This building contains the boundary marker for the angle in the boundary between Bristol and Norfolk Counties. So, it should lie on the County boundary marked on this map. But the two features are offset in this rendering. (~100 meters)

This change may fall under the category described here:
waterway=riverbank
Mixing of types can cause challenges.

Tried to add it as a source for Eagleville Lake but still learning how to connect features.

The segment from the cultivated field at the East end of this trace to Bigelow Brook is mostly deciduous forest. So it is possible to use 'natural hillshade' to detect the old road. But tree cover between Bigelow Brook and the Natchaug Trail makes it difficult to see the trace. May need to find an alternative and remap with better information.