory mainly consisting of agricultural and poultry farms and small towns. The territory has rolling terrain with a 700-foot elevation variance, and nearly one-third of it is state and federal wildlife refuge lands. Until 2008, CCRWC used a team of six meter readers who used handheld readers to take monthly readings.
Despite the challenging terrain, CCRWC had compelling reasons to implement an AMI system. The readings and service starts and stops required six trucks to drive six to seven days a month, using a full tank of gas every day.
CCRWC eventually selected the Sensus FlexNet AMI system, which provided it with communications via Federal Communications Commission (FCC)-licensed spectrum and a 20-year battery life on its meters. The system has Primary-Use licensing by the FCC and 2 W of power, suiting CCRWC’s widespread territory and reducing the number of data collectors that otherwise would be needed.
Beginning in August 2008, the AMI system and more than 7,000 water meters were installed. CCRWC partnered with the adjacent towns of Cheraw and Chesterfield for tower placement. The towns allowed CCRWC to use their water tanks for mounting the antennas, and, in return, the two towns were allowed to share the antennas and tower gateway base stations (TGBs). CCRWC leased land from a cooperative landowner to install an antenna and a TGB for coverage of the wildlife refuge areas. There, CCRWC had two monopoles deployed, because a typical tower would not meet wildlife requirements. In all, the network has 14 antennas.
Smart meters equipped with a customer shutoff valve for water were also installed, allowing customers to turn off their own water when necessary, e.g., in the event of a leak. Charlie Gray, chief executive officer of CCRWC, says that the system assists with leak detection. Consumption comparisons are made by 12-hour period. Accounts with a swimming pool, for example, are annotated so that the customer is not notified of a possible leak.
The system has improved the billing process and, thus, customer service. The old system was often delayed by holidays or inclement weather, resulting in a billing cycle that could range from 27 to 35 days. AMI, in contrast, provides a consistent 30-day billing cycle. The system is expected to pay for itself in 13 years. The utility also saves money on fuel and vehicles and has reassigned the meter readers to other positions within the utility. Gray adds that a reduced insurance premium was a pleasant surprise resulting from the implementation.
A Chesterfield County Rural Water Company meter
Conservation at Customer Level
AMI utilization has reached a new plateau where customers are getting access to consumption data and becoming better conservationists.
Porter contends that customer service was not a driving force for technological upgrades 10 years ago or more. Previously, a landlord who owned six properties got six different bills according to which day of the month a reading was taken. Now the city can combine the readings and bill on the same day of the month for all six properties. A single bill reveals to the landlord the overall cost of water consumption, often spurring conservation measures, Porter says. For example, the Boston Housing Authority used to be the city’s largest water customer and has dropped a few spots since receiving consumption reports.
A study in which the Coachella Valley Water District (CVWD) in southern California teamed up with Master Meter indicates that AMI can serve as a key element in reducing water consumption during electrical peak periods in the residential sector. CVWD is participating in the California Time of Use Water Meter Rate Study Project, funded by the California Energy Commission Public Interest Energy Research Program.
CVWD personnel and Master Meter installed meters and the fixed-base AMI system in March and April 2009. In addition, boosters and repeater and concentrator antennas were installed to transmit the interval water use data to the district office. CVWD currently uses the Master Meter Dialog 3G Mobile AMR system for the monthly reading of more than 10,600 water meters. This study required hourly readings as close to the top of each hour as possible. Wireless Meter Interface Units were added to existing meters to allow Dialog 3G meter-integrated radios to forward 15-minute meter reading data and alarms over a proposed fixed-network AMI system. The system is designed to easily migrate to a fixed-network AMI system without losing its mobile AMR capabilities.
CVWD had 148 boosters installed on existing residential single-family detached homes, commercial strip malls, and landscaping irrigation customers in the City of Palm Desert, CA. The use of the boosters allowed quick implementation of the AMI system. A DCU and a field concentrator were installed in an existing CVWD facility in Palm Desert, and antennas were deployed on an existing CVWD tower.
Each of the three customer categories was subdivided into control and intervention groups. Intervention participants were given $25 per month for participating and asked to reduce their water usage during Southern California Edison’s peak period of weekdays from noon to 6 p.m., from June to September 2009. The goal was to determine if peak electricity usage could be favorably impacted by driving down peak water demand through actively sharing consumption information.
