In 821, he led the work to repair Manno-ike Pond (the largest-in-Japan irrigation pond for farming, located in present Kagawa Prefecture) and led to a successful accomplishment of the work using the latest technology at that time, for example, using arched banks
弘仁12年（821年）、満濃池（まんのういけ、現在の香川県にある日本最大の農業用ため池）の改修を指揮して、アーチ型堤防など当時の最新工法を駆使し工事を成功に導いた。