This document provides an overview of several major rivers in India, including the Ganga, Godavari, Krishna, and Brahmaputra rivers. It discusses the fish diversity found in these river basins, listing the number of fish species identified in various studies of sections and tributaries of the rivers. It also outlines some of the dams, barrages, reservoirs, and other structures built on the rivers, and describes impacts to fisheries and aquatic ecosystems from these constructions. Wildlife sanctuaries and other protected areas located within the river basins are also briefly mentioned.

1. Major Rivers Dams Impacts on
environment with special focus on Inland
Capture Fisheries of India
By:
B. Bhaskar
Fisheries

2. Introduction
• Globally, 6% of all the species, and more than 10%of all animal species, occur
in freshwaters, including 25% of all vertebrates and 40% of the fishes (Balian
et al., 2008).
• Fish contributes faintly more than one half of the total vertebrates with 34300 species. India
contributes to about 7.7% of global fish diversity, of which 1,673 are marine and 994 are
freshwater (Froese & Pauly, 2020).
• Coad and Murray (2006) estimated more than 32,000 valid species of fish on earth included in 85
orders and 536 families and 43% of fishes are freshwater fishes.
• a mighty river like Brahmaputra supports more than 2 million fisher folk, smaller
rivers like Wainaganga in Maharashtra support more than 4 lakh fishermen.
• The fisher folk in India can be termed as the poorest of the poor.
• Most of them live along riparian tracts and catchment areas, largely bereft of
welfare schemes/ programmes
• The current riverine fishery is below subsistence level with an average yield of 0.3
tonne per km, which is about 15% of their actual potential
• Rivers in India are facing multiple problems of severe pollution, over extraction,
encroachment, dams and barrages which cut off the connectivity of the river with its
associated ecosystems, climate change, deforestation in catchment areas, etc.
• According to Central Inland Fisheries Research Institute (CIFRI) “severe and drastic
changes in the entire hydrological cycle of the river by dams and water abstractions
has affected recruitment of most species, especially large carps, which like flowing
water.
• Larger dams are major cause of degradation of aquatic environment and disruption
of livelihood communities dependent upon the fishery along the rivers.

3. • . About 45,000 dams have been built worldwide with elevation of
more than 15 meters and about 73% of them have been built
within the last 50 years.
• The first known dam of the world was built in 2900 BC across the
Nile River to protect the city of Memphis from flood.
• The tallest ever dam (305 meter) of the world is situated in China
on the Yalong Jiang River, followed by the Tehri Dam (261 meter) in
India on the Bhagirathi River near Tehri in Uttarakhand. The
Hirakud dam is the longest dam in India which is about 26 km in
length, built across the Mahanadi River in the state of Odisha
(Dwivedi et al., 2010; Siddique et al.,2017).
• It is estimated that, worldwide, there may be 16.7 million human
made reservoirs with a surface area larger than 0.01 mha (Laehner
et al., 2011).
• India has constructed large number of dams across the country
for generating power and for Irrigation. At present the total
reservoir area in the country is 3.15 mha, out of which small
reservoirs occupy 1.49 mha, followed by large (1.14 mha) and
medium reservoirs (0.52 mha)

4. Freshwater fish diversity in India
Study Area & Number of
Species present
Study Area & Number of Species
present
Study Area & Number of
Species present
Gomti river 56 Koyna river 58 Upper reaches of river Brahmaputra
52
Betwa river 63 Indrayani river 57 Ranganadi river 61
Ganga river 143 Pavana river 59 Siang river 82
Ken river 57 Mutha and Mula river 62 Harike wetlands 37
Yamuna river 112 Mullameri river 14 Pong Dam lake 57
Ghaggar, Yamuna and Ganga 26 River fishes in Western Ghat Mountains of
Penisular India 60
Basantar river 32
Jamner river, 27 Bhadra river 56 Ujh river 42
Tawa river middle stretch 57 Adan and Kathani river of Godavari basin 47 Chenab in J.K. 5
Narmada river in Western Zone 51 Godavari river 26 Beas river in H.P 6
Dudhi river 19 Cauvery river 37 Ornamental fish fauna of Himachal
Pradesh 58
wan river 21 Brahmaputra river 141 Beas, Ravi, Sutlej in H.P. 61
Barna river 33 Dihing river 50 Similipal Biosphere Reserve, Odisha
66

