嘉南大圳在1930年宣告竣工，這個號稱半官民實則由總督府政策主導的水利事業，創下當時的許多紀錄。本文首先分析嘉南大圳宣導影片〈幸福的農民〉之攝製、宣傳與內容，探討官方的宣傳及其殖民主義意識型態傳播。其次藉由一個殖民地方末端行政吏員－保正作家蔡秋桐的〈放屎百姓〉、〈新興的悲哀〉、〈興兄〉等小說以及農民組合對嘉南大圳事業的批判，探討文本中的反宣導意義，指出其如何解構宣傳教化影片中的偽紀實，也挑戰了官方論述所宣揚的權威。最後，總結全文，揭示在此一官／民殖民主義論述與反論述之文本縫隙中，所展現的歷史與社會意義。

The construction of Jialan dazun (Jialan Great Ditches) was completed in 1930. This public-private cooperative irrigation project under the guide of the colonial government was record-breaking in many respects. This article first analyzes the production, promotion, and content of a propaganda film entitled "Happy Farmers", and demonstrates how the official colonial ideologies were propagated. Secondly, the article discusses the writer Tsai Chiutong's short stories as well as investigates the Farmers' Association's critique of this grand irrigation project, in order to locate an anti-colonial message in Tsai's stories. This article argues that these stories deconstructed the pseudo-realism of the official documentary film and challenged the legitimacy of the colonial worldview. In conclusion, this article reveals historical and social meanings masked in a textual discrepancy between official colonial discourses and anti-colonial ones.