Central Water Commission (CWC) is the only agency doing flood forecasting in India. CWC’s Flood Forecasting (FF) is available on its website[I]. In this article we have given an overview of CWC’s flood forecasting and monitoring sites in East India. It includes state wise list of CWC’s Level Forecast, Inflow Forecast and level monitoring sites in East India. Similar report has been published for North India[II] and North East India[III] and we hope to publish reports covering other regions of India soon. East India includes five states: Bihar, Jharkhand, Chhatisgarh, Odisha and W Bengal.
Bihar Unsustainable sand mining causing floods in West Champaran The sand mining in the rivers of West Champaran was causing unmitigated floods in the region, year after year but the govt failed to respond.
– West Champaran district also sees many floods in the non-monsoon months, many of which go unreported, and often, ignored by flood-relief schemes. The natural explanation for the flash floods is that the region is at the foothills and rivers from the hills of bordering Nepal flow through it. But the floods are not entirely a result of natural phenomena. Over the years, excessive sand mining in the river beds has led to ecological imbalances, making rivers and streams flood and even change their course, wreaking havoc in the villages along their banks.
Central Water Commission is the only agency doing flood forecasting in India. As per CWC’s Flood Forecasting website[I] the Data Flow Map has information about 226 Flood Forecast Sites in the country comprising of 166 Level Forecast Sites and 60 Inflow Forecast Sites. It also monitors 700 Flood sites, information made available through List Based Exploration and Hydrograph View, but no flood forecasting is done for these sites.
In order to better understand the CWC’s flood monitoring and forecasting work, in this article we have given an overview of CWC’s flood forecasting and monitoring sites in East India. It includes state wise list of CWC’s Level Forecast, Inflow Forecast and level monitoring sites in East India. Similar report has been published for North India[II] and North East India[III] and we hope to publish reports covering other regions of India too.
Reliable data and information that is both correct and validated on ground, is a pre requisite to understand any feature or activity. And for a river, a constantly evolving and truly complex entity, it becomes even more crucial. The wellness quotient of rivers, their present health status, all these and more can only be understood, once we have the rudimentary knowledge of the river and the basins that they form.
A step in this direction has been taken up by the India WRIS (Water Resources Information System) project (A joint venture between Central Water Commission and Indian Space Research Organisation), that aims “to provide a ‘Single Window Solution’ for water resources data & information in a standardized national GIS framework”[i]. This project has generated 20 basin level reports that share important information on the salient features of the basin, their division into sub basins, the river systems that flow through it and the water resource structures, such as irrigation & hydro electric projects in the basin. Another crucial inclusion is the length of major rivers in each basin, which have been GIS calculated (Geographic information system)[ii] and in a few reports the place of origin of the rivers too is mentioned. (Ganga Basin Report). This is an improvement over the earlier documented river lengths that included the canal length along with the river lengths, in earlier CWC documents (e.g. water and related statistics)!
The Basin reports include basin level maps which also show the proposed inter basin transfer links and the major water resource structures & projects. Individual maps at the sub basin level mark the rivers & their watersheds. The report gives details on the topography, climate, the land use / land cover area , and also the information on hydro meteorological stations like groundwater observation cells, flood forecasting sites and even water tourism sites.
These reports can be downloaded from the WRIS site.[iii]
The reports are an attempt to document the water resources data & information for a better and more integrated planning, at the basin level. A table below tabulates some important parameters from the 20 basin reports.
Missing Dams! It can be seen from table on next page that total number of dams in all the 20 basins come to 4572. Assuming that this includes all the completed large dams in India by Dec 2013 (WRIS report is dated March 2014), if we look at the number of large dams in India as in Dec 2013 in the National Register of Large Dams (NRLD), the figure is 4845. This leaves a difference of 273 large dams, which are missing from the WRIS list! This seems like a big descripancy. Unfortunately, since NRLD gives only statewise list and does not provide river basin wise list and since WRIS list provides only river basin wise list and does not provide the names of districts and states, it is not possible to check which are the missing dams, but WRIS need to answer that.
Sub Basins These 20 basins have been further delineated into a number of sub basins. The sub basins details include the geographical extent of the sub basin, the rivers flowing in it, the states that they travel through, number and size range of watersheds and also the details of dams, weirs, barrages, anicuts, lifts & power houses, accompanied by maps at this level. The irrigation and hydro electric projects in the area are detailed and mapped for greater convenience. The sub basin list is given here to get a detailed picure.
