Remote disconnect meters have been used in the electric metering industry for at least 15 years. Early adoption of advanced meter  infrastructure and the convenience of endless, on-demand electricity made remote disconnect technology an easy choice for implementation in electric utilities.

But despite sharing the same needs as electric utilities and many additional drivers for adoption, water utilities had to wait for the technology to catch up to their market segment. The technological challenge for water was very clear: lack of constant power.

To implement remote disconnect meters for water, utilities require on-demand, two-way communications to the meter, as well as technology capable of working in a water meter setting for 20 years. Both requirements need efficient use of batteries and robust, long-range communications technologies.

Remote history

In 2009, Mueller Systems released a true two-way AMI system for water: the Mi.Net network. Unlike other AMI systems at the time, it provided on-demand access for full command and control of meters and sensors. Previous networks were essentially only “two-way” in the sense that every meter in the system could maintain time synchronization. However, these networks could not guarantee on-demand, two-way access to every meter around the clock. The Mi.Net network was engineered for on-demand command and requests of each individual meter, which is key for remote connect/disconnect. Much of the value of remote disconnect metering is lost if you cannot ensure valve closures or openings within seconds of the request being made.

While true two-way communication is critical for remote disconnect technology, reliable long-term operational life is key to the meters.   

Mueller Systems designed the 420 RDM (remote disconnect meter) to utilize a proven positive displacement metering technology using a 20-year battery and a nutating disc measurement chamber along with a pilot/diaphragm valve, all within the traditional American Water Works Association 7.5-inch lay length for 5/8-inch and 5/8-by-3/4-inch water meters. This design allows for easy installation with no plumbing alterations or meter box changes. Design engineers performed an intensive search of all valve technologies including ball, gate and butterfly valves. Given the primary requirements of reliable service and long battery life, a pilot/diaphragm valve was selected as the best choice for a remote disconnect meter since it is far more efficient and robust than any other available valve configuration. This design has been tested and proven reliable for decades in irrigation system applications.

The pilot-operated diaphragm valve utilizes system water pressure to allow or stop the flow of water in the meter. When the valve is commanded to actuate, a small solenoid plunger moves, using a tiny amount of mechanical energy, to create a pressure differential by closing or opening the pilot path. This movement either builds or relieves pressure on top of the diaphragm, causing it to open or close the flow of water. The nature of this design offers two huge advantages over other valves: (1) low power requirements and (2) a robust design, making the 420 RDM a true on/off valve.

Full disconnect

Early in the development process of the 420 RDM, Mueller Systems offered a “life-sustaining flow” option. It was thought that utilities would desire a valve “state” that provided a small flow of water in the event of an emergency. Utilities rejected this design for a multitude of reasons and made two strong points:

Utilities’ current business processes involve total disconnection of service (as has been the case for decades), and the move from total to partial disconnection (i.e., life-sustaining flow) creates additional headaches and potential liabilities for the utility.

The low flow of 1/4 gpm to 2 gpm still allows customers to use water at a level that doesn’t give them a strong impetus to pay their bills. For instance, the average low-flow showerhead uses less than 2 gpm, meaning customers on a “trickle” state could still take showers and flush toilets. This could result in an increase in customer debt, the very situation they were hoping to avoid.

By completely disconnecting service, utilities can maintain their current business processes and provide the necessary motivation for delinquent accounts while gaining the efficiencies desired from a remote service disconnect or reconnect.

Based on feedback from utilities that have deployed remote disconnect meters, Mueller Systems developed an improved strategy for situations where customers need access to water to avoid loss of life or negative media called “compassionate scheduling.” Thanks to a valve design that requires little power to operate, the 420 RDM meter allows utilities to schedule water service to come on for only a specific time during the day. Utilities can turn water on or off as they desire or schedule certain time periods automatically. For example, utilities can provide water to a customer who has special needs while still providing the necessary motivation for payment, as well as limiting the amount of debt customers can ring up while “disconnected.”

Reduced callouts

The most obvious use of remote disconnect technology is to shut off and restore water service to customers for nonpayment. For decades, nonpayment has demanded a lot of resources in terms of utility personnel. Typically, the utility would go through a complete billing cycle, and customers who failed to pay the previous cycle would be notified manually (by mail or phone call) with the utility offering a grace period to allow the customers time to pay. After the grace period expired, the utility would then process numerous cumbersome work orders before sending utility personnel into the field to perform a manual shut-off. Ideally, the customer would soon pay their delinquent bill, prompting the utility to again send out personnel to the customer’s home to quickly restore service.

Most important, remote disconnect/reconnect metering technology eliminates the need to send utility personnel into the field to turn service on or off manually. Many utilities disconnect an average of 5% to 10% of their customers each year. For an average utility of 20,000 customers, that amounts to 1,000 to 2,000 callouts per year. With an average callout cost of $50 to $75 each, implementing remote disconnect metering can result in significant savings. Reducing callouts also limits situations where utility employees may encounter risks including unsafe plumbing, unruly customers, aggressive pets or dangerous neighborhoods.

Utilizing Mueller Systems Mi.Host software, utilities can schedule bulk shut-offs in a way that is convenient for handling the customer service implications of dealing with nonpayment. It can also quickly reconnect service while the customer is on the phone. The “wake-on-demand” two-way functionality ensures the disconnect/reconnect command gets to the meter immediately, and the command’s receipt is immediately verified. The software also features alerts that are specific to the meter such as “flow after disconnect” (to detect the unlikely event of a tamper to bypass the valve) and “high flow following a connect,” a handy backup tool to supplement the utility’s business standard operating procedures.

Additionally, there are many situations beyond nonpayment where remote disconnect is an ideal addition to the customer service team’s toolkit. Another pain point for a utility’s customer service is the frequent turnover of customers. The average percentage of households who rent versus own is about 35%, and in some large cities that number is closer to 50%. University towns have high numbers of move ins and move outs, while utilities in the Deep South and Southwest have “snowbird” populations, or Halloween-to-Easter residents. Installing a Mi.Net network and remote disconnect metering helps utilities to eliminate truck rolls in these instances as well.

Customer service is also enhanced through remote disconnect metering. When alarms or alerts appear in Mi.Host — indicating an unexpected excess of flows at certain properties or areas — utility customer service representatives contact customers to determine if the use is valid or possibly the early indication of a leak. This information can be valuable in several scenarios, such as when vacationing homeowners are unaware a pipe has burst. In this case, the utility can shut off service to save precious water resources, avoid large water bills and minimize property damage.

An additional customer service benefit is protection of the public. With remote disconnect technology, the utility can proactively enforce “Do Not Use” orders during a potential contamination event. For instance, if a backflow event has been detected, the system can quickly disconnect all remote disconnect meters to reduce the chance of injury or death by preventing contaminants from reaching the utility’s customers.

With fewer crews and vehicles making routine disconnects and reconnects, utility resources can be redirected elsewhere where maintenance or other work is needed.