h i g h l i g h t s RSM was performed by a three-factor, two-level central composite design for PCPC. Compressive strength and void content of PCPC ranged 2.5-13.5 MPa and 12-22%. ENP Fe-surf had a positive but the least effect on the compressive strength of PCPC. Optimum PCPC ratios were at 0.34 W/B, 0.15 FA/B and 0.05 ENP/B. P removal by optimum PCPC was at K f of 2.48 mg 1À1/n kg À1 L 1/n and 1/n of 1.7. a b s t r a c tResponse surface methodology by a two-level central composite design optimized the ratios of water-to-binder (W/B), fly ash-to-binder (FA/B) and iron oxide nanoparticles-to-binder (ENP/B) for Portland cement pervious concrete (PCPC). Compressive strength, permeability, void content and density ranged 2.5-13.5 MPa, 5.3-17.4 mm/s, 12-22% and 2120-2360 kg/m 3 , respectively. W/B and FA/B had significant impacts on all the PCPC properties, whereas ENP/B produced significance only for the compressive strength. PCPC was optimized with 0.35 W/B, 0.15 FA/B and 0.05 ENP/B. The optimized PCPC exhibited enhanced phosphorus removal with the first-order removal constant at 0.031 h À1 and the Freundlich isotherm constant at 2.48 mg 1À1/n kg À1 L 1/n .