5. Study Area & Number of Species
present
Study Area&Number of Species present
Highland of Himalaya, Central
Highland and the Western Ghats
367 (266 in Himalayan, 155 in
Western ghat & 95 in central
Highland)
Kangsabati reservoir 39
Fish Fauna of Himachal Pradesh 104 Tighra reservoir, Gwalior 40
Fish fauna of Himachal Pradesh 81 Manjeera reservoir, Telangana 57
Rakchham – chhitkul wildlife
sanctuary H.P. 2
Gobind Sagar Dam 46
Das et al.,9 with a total of 190 fish
species (182 indigenous and
8exotics) belonging to 133 genera,
62 families and 23 orders from
upper Ganga (Harsil) to the
Hooghly estuary (Fraserganj)
during 2016-2019
Thotapalli and Gottabarrage reservoir 3
1
Sone Lake, Assam 69
Kamalpur Lake, Telangana 25 1
Kumaon Himalaya 10
Western Ghats of India 288
North East India along with Himalayan
and Indo Burma Biodiversity hotspots
422

6. Case study Impacts of Dams on Fisheries in Krishna River
Basin
• The following are few other wildlife
sanctuaries located in the Krishna basin.
• Nagarjunsagar-Srisailam Tiger Reserve
• Rollapadu Wildlife Sanctuary
• Bhadra Wildlife Sanctuary
• Ghataprabha Bird Sanctuary
• Gudavi Bird Sanctuary
• Koyna Wildlife Sanctuary
• Radhanagari Wildlife Sanctuary
• Great Indian Bustard Sanctuary
• Chandoli National Park
• Kudremukh National Park
• Kasu Brahmananda Reddy National Park
• Mahavir Harina Vanasthali National Park
• Mrugavani National Park
• Pakhal Wildlife Sanctuary
• Ranibennur Blackbuck Sanctuary
• Shettihalli Wildlife Sanctuary
• Daroji Sloth Bear Sanctuary, Bellary
 The following are few other waterfalls
located in the river basin
• Ethipothala on Chandravanka river which is
the tributary of river Krishna river
• Godchinamalaki on Markandeya river a
tributary of Ghataprabha
• Gokak on Ghataprabha
• Mallela Theertham
• There are many dams constructed across the Krishna
river
• Dhom Dam
• Hippargi barrage
• Almatti Dam
• Narayanpur Dam
• Bhima Dam
• Jurala Dam
• Srisailam Dam
• Nagarjuna Sagar Dam
• Nagarjuna Sagar tail pond
• Pulichinthala Dam
• Prakasam Barrage
• Tungabhadra Dam
• Rajolibanda barrage
• Sunkesula barrage
Srisailam Dam Nagarjuna Sagar Dam
Almatti Dam

