In the 16th century, rapid population expansion paired with Elche’s arid environment prompted canal expansion. In 1529, Elche officials constructed the "Contraséquia" section to prevent Vinalopó river flooding and irrigate crop fields with the excess flow. The canal extension distributed water to a reservoir north of the town then south to the "Séquia Major" for crop irrigation. From 1632 to 1646, Elche residents built a dam to reinforce the "Contraséquia". The dam stored and channeled any excess drainage from the nearby Tarafa stream into the canal network. Frequent reservoir clogging and elevated salinity levels from evaporation limited the dam’s impact. As the canal network expanded, so too did the need for water administration. The "Libro Major" and "Libro Chico" water books recorded rights and dates for water distribution in "tanda" (irrigation round) or 37.5 day sessions. Every landowner received water at a specified time and water part. The irrigation system distributed water in a two-ring system composed of "huerto" water and "dula" water. The first ring contained "huerto" water for urban consumption and palm groves within Elche. The second ring comprised "dula" water for crop irrigation outside Elche city limits. Greater irrigation distance resulted in stricter standards for dula water. The "tandas" and ring system lost function in the 20th century. As Elche industrialized in the late 19th and 20th century, the canal system and palm grove production declined.