How does a dam change the dynamics of a river system?

Changes flow regime downstream (decreases variability):

Changes water chemistry and temperature downstream:

Loss of water from reservoir basin due to ground seepage:

Loss of water due to evaporation:

Changes sediment load downstream (decreases it), serving as a sediment trap.

Produces a shore line environment:

Produces a lake environment, potentially increasing the biodiversity.

Changes load on the crust, potentially producing reservoir-induced seismicity.

Dam safety issues:

Some dam links:

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