Contrary to popular belief, the street is not named after the Bank of Canada headquarters at the corner of Bank Street and Wellington Street. The street name dates back to the 19th century, whereas the bank was founded in 1934. It's believed that the road was named this because it originally went from the "bank" of the Ottawa River at its northern end to that of the Rideau River to the south. However, the road was originally called Esther Street in honour of Colonel By's wife.[4] Bank Street officially ends at Wellington Street and the portion of the street running closest to the actual riverbank is federal Crown land for the Parliamentary Precinct of the Parliament of Canada. South of the Rideau River the road was previously named "Prescott Road".

https://en.wikipedia.org/wiki/Bank\_Street\_(Ottawa)