Indus Basin Sub-basins:
- Beas Sub Basin
- Chenab Sub Basin
- Ghaghar and others Sub Basin
- Gilgit Sub Basin
- Jhelum Sub Basin
- Lower Indus Sub Basin
- Ravi Sub Basin
- Shyok Sub Basin
- Satluj Lower Sub Basin
- Satluj Upper Sub Basin
- Upper Indus Sub Basin
|S. No||River Basin||Major river||No. of sub basins||No. of watersheds||No. of water resource structures||No. of water resource projects|
|1||Indus (Upto border)||Indus (India)||11||497||39||13||18||0||45||59||30||40||21||55|
|c||Barak & others basin||Barak||3||77||4||3||0||0||0||3||0||6||3||3|
|6||Subernarekha||Subernarekha & Burhabalang||1||45||38||4||12||0||0||3||5||34||0||1|
|7||Brahmani & Baitarni||Brahmani & Baitarni||2||79||61||5||4||1||0||1||8||35||4||1|
|14||WFR Tapi to Tadri||Many independent rivers flowing||2||96||219||0||3||0||1||18||13||15||1||12|
|15||WFR Tadri to Kanyakumari||3||92||69||6||6||4||0||29||19||12||7||21|
|16||EFR Mahanadi_ Pennar||4||132||64||5||12||12||0||0||12||46||10||0|
|17||EFR Pennar _ Kanyakumari||4||165||61||2||2||11||0||6||13||33||4||5|
|18||WFR Kutch _ Saurashtra||Luni||6||268||408||1||10||0||0||0||8||100||4||15|
|19||Area of inland drainage in Rajasthan||Many independent rivers flowing||–||–||1||0||0||0||48||0||11||1||1||0|
|20||Minor rivers draining into Myanmar(Burma) & Bangladesh||Many independent rivers flowing||4||54||3||5||0||0||3||–||3||4||1||–|
* Extension, Renovation and Modernization ** Data has been accumulated from the individual Basin Reports from India WRIS[iv]
- Yamuna Lower
- Yamuna Middle
- Yamuna Upper
- Chambal Upper
- Chambal Lower
- Ghaghara confluence to Gomti confluence
- Gandak & others
- Above Ramganaga Confluence
- Bhagirathi & others ( Ganga Lower)
- Upstream of Gomti confluence to Muzaffarnagar
- Kali Sindh and others up to Confluence with Parbati
Brahmaputra Basin It is strange to see that the profile divides this huge basin into just two sub basins, when it could have easily divided into many others like: Lohit, Kameng, Siang, Subansiri, Tawang, Pare, Teesta, Manas, Sankosh, among others.
- Brahmaputra Lower
- Brahmaputra Upper
Barak & Others Basin
- Barak and Others
- Kynchiang & Other south flowing rivers
- Naochchara & Others
- Godavari Lower
- Godavari Middle
- Godavari Upper
- Pranhita and others
- Bhima Lower Sub-basin
- Bhima Upper Sub-basin
- Krishna Lower Sub-basin
- Krishna Middle Sub-basin
- Krishna Upper Sub-basin
- Tungabhadra Lower Sub-basin
- Tungabhadra upper Sub-basin
- Cauvery upper
- Cauvery middle
- Cauvery lower
Subernarekha Basin No sub-basins.
Brahmani & Baitarani Basin
- Mahanadi Upper Sub- basin
- Mahanadi Middle Sub- basin
- Mahanadi Lower Sub- basin
- Pennar Upper Sub-basin
- Pennar Lower Sub-basin
- Mahi Upper Sub-basin
- Mahi Lower Sub-basin
- Sabarmati Upper Sub- basin
- Sabarmati Lower Sub-basin
- Narmada Upper Sub-basin
- Narmada Middle Sub-basin
- Narmada Lower Sub-basin
- Upper Tapi Sub- Basin
- Middle Tapi Sub- Basin
- Lower Tapi Sub- Basin
West flowing rivers from Tapi to Tadri Basin
- Bhastol & other Sub- basin
- Vasisthi & other Sub- basin
West flowing rivers from Tadri to Kanyakumari Basin
- Netravati and others Sub- basin
- Varrar and others Sub- basin
- Periyar and others Sub- basin
East flowing rivers between Mahanadi & Pennar Basin
- Vamsadhara & other Sub- basin
- Nagvati & other Sub- basin
- East Flowing River between Godavari and Krishna Sub- basin
- East flowing River between Krishna and Pennar Sub- basin
East flowing rivers between Pennar and Kanyakumari Basin
- Palar and other Sub-basin
- Ponnaiyar and other Sub-basin
- Vaippar and other Sub-basin
- Pamba and other Sub-basin
West Flowing Rivers of Kutch and Saurashtra including Luni Basin
- Luni Upper Sub-basin
- Luni Lower Sub-basin
- Saraswati Sub-basin
- Drainage of Rann Sub-basin
- Bhadar and other West Flowing Rivers
- Shetrunji and other East Flowing Rivers Sub-basin
Area of inland drainage in Rajasthan Due to very flat terrain and non-existence of permanent drainage network, this basin has not been further sub divided.
