A dam is a barrier that stops or restricts the flow of water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation, human consumption, industrial use, aquaculture, and navigability

Introduction:
The means of irrigation that were built around 2500 years ago include canals, wells, and artificial lakes. These irrigation systems were developed by ancient civilizations to ensure a consistent water supply for agriculture.

Explanation:
- Canals: Canals were one of the primary means of irrigation built around 2500 years ago. These artificial waterways were designed to divert water from rivers to agricultural fields. Canals helped in efficiently distributing water to different areas, ensuring that crops received an adequate water supply. They were constructed using manual labor and were often connected to larger river systems.

- Wells: Wells were another important means of irrigation during this time period. Wells were dug deep into the ground to reach underground water sources, such as aquifers. They provided a localized water supply for nearby fields. Wells were constructed using rudimentary tools and techniques, and their depth varied depending on the availability of water sources.

- Artificial Lakes: Artificial lakes, also known as reservoirs, were created by damming rivers or streams. These large bodies of water acted as storage facilities for irrigation purposes. The water stored in these lakes could be used during dry seasons or periods of low rainfall. Artificial lakes were constructed by building dams using stones, mud, or other available materials.

Conclusion:
In conclusion, canals, wells, and artificial lakes were all means of irrigation that were built around 2500 years ago. These irrigation systems played a crucial role in sustaining agricultural activities and ensuring a reliable water supply for crops. The development of these irrigation methods showcased the ingenuity and engineering skills of ancient civilizations in managing water resources for agriculture.

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