Rotaldo

Rotaldo
Location within southern Piedmont
Country	Italy
Basin features
Main source	near Grazzano Badoglio (Province of Asti) 264 m (866 ft)
River mouth	Po near Valmacca (Province of Alessandria)
Physical characteristics
Length	40 km (25 mi)
Discharge	Average rate: 1.6 m3/s (57 cu ft/s)

The Rotaldo, known in its upper course as the Laio, is a 40-kilometre (25 mi) river (classified as a torrente) of northern Italy, and a right-side tributary of the Po. Most of its course falls within the Province of Alessandria; all of it within the former Province of Casale. The river is of modest flow, heavily reliant on rainfall, with a discharge near its mouth of 1.6 cubic metres per second (57 cu ft/s).

The river is born as the Laio on the slopes of Madonna dei Monti near Grazzano Badoglio in the Province of Asti, close to one of the springs of the Grana del Monferrato. Its early course makes an arc through the hills of the Basso Monferrato, heading first west-southwest then curving gradually to west-northwest, receiving the waters of a number of small streams from the left and passing through the commune of Olivola and between Vignale Monferrato and Frassinello Monferrato. At Roncaglia it is joined from the left by a second branch whose main source is in the hills near Ottiglio and which has been joined by streams rising in Sala Monferrato, Cella Monte and Rosignano Monferrato. From the right it receives streams arising in Camagna Monferrato and Conzano. At San Maurizio (near Occimiano) it is joined from the left by a further branch with its origins near Terruggia. Entering the Casalese plain it acquires the name Rotaldo and follows a sinuous course, passing through Borgo San Martino, Ticineto, and Valmacca where it is joined from the left by the Gattola. It enters the Po at Bozzole.