Injection wells provide a safe, economical, and effective means of recharging substantial quantities of waste water to the ground water supply. However, the problem of major importance in connection with injection well recharge is the clogging of the soil pores at the soil and water injection interface and in the soil in the immediate vicinity of the injection well. Two clogging factors, physical and biological, were observed after recharge of either fresh water or filtered secondary treated sewage effluent. Both clogging processes took place at the same time during injection. Experimentation with combination beds of sand and anthracite, sand, anthracite and carbon, and single beds of sand or anthracite led to the choice of anthrafilt filter media as producing the longest filter runs and the best effluent quality.