Lock 8 is located in Elmsdale. As with Lock 6 and Lock 7, a weir (a type of dam) was placed across the Shubenacadie River to raise the water level upstream. However, while the two previously mentioned locks were built into bypass channels dug around the weir, Lock 8 was built directly into a gap in the weir itself. As such, it is known as an in-river lock.

Today, the remnants of Lock 8 are barely visible. If you look closely, you can see where the weir would have been, along with the earthen sides of the lock walls. When it was operating, Lock 8 would have resembled Lock 6 or Lock 7.