7. Godavari River
• The Krishna Godavari Basin is one of the main nesting sites of the endangered olive
ridley sea turtle. Godavari is also a home to the endangered fringed-lipped carp
(Labeo fimbriatus).
• The Coringa mangrove forests in the Godavari delta are the third largest mangrove
formation in the country. Part of this has been declared as the Coringa Wildlife
Sanctuary, renowned for reptiles. They also provide an important habitat to a wide
variety of fish and crustaceans. These forests also act as barriers against cyclones,
tropical storms, and storm surges, thus protecting the nearby villages.
• The Jayakwadi Bird Sanctuary is another haven for birds located near the town of
Paithan spread across the back waters of the NathSagar Reservoir formed by
impounding the Godavari by the massive Jayakwadi Dam. Its 341 km2 area is dotted
by islands within the reservoir which serve as nesting sites for the birds.
• The Nandurmadmeshwar Bird Sanctuary is located along the back waters of the
Godavari river near Nashik at its confluence with Kadva River. It is known as the
Bharatpur of Maharashtra for the wide diversity of bird life that it harbours.
• The following are few other wildlife sanctuaries located in the river basin:
• Bor Wildlife Sanctuary
• Eturnagaram Wildlife Sanctuary
• Gautala Wildlife Sanctuary
• Indravati National Park
• Kanger Ghati National Park
• Kawal Wildlife Sanctuary
• Kinnerasani Wildlife Sanctuary
• Kolleru Wildlife Sanctuary
• Manjira Wildlife Sanctuary
• Nagzira Wildlife Sanctuary
• Navegaon National Park
• Painganga Wildlife Sanctuary
• Papikonda Wildlife Sanctuary
• Pench National Park
• Pocharam Forest & Wildlife Sanctuary
• Pranahita Wildlife Sanctuary
• Tadoba Andhari Tiger Project
• Tipeshwar Wildlife Sanctuary
• Duduma Waterfalls is 175 metres (574 ft) high and one of the highest waterfalls in
southern India. It is located on the Sileru River which forms boundary between
Andhra Pradesh and Odisha states. The following are a few other waterfalls located
in the river basin:
• Bogatha
• Chitrakoot
• Kuntala
• Pochera
• Sahastrakunda
• Teerathgarh
• following are the few dams located in the river basin:
• Gangapur Dam: This is a large earth fill dam with gross water storage of 215.88
million cubic metres,[41] and located 10 km (6.2 mi) upstream from Nashik city. The
reservoir known as the Gangapur Bandh Sagar provides drinking water to the Nashik
city and also supplies water to the thermal power station situated downstream
at Eklahare.
• Jayakwadi Dam: Located near Paithan, it is one of the largest earthen dams in India.
This dam was built to address the dual problems of flooding along the banks, during
monsoon months, and that of drought, rest of the year, in the Marathwada region.
Two 'left' and 'right' canals provide the irrigation to fertile land up to Nanded district.
This dam has contributed to industrial development
of Aurangabad and Jalna, Maharashtra.[42] Majalgaon Dam is also constructed under
Jayakwadi stage 2 to expand the irrigation potential further
in Parbhani, Nanded and Beed districts.
• Vishnupuri barrage: Asia's Largest Lift Irrigation project, the Vishnupuri
Prakalp[43] has been constructed on the river at a distance of 5 km (3.1 mi) from the
city Nanded.
• Ghatghar Dam was built for hydro power generation by diverting the water of
Pravara tributary outside Godavari river basin to a west flowing river which joins
Arabian sea.
• Upper Vaitarna reservoir was built across west flowing Vaitarna river merging some
part of Godavari river catchment area. Godavari water impounded in this reservoir is
diverted outside the river basin for Mumbai city drinking water supply after
generating hydro power.
• Sriram Sagar Dam: This is another multipurpose project on the Godavari River on the
borders of Adilabad and Nizamabad District. It is near the town of Pochampadu,
60 km away from Nizamabad. It has been described by The Hindu as a "lifeline for a
large part of Telangana".[44] It serves the irrigation needs
in Karimnagar, Warangal, Adilabad, Nalgonda, and Khammam districts and also
generates power.
• Sir Arthur Cotton Barrage was built by Sir Arthur Cotton in 1852. It got damaged in
1987 floods, and rebuilt as a barrage cum roadway soon after and named after him.
The roadway connects Rajamahendravaram in East Godavari and Vijjeswaram in
West Godavari. The irrigation canals of this barrage also form part of National
Waterway 4.

