The Reynolds-averaged Navier-Stokes (RANS) equations were solved to model flow through two aged pipes at Reynolds numbers ranging from 6,700 to 31,000. Turbulence models employed include the ��2-��, realizable ��-��, and k-ω models. The ��2-�� turbulence model was found to more accurately reproduce available experimental results compared to the ��-ε and k-ω turbulence models for flows at ��=13,000 and R=31,000, while the realizable k-ε model was most accurate at R=6,700. Much of the error is likely attributable to deficiencies in modeling complex flow structures with flow separation and wall roughness elements smaller than the grid scale.