Abstract: This invention relates to a transportable modular container system for fluid freight. The transportable modular container system comprises a container module including a reservoir configured to hold a fluid; an adjustable support for the container module, removably securable to a load area of a freight carrying transport and reciprocatingly adjustable between proximate and distal positions, the container module being located relatively closer to the load area in the proximate position than in the distal position, and wherein a zone for secondary freight is defined between the container module and the load area when the adjustable support is in the distal position and removably secured to the load area of the freight carrying transport; and a removable fluid flow control module for controlling fluid flow of the fluid between an external reservoir and the container module reservoir and releasably connectable to the container module.