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In this lesson we are going to discuss about the drainage systems and the types

Answer Text:
Drainage Systems
- Main river together with its tributaries.
Types
1. Accordant Drainage System
- Drainage system in which a river flows according to slope and rock structure by following areas of weak lines.
2. Discordant Drainage System
- Drainage systems in which rivers don’t flow in accordance with the slope, rock structure and land forming processes.
Types
a) Antecedent Drainage System
- Drainage system where a river maintains its course while the surrounding land is being uplifted.
b) Superimposed Drainage System
- Drainage system which develops where a river maintains its flow over a new set of rocks after removing a former set of rocks.
3. Back Tilted/Reversed Drainage System
- Drainage system where direction of flow is reversed be due to capture, uplifting or down warping e.g. R. Kagera, Katonga and Kafu.

Significance of Rivers and Their Features
Positive
a) Rivers are sources of water for domestic and industrial use.
b) Rivers water is used for irrigation.
c) They provide port facilities where they have rias and estuaries.
d) Some rivers are used for transportation e.g. R. Congo and Nile.
e) Some rivers are fishing grounds e.g. Tana.
f) Rivers are dammed and used for H.E.P generation.
g) Features formed by river action such as waterfalls, gorges and oxbow lakes are a tourist attraction.

Negative
a) Rivers flood causing loss of life and property.
b) Rivers may lead to drowning accidents especially when they are flooded.
c) River water can be a medium of spreading diseases such as bilharzia and malaria.
d) Some wide rivers are barriers to transport and communication.
e) Some rivers also harbour dangerous wild animals which can kill humans e.g. crocodiles, hippos and snakes.