Where is the most common location of leaks on old service connections?

The most common location of leaks on old service connections is typically where connections are made to the curb stop. This is because curb stops are often subjected to environmental stresses, such as ground shifting, freezing and thawing cycles, and corrosion over time. Additionally, the materials used in older service connections, which may not have the same durability as modern materials, can deteriorate at the points where they connect to the curb stop. This makes these areas particularly vulnerable to leaks.

In contrast, connections to the mainline are generally designed to be robust and are maintained more rigorously, while connections at the treatment facility are usually not as prone to leaks due to the nature of their installation. Connections at the house service may also experience leaks, but they are often less frequent compared to those at the curb stop since they are more accessible and more regularly monitored by homeowners. Thus, the unique combination of environmental factors and material wear and tear makes the connection to the curb stop the most common source of leaks in older service connections.