Occurrence of Attributes in Original Text

The text related to the cultural heritage 'Historic Fortified Town of Campeche' has mentioned 'Lagoon' in the following places:

Occurrence Sentence	Text Source
To remedy this problem, the Maya developed an advanced system of hydraulic works: a network of canals drained the valley and the water was taken to a lagoon, which was transformed into dam through retaining walls, while other canals were used to irrigate the fields.	WIKI