I recently published a report for the New Jersey Department of Environmental Protection (NJDEP) on. The NJDEP commissioned this report to support future improvements to the New Jersey Statewide Water Supply Plan. As part of this project, I assessed the "nonrevenue water" of the water utilities that serve New Jersey. Nonrevenue water includes real water losses, the water leakage from utility pipelines and customer service lines (the smaller lines from the curb to the building that are owned by the property owners, not the utilities). Nonrevenue water also includes legitimate uses that are not metered, such as firefighting, and apparent losses caused by problems with meters, billing systems, and the like. In New Jersey, roughly 80 percent of nonrevenue water is real water losses.
The results show that we have many utilities with low rates of nonrevenue water, at less than five percent or 10 percent, which means that they have low real-water losses as well. However, there also are many utilities with much higher levels of nonrevenue water, including some with over 40 percent or 50 percent. Statewide, our estimate of total nonrevenue water from all New Jersey water utilities is an average of 190 million gallons per day (MGD), or nearly 20 percent of total water produced, and roughly 160 MGD of that are real losses to leakage, where water put into the system never makes it to a legitimate use. That is too high.
High water losses are a concern for several reasons. First, they mean that excess water is being withdrawn from reservoirs, rivers, and aquifers (ground water), which places a stress on those water resources. During a bad drought, high water losses can make the difference between limited and draconian restrictions on water uses. Water losses are the hardest water "use" to control, which means that reducing them now is important for surviving a major future drought.
Second, high water losses are a financial loss to the water utilities. Good, clean water is being put into the system but not getting to a customer. The result is that the costs of acquiring, treating, and delivering that water are wasted, increasing the water rates for everyone.
Third, high water losses are a good indicator that a water utility is poorly operated, with insufficient maintenance, repair, rehabilitation, and replacement of its distribution system. Customer-service lines can also contribute a great deal to water losses, but if a utility has no way to identify and track these losses, nothing can be done. A well-managed system has lower water losses. It is that simple.
We should all recognize that it is impossible and incredibly expensive to achieve zero losses. It doesn't make sense economically or from an engineering perspective. Given miles of pipes, there will be leaks. The concern is whether the leakage is excessive. We also need to know whether the water losses are increasing or decreasing.
Our research used nonrevenue water information for 228 water utilities compiled by the NJDEP and the Delaware River Basin Commission, including all but four of the 59 utilities with average demands of more than 3 MGD. In both cases, the primary information available was nonrevenue water as a percentage of total water produced. We know that a single percentage threshold is not appropriate for regulatory purposes. Water utilities differ regarding the types of customers (all residential to heavily industrial), the number of customers per miles of pipeline, the topography of the service area (flat versus lots of hills), and so on. Each will have a different optimum water loss rate. However, the percentage of nonrevenue water provides an initial basis for analysis and planning.
Perhaps the most important finding is that on average, utilities in northern New Jersey have water losses much higher than similar utilities in the coastal geology of southern New Jersey. The north Jersey rates are roughly double. That makes some sense, as the coastal systems are in flat areas and therefore don't need high pressure to push water up hills, and on average they are newer. North Jersey systems often are in hilly areas and include many of our oldest urban and suburban centers.
The other major finding is that many utilities do much better. In South Jersey, nonrevenue water rates of roughly 5 percent have been achieved by a quarter of large, medium, and small utilities. For north Jersey, the most efficient quarter of large, medium, and small utilities achieve roughly 15 percent, 10 percent, and 12 percent nonrevenue water, respectively. Even though optimum rates for each utility will differ, these findings tell me that we could do a much better job of limiting water losses. After all, 5 percent of all New Jersey's public water demands is roughly 50 million gallons per day. That is nearly equal to Newark's average daily demand.
Now we get to the difficult question: who is responsible for achieving these better results? Water utilities can and should be responsible for reducing leaks in their pipelines, and the 2017 Water Quality Accountability Act will drive them in that direction. The NJDEP will need to change its approach to water losses, using improved loss-accounting methods that have been developed by the American Water Works Association and the International Water Association. The NJDEP will also need to move from a single threshold for water losses to an approach that reflects the realities of north/south differences, plus the fact that some water resources are more stressed (and therefore should be more carefully managed) than others.
However, utility customers also have a role to play, as they own the millions of service lines that go from utility pipelines to their buildings. Water meters are in the buildings, and so leaks in the service lines aren't detected by those meters. We will need a partnership between the utilities, which can employ improved detection methods for water leaks, and the customers who own the service lines. We may need to include a forcing mechanism to gain customer involvement. After all, if their line is leaking, all customers pay for that waste. Therefore, property owners should protect the interests of all customers. Our system of law does not currently include a responsibility for "good housekeeping" on the part of property owners.
There is an interesting implication to this research. The more we know, the easier it is to justify taking focused action, but the harder it is to apply "one size fits all" regulatory requirements to the problem. We need to be more sophisticated about how we manage our water resources, without making the system so complex that it becomes unmanageable.