P26
The Roman sewers and the medieval tower
In this archaeological area, a part of the sewer of Alba Pompeia can be seen. This structure had been
reused in middle Ages as base of a tower. This sector of the sewer was related to one of the minor
cardines.
The construction of the drainage system resulted a basic part of the foundation project of the city,
following a unitary urbanistic project. The main sewer channels positioned under the cardines and
carried the water from south to north; the decumani from east to west. Their floor consists in
sandstones tiles, the lateral walls in pebble stones mixed with cement, the vault in tightly fitted
sandstones. All galleries are 150 cm wide, whereas the heights change from 160 cm to 60 cm. The
connection of the system itself was obtained by slopes between the main channels and the
secondary ones. They corresponded with the crossroads in centre of which there were sewer covers.
In the Roman cities, the sewer had to keep clean the streets and, secondarily, the richest houses,
thermal baths or latrinae.
1) The survey of the North-South sewer
2) Reconstruction of the sewers crossroad