Investigating the Potential of Phytoremediation-assisted Treatment of Rainwater for Domestic Use using Selected Agro-wastes as Filter Media

The Bicol Region is one of the most exposed areas to natural disasters in the Philippines. It is economically reliant on agriculture, with coconut and rice among the important crops being produced. This study looks into the potential of utilizing locally available agro-waste materials as sustainable and cost-effective solutions to the artificial scarcity of good quality water from abundant rainwater and stormwater run-off for many disadvantaged communities in the region. Cocopeat (CP) and carbonized rice hull (CRH) were studied as alternative adsorptive materials to sand (S) in the preliminary treatment of rainwater via filtration. Vetiver grass (Chrysopogon zizanioides) and reeds (Phragmites karka) were planted onto cocopeat (CP + Phy) to enhance its filtering performance. The treatment efficacy of the filter materials was determined by comparing the pH, total dissolved solids (TDS), temperature, oxidation reduction potential (ORP), resistivity and salinity of rainwater before and after filtration. Analysis of variance (ANOVA) was used to compare the performance of the filter media tested. The treatment performance of cocopeat is comparable to sand in improving the quality of the tested rainwater samples. Further improvement in the treatment efficiency of cocopeat was observed on some water quality parameters when phytoremediating plants were added.