Minor rivers draining into Myanmar and Bangladesh
- Imphal and Others sub basin
- Karnaphuli and Others sub basin
- Mangpui Lui and Others sub basin
- Muhury and Others sub basin
Narmada Basin: Some details To understand the compiled information at the basin level, we take a look at the one of the basin level reports, the Narmada Basin Report[v] (dated March 2014) as an illustrative example. An overview of the basin area right at the beginning, gives its geographical location, shape, size, topography, climate & population. This basic relevant information is tabulated in a concise table for easy access, as given below:
River information The major river flowing in the basin, the Narmada River (also called Rewa) that flows through the 3 states of Madhya Pradesh, Maharashtra & Gujarat, its length (1333 km) and the length of its 19 major tributaries out of a total of 41 is given, based on GIS calculations. There is also a clear river network map of the Narmada basin that demarcates the 3 sub basins along with the watersheds, and shows the dams / weirs /barrages and the rivers in the basin.
- Narmada Upper Sub-Basin, with 16 watersheds
- Narmada Middle Sub-Basin, having 63 watersheds
- Narmada Lower Sub-Basin, with 71 watersheds
The surface water bodies details include the size (less than 25 ha to more than 2500 ha) and type (Tanks, lakes, reservoirs, abandoned quarries or ponds) of existing bodies. Nearly 91.8% of these are tanks.
Irrigation Projects The water resource projects in the basin are as follows:
- 21 Major Irrigation Projects
- 23 Medium Irrigation Projects
- 1 ERM Project
- 6 Hydro-Electric Projects
Interestingly description is only of the major and medium irrigation projects, information on minor projects is completely absent. An attempt to include the details of minor irrigation projects would have made the report more useful. The reports seem to not understand the significance of the smaller projects and their importance for the people and in the conext of the River Basin too.
Water resource structures The number and type of big manmade structures in the basin is given. These are a total of 277 dams, 2 barrages, 2 weirs and 4 lifts, of which again the major structures are marked on a map, and details given as in table below. Dams are classified on the basis of storage and purpose they are used for, and the dam numbers are available at sub basin level.
The report gives tabulated data for each of the dams, which is supposed to have name of the river, height, length, purpose, year of commissioning, etc. Since GIS is the strength of ISRO, they could have easily given latitude and longitudes of each dam, but they have not. Shockingly, in case of 186 of the dams, name of the river on which it is built is given as ‘Local Nallah’, and in case of 10 they have left the column blank. This means for nearly 71% (196 out of 277) of the dams they do not even know the name of the river they are build on. This is actually an improvement over the performance of CWC. The CWC’s National Register of Large Dams[vi], we just checked, mentions Narmada only 13 times (for 12 dams of Gujarat and 1 dam of Madhya Pradesh).[vii]
It is well known that Narmada Basin is the theatre of India’s longest and most famous anti dam movement, Narmada Bachao Andolan. The movement involves opposition to Sardar Sarovar, Indira Sagar, Omkareshwar, Maheshwar, Jobat dams, among others. Such social aspects should also form part of any river basin report.
Surface water quality There are 19 surface water quality observation sites in the basin, that collect water data and the report spells out , “As compared to the other rivers, the quality of Narmada water is quite good. Even near the point of origin, the quality of river water was in class ‘C’ in the year 2001 while it was in class ‘B’ in earlier years. As was observed for most other rivers, in case of Narmada also, BOD and Total Coliform are critical parameters.” This shows that even in Narmada Basin, water quality is deteriorating. The statement also remains vague in absence of specifics.
Inter basin transfer links Details of the Par-Tapi-Narmada Link, which is a 401 km long gravity canal and its proposal to transfer 1,350 MCM (Million Cubic metre) of water from ‘surplus rivers’ to ‘water deficit’ areas is given, along with a map. How has the conclusion of surplus or deficit been reached? Does the assessment exhaust all the options including rainwater harvesting, watershed development, groundwater recharge, better cropping patterns and methods, demand side management, optimising use of existing infrastructure, etc? Is this is the least cost option? Does the water balance include groundwater? Who all will be affected by this or even how much land area will be affected by this proposal, there is absolutely no talk of this? No answers in the report.
There’s more to a river There is no information in basin reports on the regulating or statutory bodies that have a say in the basin in the report. However, some information on the existing organisations and inter-state agreements at the various basin level is given at another WRIS location.[viii]
The Basin reports for 20 basins are clearly an asset for understanding and analysing water resource situation. However, there is no mention of the numerous ecological, social and environmental services these rivers provide us with. The demographic details of the basin are available, but there is no information on the flora and fauna, who also need and thrive on the river waters. A good navigation tool for water resource information and river management projects at basin level, nevertheless, for a broader and more comprehensive outlook these reports should have included the following essential aspects too:
- River status: The present water quality & pollution level of the major rivers as well as their tributaries
- River governance: The local committees, civil bodies and institutions that play a role in river basin development
- River safety measures: Effect of the existing and planned river management projects on the state of the river, people and society.
- River ecology: Status of biodiversity, and other ecological aspects of the rivers
Sabita Kausal, SANDRP (email@example.com)
[vii] For more details, see: https://sandrp.wordpress.com/2013/03/14/how-much-do-we-know-about-our-dams-and-rivers/