8. Godavari River
• Distributed in State:
Maharashtra, Telangana, Andhra
Pradesh, Chhattisgarh, OdishaRegionWest
India and South India Physical characteristic:
sSource • locationBrahmagiri
Mountain, Trimbakeshwar, Nashik, Maharashtra,
India • coordinates19°55′48″N 73°31′39″E • elevati
on920 m (3,020 ft)MouthBay of Bengal • location
• Antarvedi, Konaseema district Andhra Pradesh,
India • coordinates
• 17°0′N 81°48′E • elevation
• 0 m (0 ft)Length1,465 km (910 mi)Basin
size312,812 km2 (120,777 sq mi)Discharge • locati
onGodavari Delta, Bay of
Bengal • average3,505 m3/s
(123,800 cu ft/s)Discharge • locationRajahmundry
(80 km upstream of mouth; Basin size:
308,946 km2 (119,285 sq mi) • average(Period:
1998–2022)3,626.1 m3/s
(128,050 cu ft/s)[2]Discharge • locationPolavaram
(1901–1979)[3] • average3,061.18 m3/s
(108,105 cu ft/s) • minimum7 m3/s
(250 cu ft/s) • maximum34,606 m3/s
(1,222,100 cu ft/s)Basin featuresTributaries • leftB
anganga, Kadva, Shivana, Purna, Kadam, Pranahita,
Indravati, Taliperu, Sabari • rightNasardi, Pravara, S
indphana, Manjira, Manair, Kinnerasani
Bhadrachalam Temple during 2005 floods

