RE:oil & gas pipeline construction costs per wikipediaif drilling produces hydrocarbons in commercial quantities, it likely will be productive in a progressive manner (start small, grow larger) over a period of years. a smaller pipeline(s) may be sufficient in the early years. later, larger lines may become appropriate, or multiple lines serving various sectors of the basin. it is waaaaay too early to be planning pipeline sizes and routes.
the permian basin in texas is served by multiple oil and gas pipelines. the network evolved over decades, dictated by logistical needs as they developed.
i expect this to hold true in namibia - if and when.