Drainage System Class 9 GSEB Solutions Social Science Chapter 15

Gujarat Board Class 9 Social Science Drainage System Textbook Questions and Answers

1. Write short answer for the following questions.
Question 1. Give difference: Himalayan rivers and Peninsular rivers.
Answer:
Himalayan Rivers

1. These rivers contain water throughout the year.
2. They are long, deep and having slow flow.
3. They are used as waterways.
4. Their river basin areas are large.
5. Meanders are seen.

Peninsular Rivers

1. These rivers are seasonal.
2. They are short, shallow and having fast flow.
3. They cannot be used as waterways.
4. Their river basin areas are comparatively.
5. Meanders are not seen.

Question 2. Explain Drainage Pattern and Water Divide.
Answer:

1. The word drainage system is used for the systematic pattern of rivers.
2. It is seen that one main river along with its tributaries come from different directions and meet into a single river.
3. The water of these rivers is emptied into a water reservoir, sea or a desert. Thus, when a flow of a river flows through its system in any area it is called a river basin.
4. When a mountain or an upland separates the flow of water from one another, it is called water divide.

Question 3. Explain the utility of lakes.
Answer:
Utility of Lakes

1. They are used for navigation and hydropower generation.
2. They help to regulate the flow of a river.
3. They also moderate the climate of surroundings.
4. They maintain the aquatic system.
5. They help develop tourism.
6. They enhance natural beauty and provide recreation.

Question 4. State the remedies to prevent water pollution.
Answer:

1. Water purification projects must be implemented through National River Conservation Project.
2. Industrial units should filter harmful contents from the chemical effluents released by them in rivers.
3. Every citizen should take care not to mix up the domestic waste into rivers.
4. Strict rules should be formed to prevent industrial units from releasing industrial effluents in rivers.

Question 5. ‘Godavari is named as Ganga of South’. Give reasons.
Answer:

1. It has the largest basin among the peninsular rivers.
2. It starts from the slopes of Western Ghats near Nasik in Maharashtra.
3. It flows to the east and meets Bay of Bengal.
4. About 50% of its basin lies in Maharashtra and the rest is in Madhya Pradesh and Andhra Pradesh.
5. The length of Godavari is about 1465 km. Many tributaries meet Godavari. Among them Puma, Vardha, Pranhita, Manjara, Vainganga and Penganga are included.
6. Godavari has a longer flow and large basin. So, it is called as ‘Ganga of South’.

2. Answer the following. 
Question 1. Explain the Ganga River System.
Answer:

1. River Bhagirathi and Alaknanda emerging from the Gangotri area in Himalayas, merge with each other near Devprayag (Uttarakhand). Hence, Ganga river leave the mountains terrain and enters plains near Haridwar.
2. Many Himalayan rivers like Ghaghra, Gandak and Kosi meet Ganga.
3. Yamuna emerges from Yamnotri in Himalayas flowing to the right side of Ganga, it merges with Ganga near Allahabad.
4. The origin of Ghaghra, Gandak and Kosi rivers lies in Nepal. Hence, the northern plain experiences flood disasters every year.
5. India has been able to attain prosperity in agriculture through fertile plains formed by these rivers.
6. Chambal and Betwa originate in peninsular plateau and meet Yamuna. Son river meets Ganga.
7. The combined flow of rivers from north and south is divided ahead into two branches.
8. One branch enters Bangladesh and is known there as Padma while another branch is known as Bhagirathi-Hugli in West Bengal. Finally these two branches meet the Bay of Bengal.
9. The flow of Ganga which is known as Padma in Bangladesh merges there with Brahmaputra river and their combined flow is known as ‘Meghna’.
10. The Ganga-Brahmaputra delta is the most fertile delta. It is known as ‘Sunderban’.

Question 2. Discuss the Narmada Basin.
Answer:

1. Narmada originates near Amarkantak plateau in Madhya Pradesh flow Westwards in rift valley.
2. Narmada Basin is spread in Madhya Pradesh and Gujarat.
3. The length of Narmada is 1312 km.
4. The length of its tributaries is not very long. So, most of the river meet at right angles.
5. River Narmada flows through a rocky terrain of marbles. It flow’s faster due to slope. The Dhuadhar falls are located here.

Question 3. Describe in detail Krishna and Kaveri basin.
Answer:
Krishna Basin:

1. It starts from Mahabaleshwar in Maharashtra.
2. Its tributaries are Tungabhadra, Koyna, Ghatprabha, Musi and Bhima.
3. Its basin extends in Maharashtra, Karnataka and Andhra Pradesh.
4. Its tributaries length is about 1400 km.

Kaveri Basin:

1. It has its origin in the Brahmagiri Range in Western Ghats.
2. Amravati, Bhavani, Hemvati and Kalini are its main tributaries.
3. It is spread over a Kerala, Karnataka and Tamil Nadu.
4. River Kaveri meets the Bay of Bengal to the South of Cuddalore in Tamil Nadu.

4. Find out the correct option from the given options: 
Question 1. Which lakes are formed due to meandering of rivers?
A. Lagoon
B. Ox-bow
C. Oval-shape
D. Square
Answer:
B. Ox-bow

Question 2. What is it called when a mountain or an upland separates the water flow of rivers from one another?
A. Water formation
B. Water divide
C. River system
D. Basin
Answer:
B. Water divide

Question 3. Which of the following is not a peninsular river?
A. Godavari
B. Krishna
C. Kosi
D. Kaveri
Answer:
C. Kosi

Question 4. Which of the following lakes is used for producing salt?
A. Dhebar
B. Sambhar
C. Wuler
D. Nal
Answer:
B. Sambhar

Question 5. Which are the main tributaries of Ganga?
A. Yamuna, Ghaghra, Gandak and Kosi
B. Yamuna, Chambal, Ghaghra and Kosi
C. Yamuna, Ghaghra, Sharavati and Kosi
D. Narmada, Ghaghra, Gandak and Kosi
Answer:
A. Yamuna, Ghaghra, Gandak and Kosi