Significance of Wetlands on Flood plains of River Jhelum
Wetlands are the great store houses of rich and varied biodiversity and fulfill a wide range of essential key functions which include flood control, shoreline stabilization against wave erosion, trapping sediments, natural sewage treatment, recharging of aquifers and abating pollution.
According to the Ministry of Environment and Forests Govt. of India, in their estimation of 1990 the J&K State has 291.07 sq.Km area under the wetlands while as Space Application Centre, Ahmadabad,ISRO identified and mapped 42 wetlands in the State occupying an area of 4067.79 Km.
The wetlands in Kashmir are directly or indirectly connected longitudinally as well as altitudinaly with river Jhelum. Most of the tributaries of Jhelum originate from glacial lakes and govern the base flow of the river. The functions and process of Valley lakes are linked with those of glaciated and pine forest lakes. Changes in land uses within the catchments effecting hydrological processes have a profound impact on the biodiversity and socio- economics. Therefore, management of river Jhelum or the wetlands falling in its basin cannot be addressed in isolation or in patches, without recognising interconnectivity of wetlands with their catchment at river basin level.
River basin level planning requires understanding of the carrying capacity of the river basin with a view to produce desired goods and services from limited resource base and achieve equitable quality of life while maintaining deswired environmental quality in the region. The challenge, therefore is to conserve Wetland Ecosystems along their rich biodiversity while providing sustained economic benefits to the communities dependant upon these resources for their sustenance.
The Jhelum basin is inhabited by 5.4 million people within its 34 towns and 2846 villages.The population concentration within the valley,accounts for 84% of the total population,with the rest sparsely distributed within the hills. The Jhelum basin as such extends to an area of 12777 sq.km comprising 24 watersheds. There are 14 watersheds of River Jhelum prior to entry into Wular extending 8627sqkm ,while as Wular sub catchment comprises of 6 watersheds directly draining into Wular extending 1144 sq km and Wular downstream comprises of 3 watersheds of river Jhelum below Wular extending to 3006 sq km.
On the basis of historical trends in water inflow and outflow of Wular lake (1900-1960 ) and the water holding capacity (1922-2003 ), following conclusions could be drawn:
1) River Jehlum is the largest contributor of water inflows (88%) into the Wular lake, the rest being from the immediate catchments and precipitation. Similarly, the outflows through river Jehlum is the highest (96.9%), the rest accounted for by human abstraction (1.7%) and evaporation (1.4%)
2) There is a high temporal variability in inflows and outflows. 80% of the inflows and 86% of outflows take place in Summer.
3) The net outflow from the Wular measured at Sopore are higher than the inflows. The wetland system is net absorber of water from September to February, which is the released during March to june. During a flood year the net outflow from the wetland systems are positive which is reverse incase of drought year leading to periodic floods and droughts. The storages are usually built during the winter months, when the flows are already in the lean phase.(WISA-2007).
The drastic changes in the hydrological regimes have been observed which are attributed to loss of marshes, degradation of catchments, wetlands and climate change. There has been a progressive reduction in the capacity of the wetlands to regulate flow regimes. This has led to enhanced flooding and quick drainability within the basin. The high flows largely remain untapped due to reduced retention capacity of the basin attributed to loss of upstream marshes and wetlands. This trend is likely to enhance situations of hydrological extremities viz; droughts in the lean seasons and floods in the high flow seasons.
The nature and role of Wetlands has not been clearly understood by the Developmental Planners although the importance of Wular in the hydrography of Kashmir is being often quoted. The marshes were considered as obstacles in the process of Development, and hence converted for settlements of expanding population of Srinagar City. Short term strategies were developed as is quite evident from the newly establishments, Housing colonies, other Governmental and non Governmental establishments all along By Pass road right from Athwajin to Bemina,Hokera surroundings, Mir gund ,Indra nagar wetland, Narkara wetland etc. without understanding their interconnectivity and critical role on overall water Management for the region. Having relocated various settlements and colonies on these wetlands, they appear apparently on reclaimed lands but fact is that they are on water bodies and these areas will always be subjected to inundation and are prone to devastation at the time of floods.
Flood protection schemes are designed leading to fragmentation of the Wetland regimes. In case of Wular the most prominent of the embankment is the third line of defence having height of 1580m msl which hydrologically isolates the marshes from the main lake.
The massive conversion of Wetlands which acted as a natural reservoirs for regulating flows has led to loss of water holding capacity of the entire basin. The changes in the regimes has thus led to enhanced frequency of floods as well as droughts.
Allan et al.2005 holds the geographical distribution of wetlands is likely to shift with changes in temperature and precipitation, with uncertain implications for net greenhouse gas emissions from wetlands. Changes in these ecosystem could have major negative effect on fresh water supplies, fisheries, biodiversity, tourism, inputs of nutrients and other pollutants into aquatic habitats will vary with rainfall and other characteristics of the watershed.
According to Islam and Rahmani (2008) the recent enactment of the Roshni Act by the J&K Govt. Has very serious consequences on the Wetlands, particularly Wular.The authors add that the Roshni Act has provisions of legalizing all the illegal encroachments. after payment of a token money by the encroachers.
Prof.Shakil Romshoo ( Sept;22.2014)while terming the Kashmir flood 2014 as extreme of the extremes writes,”…… The flood vulnerability scenario in the Jehlum basin has worsened during the last few decades as most of the Wetlands that used to act as sponge during flooding, have urbanised and converted into concrete landscape in the entire Kashmir valley.Most of our wetlands and water bodies are fighting a loosing battle for their survival. The functionality of wetlands having strong linkages with hydrological cycle, has got adversely affected due to their encroachment and seasonal changes in the precipitation and runoff attributed to the Climate change. In and around Srinagar only, we have lost 20 wetlands to urban colonies during the last five decades, particularly in the south of Srinagar City. The impervious concrete surfaces in the city have increased from 34% in 1990 to more than 65% in 2010 severally affecting the hydrological processe4s particularly infiltration. Shrinking of most of the Wetlands in Kashmir valley, deforestation, urbanisation of floodplains and siltation of water courses has degraded the ability of our Environment to absorb the excess rainwater and thus increased the vulnerability of the Jehlum basin to flooding.
Commenting on the recent flood, Dr.Asad Rehmani, Director Bombay Natural History Society said,” The disasterous damage caused to life and property could have been minimised if large number of wetlands that once existed in the valley had been preserved. Wetlands act as sponge that retain excess water.” He added that even the British and former Mahraja of Kashmir considered Wular as a buffer for the floods, where surplus water was absorbed.
The background note by Centre for Dialogue and Reconciliation on 2014 Kashmir floods too have opined that the most important reasons for the high magnitude of the observed inundation and loss during the 2014 floods in Kashmir could be attributed to the heavy rainfall events, massive reckless urbanization of the flood plains along both sides of the Jehlum since 1972, Loss of Wetlands, and the reduced drainage capacity of Jehlum due to siltation from the catchment.
I do agree with Prof. Shakil Romshoo that only Flood zonation plans shall help the Government to develop safe housing policy and help to protect the flood plains and Wetlands that used to act as reservoirs of water during flooding in the past.
We as Kashmiris should always remember that we have evolved in and around SATISAR and have from times immemorial lived in close relationship and harmony with the water resources, may it be lakes, streams, wetlands or rivers etc and our economy has always been dependent on the water resources.
Protection of Wetlands will not only help in flood control but also help in recharging the ground waters besides ensuring better security by way of increased availability. Despite the fact Central Wetland Regulatory Authority exists at present but it has proved a toothless Authority.