Coastlines draw people throughout the history as settlement places presenting softer climate, land fertility, fishing activities, sailing, etc. For this reason, coastal environments are the most affected areas from human activities. Mediterranean coast of Turkey is attracting populations of the same reasons and by the time much more settlements appeared on the coastline. Since, the coastline do not contain much economical and industrial activities, the area turned to inhabit populations for a period of time through the year, mostly summer, in too many seasonal settlements. To hinder wastewaters of these settlements exert high pollution pressure on the coastal environment, current Turkish Water Pollution Control Regulations require the wastewaters to be treated. The treatment systems built and operated in this region are mostly aerobic activated sludge systems, which are known to be poor in seasonal operation. In this study, applicability of anaerobic systems to characteristic coastal settlements of Mediterranean coast is examined by application of both simulated and raw low strength wastewater to an upflow anaerobic filter reactor. The results demonstrated that even low retention times of 6 hrs, 62% COD removal efficiency was obtained from the system, mostly meeting current regulations. It is concluded that fine tuned and well operated anaerobic systems can bear up diluted wastewaters of coastal settlements.