Prof. Iyer noted that nowadays we stop river flows wherever possible, jacket them with embankments, deprive them of space, pollute and contaminate them. We do everything possible to kill the rivers and then spend thousands of crores to revive them and even set up authorities to do so. In this talk on the Yamuna, it is worthwhile to find out why this happens and what can be done to restore the rivers which are in decline and ensure that the other rivers do not fall into the same state.
Prof. Brij Gopal began his presentation by defining rivers as unique and fascinating systems that transform large landscapes displaying their diverse forms. Along its course, the river changes its mood as it roars, rushes, falls to greater depths, and becomes quiet. Rivers are not water storages or conduits, but ecosystems providing valuable goods and services.
What are living rivers? Rivers have several functions.They exhibit homeostasis--the dynamic equilibrium among the living under their everchanging environmental conditions and are resilient. Hence they are living. Rivers are three dimensional dynamic systems dependent on longitudinal, lateral and vertical transfers of material energy and biota. They change over time in response to hydrological and biological processes and human intervention. Hydrology takes an overriding role here. Their ecological integrity lies with the totality of physical, chemical, biological and functional attributes.
Prof Brij Gopal speaking at the Living Rivers Dying Rivers series lecture on Yamuna
River values and attributes
Brij Gopal said that all values of the rivers are derived from the interaction between their five main components--physical structure, floodplain, biota, water quality and water quantity. A river starts dying when any of the five components are affected.
Floodplains are as important to rivers as is bark to trees. River flows are regulated not by humans but by the hydrological cycle. Rivers are an integral part of the hydrological unit, a river basin. They do not drain the catchments but receive runoff from the catchment and carry it forward. Growth and distribution of all aquatic organisms are directly governed by the flow regimes. In floodplains, rivers' lateral interactions become more important than the longitudinal changes. Yamuna and Ganga are alluvial rivers carrying a lot of sediments that have specific characteristics. All alluvial rivers have especially complex channel morphology.
Brij Gopal noted that an interesting feature of the Yamuna is that at its confluence with the Tons it carries less water from the Tons itself after the Giri and Asan meet it. And even downstream, Yamuna (94,400 mcm) carries more water than the Ganga (58,800 mcm) and out of this the Chambal carries a lot (30,500 mcm). Chambal carries more water at the confluence with Yamuna than the Yamuna herself.
Of dams and barrages
Water abstraction through the canal system at Tajewala started in the late 14th century by Feroze Shah Tughlaq. Abstraction systems were built and rebuilt until the Tajewala barrage was built by the British in the 1830s. The high floods of 1924 forced a redesigning of the canal offtake. The Okhla Barrage was built in 1872, following which many barrages and diversions have come up or are being planned.
Brij Gopal discussed the study on Supingadh and Obragad microwatersheds in the Yamuna basin. The investigation of the land use changes between 1970 and 2001 indicated changes in river course and the disappearance of streams. Embankments are harming the river. He also discussed the hydroelectric projects in the Upper Yamuna basin. Dams will be created right up to the glaciers. If these dams are constructed, the entire upper basin will be destroyed and the river may not continue to flow.
Mr. Manoj Misra speaking at the Living Rivers Dying Rivers series lecture on Yamuna
The river is now officially dead and there is absence of natural river water after it flows through Delhi as per a Central Pollution Control Board (CPCB) report. Delhi is the source of 90 per cent of all pollution in the river and has converted all its 22 little tributaries into sewer and waste water drains. It has set a bad example of flood plain encroachments, mainly by the agencies of the state themselves.
After the construction of Hathni Kund Barrage, almost 90 percent of the natural fresh water has been taken away for irrigation, industrial development and drinking. This is grossly mismanaged with little or no accountability. In most places, the river is a listless morass of human, industrial and agricultural wastes, literally an open sewer. The stretch in New Delhi is the worst and the city’s sewage contributes 70 percent of the pollution to the river Yamuna while it has only two per cent of the length.
The founder basin of this 1400 km long river is very small. There is the chicken neck and practically no tributary worth notice. Misra said that there is a need to take extreme care in case of such basins because there is very little freshwater on the cards. This is the most threatened part of the river. Unfortunately, all the big cities like Delhi, Agra and Mathura are on the chicken neck. Misra noted that though millions have depended on Yamuna since eternity and still do, the river right now is nothing more than a sewage drain. The river actually ceases to exist beyond Wazirabad Barrage in New Delhi.
A tool to measure river health
PEACE has worked on developing a Peoples River Health Index (PRHI). It is a user friendly tool to assess the current state of a river's health. Participatory identification of ‘actions’ are needed for improving the rivers health. The four principles of the tool are:
- Ensure that the catchment of the river is intact (Ct)
- There is ‘adequate’ flow in the river (Qn)
- There is ‘clean’ water in the river (Qu)
- River is intact in terms of its shape, size and character (Rz).
Consultations were held during the testing of this tool. Using the tool it was found that of the 13 places, the river is dying at three places, healthy at two places and sick at eight places.
How to revive the river?
Most debates around rivers in the past have been around this or that dam or how to ‘clean’ a river. Brij Gopal suggested restoration of habitats, flow regimes, riparian floodplain areas, catchments and prevention of pollution.That a river is a unique and exceptional ecological entity with irreplaceable ecosystem services has been little understood or debated and hence rarely becomes a part of any serious policy dialogue and action, according to Manoj Misra. His suggestions included:
- Minimum ecological flow: Lack of dilution capacity is a problem and therefore minimum ecological flow is the utmost necessity. Flows are needed to maintain the river regime and enable it to purify itself. While river Yamuna is gasping for breath the Western Yamuna Canal is very happy as all the river water is in the canal.
- Welfare of all tributaries: Unless welfare of all the tributaries is addressed there can be no basin level plan for any river. Water is not river, most ills facing our rivers emanate from this deep seated confusion. River has life, shape, size, character and dynamism; thus restoration would need to address them all.
- Amount of water diverted: When most of diverted water returns unpolluted to the river e.g., Dakhpathar barrage, 25-35 percent must flow on a daily basis in the river. When water is diverted for good, or returns in a polluted form, e.g., Hathnikund Barrage, 50 per cent must flow on a daily basis in the river. River must flow free of all barrages (3-4 days) per month during lean season between January to June.
- Secure flood plains, he stated that the River Regulation Zone (RRZ) notification that declares 100 year return floodplains as ‘eco-sensitive zone’ and prohibits raising of any structure of commercial, residential and industrial nature should be put into practice.
- National river policy: There is a need for this, independent of the national water policy. The national river conservation directorate needs to go beyond river ‘cleaning’ and the thrust should be on river basins. River sanctuaries can be carved out like the one in Chambal.
- Government action: It is a myth that the Central Government is powerless. Entry 56 in List 1 of Seventh Schedule empowers it adequately to deal with interstate rivers. The 1994 MoU between the riparian states of Yamuna must be revisited. Furthermore, there is need for an emphasis on water ‘demand’ management rather than water ‘supply’ management.
The lecture in various parts can be viewed at Youtube in the playlist below