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  • Lock on Canale San Leopoldo for draining the Lake of Castiglione, Castiglione della Pescaia (GR).zoom in altra finestra
  • Lock on Canale San Leopoldo for draining the Lake of Castiglione, Castiglione della Pescaia (GR).zoom in altra finestra

Bonifica del Lago di Castiglione - Chiusa sul Canale San Leopoldo [Reclamation of Castiglione Lake - Sluice on the San Leopoldo Canal]

The flat coastal area of today’s province of Grosseto was the swampland of Tuscany that for centuries posed the greatest difficulties from the viewpoint of environmental reclamation. The exploitation policies of the Medici age aimed at boosting agriculture and pasturage in the area, though the presence of the large Castiglione Lake, which in the 16th century had an extension of approximately 50 km 2 , strongly limited development. At the same time, however, fish farming guaranteed the government one of the most substantial incomes of its entire landed patrimony.

Grand Duke Ferdinando I de’ Medici attended to the realisation of many hydraulic works, in 1592 instituting the Canals Office of Grosseto, which was the most important measure adopted to remedy the area’s hydraulic precariousness. Indeed, for the first time, the ruler appointed a local decentralised authority to coordinate, control and define reclamation initiatives in a province that was scarcely populated and perpetually devastated by the incursions of wild livestock that caused the systematic destruction of any and all hydraulic constructions.

During the Lorraine Regency, a team of engineers launched the integral reclamation plan of Maremma, which was subsequently supported by Grand Duke Peter Leopold. With its realisation entrusted to Leonardo Ximenes who described its features in his famous work, Della Fisica riduzione della Maremma senese, this project abandoned the previously attempted idea of filling Castiglione Lake, and instead aimed at exploiting it for production by means of a systematic and rational regulation of its waters. "Refreshment" canals were dug in order to allow the regulated introduction of waters from the Ombrone River into the lake, so as to avoid stagnation. Furthermore, in order to control and facilitate the outflow of lake waters towards the sea, the Floodgates Building was constructed on a project by Ximenes, and the Canale Reale or Maestro was excavated nearby. Pietro Ferroni, who succeeded Ximenes in 1781, retrieved the old project to drain Castiglione Lake and carried out its partial filling. The Lake’s definitive filling was carried through in the course of the first half of the 19th century, thanks to the study by Vittorio Fossombroni, which implemented the most impressive reclamation measure of Maremma in the provinces of Pisa and Grosseto. Launched with a decree by Grand Duke Leopold II on November 27, 1828 and set forth by Fossombroni in his famous, Memoria sulla Grossetana [Memorial on the Grosseto Territory], the project was carried out under the technical direction of Alessandro Manetti. The lake water was collected in five reclamation basins, and then emptied into the sea by means of three specially excavated effluents equipped with sluice-gates: the Bilogio, San Leopoldo (still visible today) and San Rocco. The beds of various canals were dug, little subterranean tanks were built and the tract of the Via Emilia-Aurelia between Cecina and Grosseto was modified: using the most sophisticated technologies and with a considerable outlay of human and economic resources, it was thereby possible to give a decisive turn to disposing of this difficult territory.


Texts by Graziano Magrini

English translation by Victor Beard

Last update 12/mar/2008