The goal of this research paper was to develop practical guidelines for the design and operation of conventional water treatment plant filters to maximize particulate removal while optimizing biological removal of biodegradable organic compounds. The experimental investigations were conducted at demonstration- and full-scale, with supporting bench-scale and modeling work. Major factors investigated included choice of media (GAC vs. non-adsorbent media), contact time, temperature, backwashing strategies and the presence of oxidants in filter influents. The modeling used a practically oriented, fundamentally based model that addressed the non-steady state nature of biofilters.