Dozens of jobs could be created under plans to transform the boathouse by Brighouse Marina.
A planning application has been submitted to Calderdale Council to change its use from light engineering.
In its place will be a restaurant, offices, retail and residential units.
Developer Graeme Henderson, of Coley, already has several interested parties.
The vacant site is not a conservation area or Green Belt and has been determined large enough to sustain the proposed mixed use.
A single storey side extension is proposed to replace what was an existing extension.
The Canals and Rivers Trust has viewed the proposals favourably.