GAD Plumbing & Heating GAD Plumbing & Heating has been proudly serving the community since 1980. Our family owned and operated business specializes in plumbing services, well pumps, water treatment, home & pier winterizing and remodeling services. GAD Plumbing offers scheduled week day and 24/7 emergency plumbing service in Anne Arundel, Calvert, and Prince George’s Counties. If you are in need of a plumbing repair, or you need an estimate on a water treatment system or plumbing remodel, our team of dedicated experts are standing by to assist you.