#archived link

As mentioned in my commentary, the hypothesis that the River Running not only runs underneath Erebor, but is also the driving force behind Erebor’s ability to comfortably host potentially tens of thousands of people in architectural splendor as the capital of the Dwarven state is a completely viable one.

Behind every great city, however, is a great waste management system toiling away in the background. The best-made systems, in my experience, are the ones nobody notices - or better yet, double their function as a veritable work of art. In this case, I seek to not only give Erebor’s water system those two functions, but many more.

With the constantly-circulating water this is a closed system that, if designed and maintained correctly, can support multiple uses. Having not only a method of disposal for all waste, but temperature control, electricity production, food supply opportunities, and social spaces in an aesthetically-pleasing manner means that dwarves can expend more effort on doing other things.