Why is there a narrow piece of coping under my raised beam?

The narrow piece of coping under your raised beam is called a finger ledge. This feature is specifically designed to provide swimmers with a safe place to grab onto the side of the pool for support, especially in areas where there are no immediate egress points (like steps or ladders).

The finger ledge is an important safety feature of your pool, ensuring that swimmers can easily regain balance or assist themselves in getting out of the pool when needed. It enhances pool safety by offering an additional means of support.