Which mechanical effect limited the canal dimensions used during the early Mesopotamian Uruk period?

💡 Explanation

When canals exceeded a critical depth and lacked proper reinforcement (pre-concrete era), slope instability and increased hydraulic forces caused bank erosion because cohesive strength of the soil couldn't withstand the stress. Therefore, bank erosion resulting in collapses was the primary limitation, rather than sedimentation, brackish intrusion, or salinity, which are slow chemical effects.

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