In the search for novel and commercially viable utilization of nonwoven fabrics, this study had the objective of determining whether nonwoven mats, which were made from biodegradable natural fibers of cotton and flax, could be used for the adsorption and removal of a ubiquitous pollutant of water and wastewater, namely copper ions. Nonwoven mats were manufactured with various blends of waste cotton and flax and were subsequently treated with citric acid. The treated mats were monitored for copper ion adsorption and fabric strength as compared with the control non-treated mats. The results demonstrate that mats made from 100% flax and 75%/25% flax-cotton blends were similar to each other and were significantly better at copper ion uptake than 50%/50% cotton-flax blends and 100% cotton. Citric acid treatment diminished mat strength as compared to untreated mats for all cotton-flax compositions. The strength values were similar for all treated nonwoven mats after correction for mat thickness. Treated flax fiber mats and cotton-flax fiber mats represent a potentially fast and convenient method for the removal of metal ions from water and wastewater streams.