9. Ganga River
• CountryI:
• India (as Ganga), Bangladesh (as Padma)
• CitiesUttarakhand: Rishikesh, Haridwar Uttar
Pradesh: Bijnor,Fatehgarh, Kannauj, Hardoi, Bithoor, Kasganj, Kanpur, Prayagraj, Mirz
apur, Varanasi, Ghazipur, Ballia, Lucknow (Gomti tributary), Farrukhabad, Narora
• Bihar:Begusarai, Bhagalpur, Patna, Vaishali, Munger, Khagaria, Katihar
• Jharkhand: Sahibganj,
WestBengal: Murshidabad, Palashi, Nabadwip, Shantipur, Kolkata, Serampore, Baran
agar, Diamond Harbour, Haldia, Budge Budge, Howrah, Uluberia, Barrackpore
• Delhi: (Yamuna) tributary Rajshahi Division: Rajshahi, Pabna, Ishwardi
• Dhaka Division: Dhaka, Narayanganj, Gazipur, Munshiganj, Faridpur
• Chittagong Division: Chandpur, Noakhali
• Barisal Division: BholaPhysical characteristicsSourceConfluence
at Devprayag, Uttarakhand of the Alaknanda river (the source
stream in hydrology because of its greater length) and the Bhagirathi river (the
source stream in Hindu tradition). The headwaters of the river
include: Mandakini, Nandakini, Pindar and the Dhauliganga, all tributaries of the
Alaknanda.[1] • locationDevprayag, the beginning of the main stem of the
GangesMouthBay of Bengal • location
• Ganges DeltaLength2,525 km (1,569 mi)[2]Basin
size1,999,000 km2 (772,000 sq mi)[3]Discharge • locationMouth of the
Ganges (Ganges-Brahmaputra-Meghna; Basin size
1,999,000 km2 (772,000 sq mi), Bay of Bengal[3] • average38,129 m3/s
(1,346,500 cu ft/s)[4] to43,900 m3/s (1,550,000 cu ft/s)[3]
• 1,389 km3/a (44,000 m3/s)Discharge • locationGanges Delta, Bay of
Bengal • average18,691 m3/s (660,100 cu ft/s)[3]Discharge • locationFarakka
Barrage[4] • average16,648 m3/s (587,900 cu ft/s) • minimum180 m3/s
(6,400 cu ft/s) • maximum70,000 m3/s
(2,500,000 cu ft/s)Basin featuresTributaries • leftRamganga, Garra, Gomti, Tamsa Gh
aghara, Gandak, Burhi
Gandak, Koshi, Mahananda, Brahmaputra, Meghna • rightYamuna, Tamsa (also
known as Tons
River), Karamnasa, Sone, Punpun, Falgu, Kiul, Chandan, Ajay, Damodar, Rupnarayan
• Dams and barrages
• A major barrage at Farakka was opened on 21 April 1975,[107] It is located close to
the point where the main flow of the river enters Bangladesh, and the tributary
Hooghly (also known as Bhagirathi) continues in West Bengal past Kolkata. This
barrage, which feeds the Hooghly branch of the river by a 42 km (26 mi) long feeder
canal, and its water flow management has been a long-lingering source of dispute
with Bangladesh.[108] Indo-Bangladesh Ganges Water Treaty signed in December
1996 addressed some of the water sharing issues between India and
Bangladesh.[107] There is Lav Khush Barrage across the River Ganges in Kanpur.
• Tehri Dam was constructed on Bhagirathi River, a tributary of the Ganges. It is
located 1.5 km downstream of Ganesh Prayag, the place where Bhilangana meets
Bhagirathi. Bhagirathi is called the Ganges after Devprayag.[109] Construction of the
dam in an earthquake-prone area[110] was controversial.[111]
• Bansagar Dam was built on the Sone River, a tributary of the Ganges for both
irrigation and hydroelectric power generation.[112] Ganges floodwaters along with
Brahmaputra waters can be supplied to most of its right side basin area along with
central and south India by constructing a coastal reservoir to store water on the Bay
of Bengal sea area
• Fisheries: estimated that about 350 fish species live in the entire Ganges drainage,
including several endemics.[123] In a major 2007–2009 study of fish in the Ganges
basin (including the river itself and its tributaries, but excluding the Brahmaputra and
Meghna basins), a total of 143 fish species were recorded, including 10 non-
native introduced species.[124] The most diverse orders are Cypriniformes (barbs and
allies), Siluriformes (catfish) and Perciformes (perciform fish), each comprising about
50%, 23% and 14% of the total fish species in the drainage.[124]
• There are distinct differences between the different sections of the river basin,
but Cyprinidae is the most diverse throughout. In the upper section (roughly
equalling the basin parts in Uttarakhand) more than 50 species have been recorded
and Cyprinidae alone accounts for almost 80% those, followed by Balitoridae (about
15.6%) and Sisoridae (about 12.2%).[124] Sections of the Ganges basin at altitudes
above 2,400–3,000 m (7,900–9,800 ft) above sea level are generally without fish.
Typical genera approaching this altitude
are Schizothorax, Tor, Barilius, Nemacheilus and Glyptothorax.[124] About 100 species
have been recorded from the middle section of the basin (roughly equalling the
sections in Uttar Pradesh and parts of Bihar) and more than 55% of these are in
family Cyprinidae, followed by Schilbeidae (about 10.6%) and Clupeidae (about
8.6%).[124] The lower section (roughly equalling the basin in parts of Bihar and West
Bengal) includes major floodplains and is home to almost 100 species. About 46% of
these are in the family Cyprinidae, followed by Schilbeidae (about 11.4%)
and Bagridae (about 9%).

