Dimensional analysis of the Froude Number

[Timburton91]

Homework Statement

Dimensional analyse the Froude Number (fr) = Velocity (u)/Accerlation due to gravity (g) * Hydraulic depth (D)

Relevant Equations

fr=u/g*D

So, I have calculated that to dimmensional analyse this equation;

 

[Office_Shredder]

D is hydraulic depth, not density. I think it has different units?

Also, isn't there a square root in this equation?