Works on Alicorno canal

The Alicorno is one of the man-made canals that flow through the historic city centre of Padua. It was built to create a secondary branch of the River Bacchiglione, which is how the name Alicorno came about: derived from the Latin alius cornii, it means “other branch”.

The canal is thought to have been dug around 1230 by the Benedictine monks to water the gardens situated within the city walls and to power the mills operating in the area.

Today, the route taken by the canal — mostly culverted — passes across Prato della Valle, where it refreshes the stream around the Isola Memmia, and then on, above ground, to the Botanical Garden; thereafter, it merges with the Santa Chiara canal downstream of Pontecorvo and becomes a landscape feature of the historic Parco Treves, before terminating as the Alicorno and continuing as the San Massimo canal.

The most recent hydraulic works of any importance were undertaken in 1946, and involved regulation of the Alicorno canal bed (together with cleaning of the Prato della Valle canal), whereas today the canal presents lengthy sections that were converted into conduit in 1954, in accordance with a project entrusted by the municipality to Francesco Marzolo, professor of hydraulic engineering at the University of Padua.

Seventy years on, September 2024 saw the start of works to repair and upgrade the stretch of the Alicorno canal that runs past the Botanical Garden.

By virtue of an understanding between the University and the Bacchiglione river authority, the exposed stretch of 300 metres flowing alongside the Hortus cinctus will undergo operations to clean the bed, effecting the removal and disposal of silt and sludge, and improve the condition of the banks by sinking chestnut piles and using stone to face and consolidate the exposed surfaces. In addition, the vegetation along the canal will be cut back or pruned as appropriate, preserving species of wild plant life that grow naturally in wetlands.

The aim of the works, prompted by the desire to preserve a part of the city’s historic and environmental heritage that has been sorely tested by a high population density in the area, is to clean up the canal bed, by now heavily silted with ferrous residues and solid urban waste estimated as amounting to some 500 m³ of material lying about 20 cm deep.

Given the status of the canal — which for centuries has performed the essential task of guaranteeing the Botanical Garden a supply of water — and today, the adverse effects of periodic water crises (in 2023, an operation was carried out to save all the fish species present), this is both a rebirth and an opportunity for the entire local community to rediscover an important chapter in the history of Padua and its special relationship with water.

The project is part of an action programme for the recovery and valorization of the Botanical Garden, presented by the University of Padua through the Centro di Ateneo Orto botanico (Botanical Garden University Centre) and funded by the Ministry of Culture with a grant of €270,000.