Inadequate surface drainage and encroachment in the floodplains has caused the floods of Kashmir.
ByDr. Nitish PriyadarshiGeologistRanchi
Heavy rainfalls battered the western Himalayas last week due to a clash between monsoon currents and winds from the Caspian Sea. The Srinagar weather station – in the summer capital of the Indian state of Jammu and Kashmir – recorded 250 mm of rain between September 3-6.
For hundreds of million years Kashmir Valley is supposed to have remained under Tethys Sea and the high sedimentary-rock hills seen in the valley now were once under water. Geologists have come to believe that Kashmir Valley was earlier affected by earthquakes. Once there was such a devastating earthquake that it broke open the mountain wall at Baramulla and the water of the Satisar lake flowed out leaving behind latchstring mud on the margins of the mountains known as karewas. Thus came into existence the oval but irregular Valley of Kashmir.
In September 2014, the Kashmir region was hit by heavy floods from torrential monsoon rains. The regions of Jammu and Kashmir in India, as well as Azad Kashmir, Gilgit-Baltistan and Punjab in Pakistan, were affected by these floods.
The cause of the flood is continuous heavy rainfall due to which local rivers broke out into the streets. The areas affected by the flood are mostly districts in south kashmir which include Anantnag, Avantipore and Pulwama.
The main rivers in this region are Ravi, Chenab and Jhelum. These rivers are the tributaries of the Indus. They carry quite substantial discharges during monsoon and also large volume of sediment. They change their course frequently and leave behind vast tract of sandy waste. The major problem is that of inadequate surface drainage which causes inundation and water-logging over vast areas.
The river Jhelum rises from Verinag Spring situated at the foot of the Pir Panjal in the south-eastern part of the valley of Kashmir in India. It flows through Srinagar and the Wular lake before entering Pakistan through a deep narrow gorge.
Floods in Jammu and Kashmir aren’t exactly an uncommon phenomenon, if history and indeed its geography is to be believed. Starting last week, the state has seen an unprecedented amount of rainfall, resulting in its worst floods since 1959. Floods in the state are invariably linked to the Jhelum River and its history of crossing the danger mark, its streams and rivulets overflowing and thereby inundating the “Valley” (south Kashmir) in the process.
In the last 60 years, more than 40 percent of lakes, ponds and wetlands of Srinagar have been encroached upon for constructing buildings and roads. The banks of the Jhelum river have been taken over in a similar manner, vastly reducing the river's drainage capacity.
Jhelum which is a main source of irrigation in the Valley has been marred by extensive siltation in last few decades. In absence of any conservation measures, the river had lost its carrying capacity and led to blockage of its lone outflow channel in Baramulla, posing a risk of floods in the Valley.
The resultant floods – which have killed almost 400 people in India and Pakistan and displaced tens of thousands more – were perhaps inevitable. But they would not have become so devastating if the riverbeds and lakebeds had not been raised by silt, while their banks were encroached upon by ill-planned buildings.
There are three reasons why the floods have caused so much damage:
- deforestation in the catchment areas of rivers – especially Jhelum, Chenab and Indus – and of streams;
- unplanned construction of buildings and roads, especially in the floodplains of the rivers and the banks of the lakes;
- rampant and unchecked dumping of garbage in the rivers and lakes;
Without the roots to hold the soil on the steep mountain slopes, it has all been washing down to the streams in the form of silt, and raising the riverbeds. The obvious consequence – the water carrying capacity of the streams and rivers is much reduced.
Coming to the second reason, for decades the elite in the Kashmir valley has been building fancy villas right on the floodplains of rivers and streams, sometimes even on tiny islands in the middle of the river. The process has been repeated and accelerated on the banks of famous lakes like Dal and Nageen in Srinagar, with some hotels and restaurants even being built with their foundations in the lake – a result of the tourism boom.
As the Jhelum River meanders through Srinagar, every neighbourhood adds its untreated household garbage to the river – once again a recipe for choked riverbeds and lakebeds and for the water to overflow whenever it rains heavily.
Overuse of chemical fertilisers, especially in the fruit orchards throughout Kashmir, also exacerbates flooding. The excess fertiliser gets washed into streams and rivers, where it causes eutrophication, and again leads to algae blooms which choke waterways.
Jhelum meanders in a serpentine way from South to North Kashmir and settles in Wullar, Asia’s largest freshwater lake, before pouring into Pakistan administered Kashmir through Baramulla. Experts said the devastating flood in 1959 caused backwater effects to Jhelum due to low outflows from Wullar Lake in north Kashmir which has been nearly chocked by heavy accumulation of silt and narrow outflow channel.
There are number of rivers, tributaries and nullahs which are joining Jehlum River. For proper water resources management, sufficient amounts of hydrological data are required. But sufficient hydrological data on these rivers, tributaries and nullahs are not available. Some of the reasons behind the lack of the data are:
1) The area is mountainous with some of the world’s highest mountains situated in it. 2) The accessibility of many places is very difficult, especially in the winter season.
Observers are bemoaning that Srinagar is looking like a vast lake. Urban planners, environmentalists or anybody with common sense is not surprised. Without immediate corrective action, the calamity is likely to strike again.
Reference:
http://www.livemint.com/Politics/5Pq6ov9rVifupnpxQJUo1O/Jammu-and-Kashmir-has-had-a-long-history-of-flooding.htmlhttp://www.dredge.com/jhelum-river-dredging.htmlhttp://www.academicjournals.org/article/article1379512604_Zakaullah%20et%20al.pdfhttp://www.thethirdpole.net/choked-riverbeds-worsen-floods-in-kashmir/