10. Indus River System
• CountryChina, India, Pakistan
Sovereignty in the Kashmir region is disputed.[2]States or
provincesTibet Autonomous Region, Ladakh, Gilgit-
Baltistan, Khyber Pakhtunkhwa, Punjab,
and SindhCitiesLeh, Skardu, Dasu, Besham, Thakot, Swabi,
Dera Ismail
Khan, Mianwali, Bhakkar, Sukkur, Hyderabad, KarachiPhysic
al characteristicsSourceLake
Manasarovar[3] • locationTibetan PlateauSource
confluence • locationShiquanhe, Ngari Prefecture, Tibet
Autonomous Region, People's Republic of
China • coordinates32°29′54″N 79°41′28″E • elevation4,25
5 m (13,960 ft)MouthArabian Sea (primary), Rann of
Kutch (secondary) • location
• Indus River Delta (primary), Pakistan
Kori Creek (secondary), India • coordinates
• 23°59′40″N 67°25′51″E • elevation
• 0 m (0 ft)Length3,180 km (1,980 mi)[4]Basin
size1,120,000 km2 (430,000 sq mi)[4]Discharge • locationIn
dus Delta, Arabian Sea, Pakistan • average5,533 m3/s
(195,400 cu ft/s)[5] • minimum1,200 m3/s
(42,000 cu ft/s) • maximum58,000 m3/s
(2,000,000 cu ft/s)Discharge • locationSukkur • average5,
673.486 m3/s
(200,357.3 cu ft/s)[6]Discharge • locationMithankot • aver
age5,812.326 m3/s
(205,260.4 cu ft/s)[6]Discharge • locationTarbela
Dam • average2,469 m3/s
(87,200 cu ft/s)Basin featuresTributaries • leftZanskar
River, Suru River, Soan River, Panjnad River, Ghaggar-Hakra
River, • rightShyok River, Hunza River, Gilgit River, Swat
River, Kunar River, Kabul River, Kurram River, Gomal
River, Zhob River

11. Indus River Dams

12. Indus River Dams

13. Indus River Dams

14. Tributaries and Major Fishes of Indus River system
• Tributaries of Indus River system
• Gar River
• Gilgit River
• Gomal River
• Haro River
• Hunza River
• Kabul River
• Kunar River
• Kurram River
• Panjnad River
• Chenab River
• Jhelum River
• Ravi River
• Satluj River
• Beas River
• Shyok River
• Soan River
• Dras River (or Shingo River)
• Swat River
• Zanskar River
• Luni river
• Zhob River
• he Indus River basin has high diversity, being the home of more than
180 freshwater fish species,[45] including 22 which are found nowhere
else.[41] Fish also played a major role in earlier cultures of the region,
including the ancient Indus Valley Civilisation where depictions of fish
were frequent. The Indus script has a commonly used fish sign, which in
its various forms may simply have meant "fish", or referred to stars or
gods.
• In the uppermost, highest part of the Indus River basin there are
relatively few genera and
species: Diptychus, Ptychobarbus, Schizopyge, Schizopygopsis and Schizo
thorax snowtrout, Triplophysa loaches, and the
catfish Glyptosternon reticulatum.[45] Going downstream these are
soon joined by the golden mahseer Tor putitora (alternatively T.
macrolepis, although it often is regarded as a synonym of T. putitora)
and Schistura loaches. Downriver from around Thakot, Tarbela,
the Kabul–Indus river confluence, Attock Khurd and Peshawar the
diversity rises strongly, including many cyprinids
• (Amblypharyngodon, Aspidoparia, Barilius, Chela, Cirrhinus, Crossoch
eilus, Cyprinion, Danio, Devario, Esomus, Garra, Labeo, Naziritor, Oste
obrama, Pethia, Puntius, Rasbora, Salmophasia, Securicula and Systo
mus), true loaches (Botia and Lepidocephalus), stone loaches
(Acanthocobitis and Nemacheilus), ailiid catfish (Clupisoma), bagridae
catfish (Batasio, Mystus, Rita and Sperata), airsac catfish
(Heteropneustes), schilbid catfish (Eutropiichthys), silurid catfish
(Ompok and Wallago), sisorid catfish
(Bagarius, Gagata, Glyptothorax and Sisor), gouramis (Trichogaster),
nandid leaffish (Nandus), snakeheads (Channa), spiny eel
(Macrognathus and Mastacembelus), knifefish (Notopterus), glassfish
(Chanda and Parambassis), clupeids (Gudusia), needlefish
(Xenentodon) and gobies (Glossogobius), as well as a few introduced
species.[45] As the altitude further declines the Indus basin becomes
overall quite slow-flowing as it passes through the Punjab Plain.
Major carp become common, and chameleonfish (Badis), mullet
(Sicamugil) and swamp eel (Monopterus) appear.[45] In some upland
lakes and tributaries of the Punjab region snow trout
and mahseer are still common, but once the Indus basin reaches its
lower plain the former group is absent and the latter are
rare.[45] Many of the species of the middle sections of the Indus
basin are also present in the lower. Notable examples of genera that
are present in the lower plain but generally not elsewhere in the
Indus River basin are the Aphanius pupfish, Aplocheilus killifish, palla
fish (Tenualosa ilisha), catla (Labeo catla), rohu (Labeo rohita)
and Cirrhinus mrigala.[45] The lowermost part of the river and its
delta are home to freshwater fish, but also several brackish and
marine species.[45] This includes pomfret and prawns. The large delta
has been recognized by conservationists as an important ecological
region. Here, the river turns into many marshes, streams and creeks
and meets the sea at shallow levels.
• Palla fish (Tenualosa ilisha) of the river is a delicacy for people living
along the river. The population of fish in the river is moderately high,
with Sukkur, Thatta, and Kotri being the major fishing centres – all in
the lower Sindh course. As a result, damming and irrigation have
made fish farming an important economic activity.

