Engr. Amir Adnan's document discusses spillways and fish ladders. A spillway is part of a dam designed to allow water to flow safely over the dam during floods to prevent overtopping. Spillways provide a safe release of flood waters from the dam downstream, usually to the river the dam was built on. Spillways draw water from the top of the reservoir to avoid situations where flood waters would cause the reservoir level to rise and potentially overtop the dam. Controlled spillways have gates that can be raised or lowered, providing advantages over uncontrolled spillways. Fish ladders are structures that allow fish to pass through dams to access spawning habitats.

1. Engr. Amir Adnan
B. Sc. in Civil Engineering

4. Spillway Fish Ladder

5. Water Resources Engineering (6475)
Chapter:- River Head Works
7th Semester, 1st Shift.
Civil Technology.
Time:- 50 Min

6. What is Spillway and Why It is Used?
Types of Spillway
What is Fish Ladder and Why it is Used?

7. A spillway is part of a dam that
is designed to allow water to flow freely
over the dam during floods. Spillways are
structures constructed to provide safe
release of flood waters from a dam to a
downstream , normally the river on which
the dam has been constructed.
What is spillway?

8. Every reservoir has a certain capacity to store
water. If the reservoir is full and flood waters enter
the same, the reservoir level will go up and may
eventually result in over-topping of the dam. To
avoid this situation, the flood has to be passed to
the downstream and this is done by providing a
spillway which draws water from the top of the
reservoir. A spillway can be a part of the dam or
separate from it.
Why Spillway is Used?

9. Spillways can be controlled or
uncontrolled. A controlled spillway is
provided with gates which can be raised
or lowered. Controlled spillways have
certain advantages as will be clear from
the discussion that follows. When a
reservoir is full, its water level will be the
same as the crest level of the spillway.