In this study, PET spunbonded nonwoven geotextiles were used as filter media of PVD(Prefabricated Vertical Drainboard). 3.5% NaCl solution as an artificial seawater was applied to examine the long-term strength retention and reduction factor was determined from strength retention. Arrhenius models is applied to evaluate sustainable applicability of PET spunbonded nonwoven geotextiles at 25℃ is predicted.