The dispute over the construction of Tianhu Embankment on Dongting Lake in the 1930s and 1940s was among the most serious irrigation disputes in Republican- era Hunan. It reveals conflicts among different interest groups in Hunan and between Hunan and Hubei, and also illustrates the relationship between the provincial and central governments. This article re- examines the dispute and argues that what appear to be the agricultural interests in the dispute were actually inseparable from fishery interests. Investors in the Tianhu project, who were mostly fishery owners, claimed that the project would ＂contribute to agricultural development＂, an official discourse that helped them strengthen and legitimize their status in local society. Other involved parties who had ownership rights over lake waters claimed to be managers of modem fishery enterprises or to be representing local residents. They thus took on an identity as residents of the land surrounding the lake, and similarly sought benefits under the pretext of pursuing agricultural development. Hence even as their economic interests shifted to fishing during the agricultural recession of the 1930s, investors in the Tianhu embankment project continued to adopt traditional cultural symbols and language and represented themselves as ＂land dwellers＂ in order to strengthen their status and power. The embankment project was intended not only to reclaim farm land from the lake waters but also to assert rights over the lake's fishery. The struggle for control of the lake was disguised as a struggle for land reclamation, and the significance of the fishery was obscured under the label of agricultural development.