15. Noticed Impacts at Indus River due to habitat changes
• The Indusis home to 25 amphibian species
and 147 fish species of which 22 are found
nowhere else in the world.
• It harbours the endangered Indus River
Dolphin, one of the world’s rarest mammals,
says a WWF report called World’s Top 10
Rivers at Risk.
• Engineering projects dramatically changed
the landscape along the Indus in the 1940s,
with the constriction of barrages and
transfer channels to irrigate farmland; and
dams for hydroelectric power, irrigation and
flood control.
• The Kotri barrage near Hyderabad is the one
nearest to the sea.
• Mangroves provide an important habitat for
many species now under threat. The famous
green turtles are found in the delta near
Karachi.
• The area is also the habitat for at least 138
bird species, 34 animal species, 24 reptile
species and 200 fish species. Migratory birds
also use these coastal wetlands as their
habitat
• Endemic Indus dolphin, fish species
including Indus Baril, Indus Garua and
Golden Mahaseer are threatened due to
reduced water flows in theIndus.
• Several snake-head fishes also live here,
including the giant snake-head (Channa
marulius).
• Several fish species, such as Hilsa Shad,
return from theArabian Sea every
monsoon to spawn in freshwater. But
reservoirs, barrages and canals have
blocked their way upstream.
• This fish – known locally as Pallo and
prized all over South Asia for its taste –
once accounted for 70% of the fish catch
during the four months of the
monsoon. At present it barely constitutes
15% of the fish catch in theIndus delta

16. Mahanadi River system
• Mahanadi drains an area of about
1,32,000 km2 inChhattisgarh, Odisha,
Jharkhand and Maharashtra,with total
length of 860 km (Singh et al., 2013).
The principal tributaries of Mahanadi
are the Jonk,Sheonath, Hasdeo, Mand,
Ib, Ong and Tel.
• A total of121 fish species from 21
orders, 43 families and 85 genera
wererecorded from the river.
• Cypriniformes represented by 49
species, wasfound to be the most
dominant order (40%) followed by
Siluriformeswith 23 species (19%).
• Cyprinidae was the richest family (33
species)followed by Danionidae (11
species) and Bagridae (7 species).
• Out of121 fish species reported, 66
species were food fishes, 22
hadornamental importance while 33
species had both food and ornamental
importance.
• Dams and reservoirs: The major
reservoirs which are larger than 2,500
ha area located in the Mahanadi basin
are the Hirakud reservoir, Hasdeo-
Bango dam, Ravishankar Sagar,
Tandula and Dudhawa dams. Most of
these dams were built for the purpose
of irrigation. However, due to an
increasing presence of industries in
the area, especially in Chhattisgarh,
there are conflicts over the allocation
of water between irrigation and
industries. The salient features of
these reservoirs are mentioned in
Table 3, while Figure 19 explains the
course of the river with major
irrigation projects.

