The report includes a high level summary of the conceptual design of Water Prism, and walks the reader through the major steps of a Water Prism analysis. The report explains in detail the calculations for free flowing rivers, impoundments and rivers below impoundments, and groundwater. The report summarizes the calculation and representation of environmental flows in Water Prism, and discusses future development tasks planned to increase the functionality and applicability of Water Prism to other systems.