The Minuma was a large wetland which had been converted into a reservoir during the early Edo Period by the construction of an 870 meter levee between current Tsukishima in Saitama and Kizoro in the city of Kawaguchi. In 1727, the Tokugawa shogunate decided to demolish the levee and to convert the area to new paddy fields. To ensure continual access to irrigational water in the region, an irrigation canal system supplied by the Tone River was introduced. Two canals were dug roughly in a north-to-south direction along the two plateaus that sandwich the region. These canals were separated by roughly a kilometer, with a natural river, the Shiba River, flowing in the valley in the middle. The Minuma Tsūsen-bori was completed in 1731 to connect these two canals, and to thus permit water transport between the new riceland, coastal villages and the metropolis of Edo. The engineer for both projects was
