The present invention provides a water-based coating system that can be used to form durable, abrasion resistant, corrosion resistant, protective barriers on a wide range of substrates. The coating system is particularly effective for protecting metal-containing substrates, such as intermodal cargo containers, against corrosion. As an overview, the present invention provides water-based primer compositions suitable to form primer coats and topcoats on substrates. Desirably, the primer incorporates one or more chlorinated resins for excellent corrosion protection. These polymers not only provide excellent corrosion protection and but also show excellent adhesion to a wide range of substrate materials. The system also includes topcoat compositions enhance compatibility and adhesion to the primer and to provide enhanced application.