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Dhanganga, Vangaga, Vardha, Indrawati, Manjra, Sabri etc.

Luni river starts from Pushkar, Rajasthan. Its length is 465 km and it ends in the Kutch of desert.

Girna, Mindola, Poorna, Panjag, Shipra, Arunavati etc.

Herawati, Hiranegi, Amravati, Kabani.

The Ganga is the most sacred river of India. The story of the Ganga from her source to sea from old times to new is the story of India’s civilisation and culture. The Ganga has its source near Gomukh glacier, near Gangotri. The Ganges is formed by two head streams namely Alaknanda and Bhagirathi. It enters the plains near Hardwar. The Yamuna meets this river at Allahabad known as Sangam. The Ganges is the master stream of the area—South of Farakka, the river divides into a number of channels to form ‘Sunder Ban’ Delta. The Ramganga, Ghaghra, Gandak, Baghmari join the Ganges from its left. The Yamuna and the Son join it from the south. It is 2525 km long. Hardwar, Kanpur, Allahabad, Varanasi, Patna and Kolkata are situated along the Ganga.

The Brahmaputra is the longest river in India, with a length of about 2880 kms. It rises near Mansarover lake in Tibet and enters India through Dihang gorge in Arunachal Pradesh. It flows parallel to the Himalayas in Tibet where it is known as ‘Tsangpo’. After Namcha Barwa (7767 m), it takes ‘U’ turn and enters India in Arunachal Pradesh through Dihang gorge. Dihang gorge is about 13000 metres deep. After the confluence of Lohit, Dihang and Dibang streams, it is called the Brahmaputra. It carries huge amount of silt with it. In northern Bangladesh, it is called Padma. Further south, the Ganga and the Brahmaputra meet and the joint stream is known as Jamuna and in central part, it is called Meghna. It is often compared to a slowly moving lake due to sluggish flow. It is known for its notorious floods in upper Assam. It forms the largest delta of the world, known as ‘Sunderbans’. It is the home of ‘Royal Bengal Tiger’.

These rivers have large basins. These make deep gorges. These were formed due to down cutting during period of uplift of Himalayas. These are perennial rivers as these get water from rainfall and from the melting of snow. These deposit silt and sand to form plains.

The rivers flowing to the west of Peninsular plateau are: Mahi, Sabarmati, Narmada and Tapti.

1. Mahi. Mahi river emerges from Vindhya mountains. It total length is 533 kilometres. It falls into the right side of Gulf of Khambhat, near gulf of Cambay.
2. Sabarmati. Sabarmati emerges from Mechhva near Udaipur. This seasonal river is 416 km. long. After passing through Gandhi Nagar and Ahmedabad, it falls into Gulf of Cambay.
3. Narmada. It emerges from Amarkantak Plateau, and after travelling 1312 km, falls into the south of Gulf of Cambay without forming any delta.

Most of the freshwater lakes of India are located in the Himalayan region. The lofty ranges of the Himalayas are snow covered and have many glaciers. Glacial activity results in the formation of circular hollows lip in the mountains. They are known as Cirques. The melting of the glacial snow in later period forms cirque lakes. As the lakes have water from snowmelt they are freshwater lakes, e.g., Pangong lake in Ladakh. 

Tectonic activity in the Himalayan region also results in the formation of depressions. They are filled with melting snow forming lakes of tectonic origin, e.g., the Wular Lake in Jammu and Kashmir, which is the largest freshwater lake in India. 

The Dal Lake of Srinagar, Bhimtal and Nainital of Uttarakhand, Loktak Lake of Manipur and Barapani Lake of Meghalaya are some other important freshwater lakes. All are located in the Himalayan region and the Purvanchals.

The area drained by a single river system, comprising a main river and its tributaries, is called its drainage basin or river basin. The term drainage describes the river system of an area. Small streams flowing from different directions come together to form the main river. It has number of tributaries and distributaries. The river ultimately drains into a large water body such as a lake or a sea or an ocean. 

The area drained by the main river, its tributaries and distributaries is termed as the river basin. The river Ganga has the largest river basin in India. The river Indus has a larger river basin but most of it lies outside India.

The river Krishna rises from a spring near Mahabaleshwar. It flows eastwards to the Bay of Bengal. It has a length of about 1400 km, which makes it the second longest river of Peninsular India after Godavari which has a length of 1500 km. 

The Tungabhadra, the Koyna, the Bhima, the Ghatprabha and the Musi are important tributaries of the river Krishna. The drainage basin of the river Krishna lies in Maharashtra, Karnataka and Andhra Pradesh.

A gorge is a very steep-sided, narrow river valley. It is found in the mountains in the upper courses of the rivers. They are near I-shaped in appearance. In the upper course the river is very swift as it descends down the steep slopes of the mountains. Vertical corrosion or downcutting is the predominant action of the river here. In areas where the rocks are very hard or resistant, the valley that develops in narrow and the sides are steep rising almost vertically. Such narrow river valleys are called gorges. Thus, gorges are found in mountainous terrain with resistant rocks. They are usually found in the upper reaches of the river in high mountains, e.g. the Indus Gorge, the Brahmaputra Gorge. 

Gorges are the features of youthful topography. In the Himalayas where the land has been uplifted in recent geological period, gorges are common.

Lagoon is a stretch of brackish or salt water separated from the sea by a sandbank, bars, reefs, etc. The action of wind and waves along coasts builds spits and bars in the inlets of seas isolating lagoons from the sea. They are commonly found off the deltas of large rivers like the Ganges, the Mahanadi, etc. 

The Chilika lake of Orissa, the Pulicat lake of Tamil Nadu and the Kolleru lake of Andhra Pradesh are lagoons. Strong on shore winds are also capable of pushing the coastal sand dunes along beaches landwards. They may enclose marshy lagoons. 

(i) Lagoons are found only in coastal areas, usually near the mouths of rivers, while lakes may be formed in any geographical location, in highlands or in inland basis. 

(ii) Lagoons have brackish water while a lake may have fresh water or salty water. 

(iii) Lagoons are formed due to wind and wave action in the coasts. Lakes may be of tectonic origin or may be formed due to river action, glacial action, and wind. They may also be human-made artificial lakes.

Lakes which have water with high salt content are called salt lakes. They are usually found in the basins of inland drainage in the regions of arid and semi-arid climate. Such lakes are seasonal in nature. 

Hollows may be created in the deserts due to the deflation action of the winds. These may reach the groundwater level which seeps out into these depressions. Small shallow lakes are formed which become salt lakes due to excessive evaporation. Sometimes short, intermittent streams drain into low depression or a desert basin and form temporary lakes. Such short lived lakes also contain high percentage of salts on account of high rate of evaporation. 

An example of such saltwater lake is the Sambhar lake of Rajasthan. The water of this salt lake is used for producing salt.