Derek is a proud Waterloo resident and has been serving his neighbors with best plumbing practices for the last 20 years. Williams plumbing LLC is new but the owner is not. As a licensed certified master plumber Derek can and will handle any job or problem you may have. If you have a quote from another plumber and you want a second opinion give Williams Plumbing a call. Serving Waterloo, Cedar Falls, and the surrounding areas. Service & Repair New Installations Remodels Bathrooms Kitchens Leak detection Water Heaters-service, repair, and installation Residential Commercial Call today for the service you deserve.