Wular Lake

Topic: Drainage System of India: Rivers, Basins and Patterns · NCERT: Class 11, Ch 3 "Drainage System"

Meaning

Wular Lake is a large freshwater lake in the Kashmir valley, near Bandipora and north of Srinagar. The Jhelum river flows into it and out of it. It is one of Asia's largest freshwater lakes, and its Ramsar description calls it India's largest freshwater lake [3].

It matters because it acts as a natural flood basin for the Jhelum. It has been a Ramsar site since 23 March 1990 [2][3]. It is also shrinking, which makes it a standard example of a lake in decline.

Explanation

How it formed

• Wular is partly a tectonic lake. A tectonic lake forms when earth movements, such as faulting or folding, create a hollow in the land that then fills with water.
• At Wular, part of the valley floor sank, leaving a low area.

• Water collected in this low area.

• The Jhelum also shapes the lake. The river brings in water and silt, and it changes the size and shape of the lake over time.

How it works as a flood basin

• Flood basin means a low area that stores floodwater.
• The Jhelum passes through the lake.
• The river enters Wular.

• It leaves Wular near Sopore.

• What happens in a flood:

• Floodwater spreads into the wide lake instead of rushing straight downstream.
• The lake holds this water and lets it out slowly.

• As a result, the flood peak downstream is lower.

• This is one of the main jobs lakes do in a drainage system. They store extra water in the rains, release it slowly, and recharge groundwater (water stored underground in rock layers called aquifers).

Uses and value

• Water chestnut grows in its marshes. This brings in revenue and gives fodder for animals [3].
• It supports a large fishing industry [3].
• It supplies water for irrigation and for homes [3].
• Ramsar status: it was designated on 23 March 1990 and covers 18,900 ha [2][3].
• A Ramsar site is a wetland listed under the Ramsar Convention on Wetlands (1971, Ramsar, Iran) as a "Wetland of International Importance".

Why it is shrinking

• Siltation, which means silt filling up a lake bed:
• The catchment (the land that drains into the lake) has lost its forest cover.
• Rain washes soil off this bare land and into the lake.

• The lake becomes shallower and smaller.

• Encroachment, which means taking over the lake bed for other uses:

• Willow plantations have spread onto the lake bed.

• Farms have spread onto it too.

• Result: the lake has less open water, so it can store less floodwater. Flood risk in the valley goes up.

Where it occurs

• Union Territory: Jammu and Kashmir.
• Location: in the Kashmir valley, near Bandipora, north of Srinagar.
• River: the Jhelum flows into the lake and leaves it near Sopore.
• Tulbul navigation project:
• It is a barrage (a low dam with gates that controls the water level) planned at Wular's outlet.
• Its purpose is to keep the Jhelum navigable in the lean season (the dry months when river flow is low).

• Pakistan has objected to it under the Indus Waters Treaty (1960), so its status keeps changing.

• Other Indian lakes listed as Ramsar sites on the same day (23 March 1990): Loktak (Manipur) and Sambhar (Rajasthan) [2].

Don't confuse with

• Loktak Lake (Manipur): Loktak is the largest freshwater lake in North-East India, and it has floating phumdis (mats of weeds, soil and rotting plants). Wular is in Kashmir and has no phumdis. Both became Ramsar sites on 23 March 1990 [2].
• Pangong Tso (Ladakh): both are tectonic lakes. But Pangong Tso is endorheic (it has no outlet, and water leaves only by evaporation), so its water is brackish (slightly salty). Wular is freshwater, and a river (the Jhelum) flows out of it.
• Chilika Lake (Odisha): Chilika is Asia's largest brackish-water lagoon, a coastal lake mixing river water and sea water. Wular is an inland freshwater lake.
• Sambhar Lake (Rajasthan): Sambhar is India's largest inland saline lake, a closed basin where water evaporates and leaves salt behind. Wular is freshwater because the Jhelum carries water through it.

Prelims Hooks

• Wular – Jhelum – Kashmir valley (near Bandipora): the Jhelum enters the lake and leaves near Sopore.
• Ramsar designation: 23 March 1990, 18,900 ha [2][3]. Wular, Loktak and Sambhar were all designated on the same day [2].
• Size trap: Wular is one of Asia's largest freshwater lakes, and its Ramsar description calls it India's largest freshwater lake [3]. Do not confuse it with Chilika, which is the largest brackish lagoon.
• Origin: partly tectonic (a sag in the valley floor), and also shaped by the Jhelum.
• Tulbul navigation project: a barrage planned at Wular's outlet. Pakistan has objected to it under the Indus Waters Treaty (1960).
• Products: water chestnut from its marshes and a large fishing industry [3].

Mains Points

• Lakes are part of flood control.
• Wular soaks up Jhelum floodwater and releases it slowly.

• When the lake shrinks, it stores less water, so flood peaks in the Kashmir valley rise (GS-I geography; GS-III disasters).

• How Wular is declining:

• Deforestation in the catchment causes siltation, which makes the lake shallower.
• Willow plantations and farms encroach on the lake bed.
• Result: less open water, smaller fisheries and lost biodiversity [4][3].

• Possible responses: restore the catchment, clear encroachments, and set up a dedicated lake authority, as was done for Chilika and Loktak.

• Water, development and geopolitics overlap.

• The Tulbul project would help navigation on the Jhelum in the lean season.
• Pakistan's objection under the Indus Waters Treaty (1960) shows how one lake on a shared river can become an international dispute (GS-II/GS-III).

Related concepts

• Loktak Lake
• Pangong Tso
• Chilika Lake
• Pulicat Lake
• Kolleru Lake
• Vembanad Lake
• Sambhar Lake

Read more

• Lakes of India