This article focuses on a document printed in 1820 entitled Rapport au roi sur la navigation intérieure (King’s report on internal navigation) in order to analyse the history of public action and planning under the Restoration Monarchy. The research has three key focuses and analyses successively the context in which the report appeared, its form and content and how it was produced from a material and intellectual perspective, and the immediate circumstances in which it was circulated. This document emerges as the manifesto of a new figure of the State as planner that came to the fore in the administrative-political context of early 1820s France. It was underpinned by a wide range of expertise and set out a structured programme for waterway development. The report reflects the changes at work within the public works department (administration des ponts et chaussées) as the reconfiguration of relations between the executive and the legislature. It also embodies reforms carried out and politics pursued and constitutes the key implementation instrument of these. The resulting public works administration would subsequently be challenged by the July Revolution.