Regarding environmental impacts, for groundwater, AgNP CWF technology exhibited the lowest overall GWP, estimated to be 0.04 [0.03 -0.07] kg CO2 eq•cap -1 •yr -1 , which was followed by POU chlorination with had an estimated GWP of 0.12 [0.07 -0.28] kg CO2 eq•cap -1 •yr -1 (Figure ). The UV LED had a higher GWP of 1.51 [0.84 -3.49] kg CO2 eq•cap -1 •yr -1 , while the UV mercury lamp technology had the highest GWP, estimated at 2.55 [1.50 -5.29] kg CO2 eq•cap -1 •yr -1 . For both UV systems, the impact on GWP from capital materials was greater than that from operation and maintenance, which mainly consisted of electricity consumption and lamp replacement. However, the POU chlorination system was also influenced by operation and maintenance costs due to the need for consumable NaClO.