When Masamune Date constructed Sendai Castle and the castle town, much timber was needed. This timber was obtained from trees felled in Marumori and Kakuda along the Abukuma River. The first part of the Teizan Canal, Kibiki Channel (15 km in length), was built to transport this timber northwards from the mouth of the Abukuma River to Yuriage at the mouth of the Natori River. From there, the timber was transported, against the current, up the Natori River to Minami Zaimoku-cho (literally ‘southern wood-materials quarter’) in Sendai City. Transporting the timber using this method greatly improved the speed of construction of the castle and the city. This was an example of Masamune’s excellent administrative skills.
In order to maintain the water resources for cultivating land for new rice paddies it was very important to control any flooding. Masamune invited Magobei Shigeyoshi Kawamura, an expert from Abu County in Nagatonokuni (present-day Hagi City in Yamaguchi Prefecture, also known as Chōshū). Magobei also provided much help with the building of Kibiki Channel but his greatest achievement was repairing the Kitagami River and establishing Ishinomaki Port at its mouth. Magobei was also involved in the construction of the water course for the Yotsuya water system (just to the north of central Sendai, and now completely submerged under the city), which supplied water to the castle town.
In the middle of the 1600’s, land reclamation progressed and the rice harvest increased. As a result, rice from the northern area was collected at Matsushima. In order to transport this rice safely by boat to the castle town, Ofuna-iri Channel (7 km in length) was excavated from Shiogama Bay to the Nanakita River. Rice and other goods were transported via the Nanakita River to Funadomari (literally ‘boat stop’) in Nigatake Ward of Sendai. Sasaki, Magobei’s son-in-law, was involved in the excavation of Ofuna-iri Channel.