Residential peak period water reductions were statistically significant–more than 50%–while business peak period water reductions were not: about 25%. Irrigation did not experience peak-period water reductions.
Smart Grid for Water
Several technological advancements in AMI have emerged in recent years, spurring talk of a “Smart Grid for Water.”
According to Global Water Fathom, the Smart Grid for Water facilitates revenue assurance, responsible water resources management, engaging the consumer in conservation, and water asset management. When deployed pragmatically, the Smart Grid for Water tears down departmental information silos. To be effective, the Smart Grid for Water must integrate AMI, CIS, SCADA, asset management/work order generation and control, GIS, and analytics engines.
Doug McCall, director of business development and marketing at Sensus Metering Systems, notes that Sensus focused on developing a Smart Grid for Water system with FlexNet, which is designed for the unique requirements of water conservation. The system was also designed for true two-way operation; the meters continuously “listen” for firmware updates and on-demand alerts from the utility. Additionally, the system allows control of valves at either the meter level or at the central control level, and customer service representatives can also make on-demand reads. The system also has the capability of providing Smart Grid for Water applications such as pressure equalization, pumping efficiency optimization, emergency shutoff, and early detection for arsenic, according to McCall.
Neptune’s ARB FixedBase AMI system is designed to perform endpoint-level analysis on readings rather backhauling all that data, according to Sala. Prolific readings are also taken every 15 minutes, he adds, increasing the reliability of analysis. Other major components of Neptune’s solution include its N_Sight software application for customer service and a customizable KPI (Key Performance Indicators) dashboard.
Backflow notifications and integrated pressure monitoring are a couple of “smart” functions that the Capstone meter can perform, according to the manufacturer. Pressure monitoring can be particularly beneficial to many utilities that are mandated to maintain a minimum pressure requirement to avoid infrastructure damage, according to Capstone. In addition, pressure correlates with energy consumption. The main idea behind the new meter is to make system operating data available as quickly as possible so that utility managers can promptly discover system problems.
Sala adds a dissenting opinion regarding the existence of a Smart Grid for Water. He believes that the industry will try to achieve system control similar to the electric industry’s system controls. The term and accompanying expectations do “a disservice to the industry,” he says.
Adding valves and sensors to measure water quality or pressure to a water distribution network controlled by an AMI network would greatly increase system complexity, adds Sala. He also says he foresees more SCADA-like capabilities incorporated into AMI. While most utilities understand SCADA systems and their security requirements, they were not yet thinking about the implications to an AMI system when/if starting to use it as a SCADA Lite system.
“One thing that is really agreed upon in the industry is that the cost of water is going to go up exponentially in the future,” he says. “If that happens, the issue of a 20% to 30% system loss is no longer going to be an issue where you shrug and say, “˜Oh, well.'”
As customers see their water cost spike, he adds, the potential for water theft will increase, and security will become a bigger priority. “Analytics and really strong data tools will be required in the water space,” says Sala.
Advice on Successful Use
The managers from Detroit and Boston are bullish on AMI in general but offer insight into successful implementation. “First off, I would tell everybody to do a fixed-network system,” says Johnson. “The advantages are so much greater over a drive-by system. Also, do your homework. Once you settle on one system that you think will do a good job for you, trust that manufacturer. Building in more redundancy increases the cost, but they’ve done this so many times that they know what to do.”
Adds Aigen: “Keep control of your system, because it’s always your system–I’m talking about installation. Don’t let anybody else control it, because once you let it get out of control, it’s very difficult to get back.”
Porter focuses on ensuring the accuracy of consumption data. “Remember the expression GIGO–garbage in, garbage out?” he asks. “It’s all about the data; it’s all about quality control; it’s all about making sure that the data you’re collecting is correct. That was my biggest challenge: to make sure that, during installation, they were at the right address. You can do whatever you want with the data, but it has to be taken accurately.”
But Medico cautions small utilities about implementing AMI without sufficient data-analysis resources. “You definitely need people and the resources to analyze the data to do this. If you don’t have that, you’re wasting the system. If that’s the case–you don’t have the resources–then get a drive-by system and take readings once a month.”
