Explain how the 'C' factor in the Hazen-Williams formula is affected by the age and material of a PVC irrigation pipe, and how does this affect pressure loss calculations?

The 'C' factor in the Hazen-Williams formula is a coefficient representing the roughness of the interior of a pipe. It directly impacts pressure loss calculations, with a higher 'C' value indicating a smoother pipe and less friction, while a lower 'C' value indicates a rougher pipe and more friction. For PVC (Polyvinyl Chloride) irrigation pipes, the 'C' factor is affected by both the age of the pipe and, to a lesser extent, the specific material formulation. When new, PVC pipes typically have a high 'C' factor, often around 150. This high value reflects the smooth internal surface of new PVC, minimizing friction and pressure loss. However, as a PVC pipe ....