In Thailand, where water and land intertwine to shape the livelihood and identity of people, engineering bureaucracy and mechanical technology have both played significant roles in producing national ideology. At the same time, bureaucracy and technologies are historical products. In this contribution, I explore Thailand’s Royal Irrigation Department (RID) Museum for Heavy Engineering and argues that the museum—instantiating a parliament of things (Latour) engineered into exhibition—participated in the shaping of the Thai water engineering community and the shaping of Thai statecraft. Operating through selective portrayals and juxtapositions of engineers, technologies, bureaucracies, and natural events, the parliament of things composed by the exhibits encompasses not only the intimate entanglements between the bodies of engineers and machines, and between machines and bureaucracy, but also mythical and cosmological elements like divine stones and naga vehicles. In this way, the museum parliament testifies to a blurring of nature, society and divinity occurring at the very heart of the Thai engineered state. It articulates Thai water engineering as a nonmodern assemblage beholden neither to the dichotomy of nature and culture, nor to any clear distinctions between science, politics and cosmology. Paradoxically, this nonmodern assemblage has been central in propelling forward the seemingly high-modern practice of Thai water engineering.