A State's application to qualify a project under this subpart will include:
    
    
        
        (a) 
         A certification that the bridge is economically desirable and needed as a link in the Federal-aid highway system.
     
    
        
        (b) 
         A statement showing the source and availability of funds to be used in construction of the roadway approaches.
     
    
        
        (c) 
         A statement of any obligation on the part of the agency constructing the dam to provide such bridge or approach roads to satisfy a legal liability incurred independently of this subpart.