17. Tapti River
• The Tapti River (or Tapi) is a river
in central India located to the south
of the Narmada river that flows
westwards before draining into
the Arabian Sea. The river has a
length of around 724 km (450 mi)
and flows through the states
of Maharashtra, Gujarat and Madhya
Pradesh
• State:
MadhyaPradesh, Maharashtra,Gujarat
Physical characteristics Source
Multai, Madhya Pradesh Mouth Gulf of
Khambhat (Arabian Sea) • location
• Dumas, Surat, Gujarat length724 km
(450 mi)approx.Basin size62,225 square
kilometres
(24,025 sq mi)Discharge • locationDum
as Beach • average489 m3/s
(17,300 cu ft/s) • minimum2 m3/s
(71 cu ft/s) • maximum9,830 m3/s
(347,000 cu ft/s)Basin featuresTributari
es • left Girna, Nesu, Amravati, Buray,
Panjhara, Bori, Waghur, Purna, Mona,
Sipna • rightVaki, Aner, Arunawati,
Gomai
• important projects, namely Hathnur
Dam of Upper Tapi Project, Kakrapar
weir and Ukai Dam of Ukai Project,
Girna Dam and Dahigaon Weir of Girna
Project,
Prakasha Barage on Tapti River, at Prakasha

18. Narmada River
• The Narmada basin, hemmed
between Vindhya and Satpura ranges, extends over
an area of 98,796 km2 (38,145.3 sq mi) and lies on
the northern extremity of the Deccan Plateau. The
basin covers large areas in the states of Madhya
Pradesh (82%), Gujarat (12%) and a comparatively
smaller area in Maharashtra (4%) and in
Chhattisgarh (2%). 60% of the basin is made up of
arable land, 35% is forest cover and 5% is made up
of other types of land such as grassland or
wasteland. In the entire course of the river of
1,312 km (815.2 mi), there are 41 tributaries, out of
which 22 are from the Satpura range and the rest on
the right bank are from the Vindhya range.
Dhupgarh (1,350 m), near Pachmarhi is the highest
point of the Narmada basin.
• As one of the 30 dams planned on river Narmada,
the Sardar Sarovar Dam is the largest structure to be
built. It is the second largest concrete dam in the
world in terms of the volume of concrete used in its
construction, after the Grand Coulee Dam across
the Columbia River, US.[39][40] It is a part of the
Narmada Valley Project, a large hydraulic
engineering project involving the construction of a
series of large irrigation and hydroelectricity multi-
purpose dams on the Narmada River. After a
number of cases before the Supreme Court of
India (1999, 2000, 2003), by 2014 the Narmada
Control Authority had approved a series of changes
in the final height and the associated displacement
caused by the increased reservoir, from the original
80 m (260 ft) to a final 163 m (535 ft) from
foundation
• State: Madhya
Pradesh, Maharashtra, GujaratCityNarmadapuram,
Budhni, Jabalpur, Dindori, Narsinghpur Harda, Man
dhata, Omkareshwar, Barwaha, Mandleshwar, Mah
eshwar, Mandla, Bharuch, Rajpipla, Sinor (Vadodar
a District), Dabhoi (Vadodara
District), Karjan (Vadodara
District), DharampuriPhysical characteristicsSource
Narmada Kund • locationVindhyachal
Parvat Amarkantak Plateau, Anuppur
district, Central India, Madhya
Pradesh • coordinates22°40′0″N 81°45′0″E • elevat
ion1,048 m (3,438 ft)MouthGulf of
Khambhat (Arabian Sea) • location
• Bharuch District, Gujarat • coordinates
• 21°39′3.77″N 72°48′42.8″E • elevation
• 0 m (0 ft)Length1,312 km
(815 mi)approx.Discharge • average1,447 m3/s
(51,100 cu ft/s)Discharge • locationGarudeshwar[1]
• average1,216 m3/s
(42,900 cu ft/s) • minimum10 m3/s
(350 cu ft/s) • maximum11,246 m3/s
(397,100 cu ft/s)Basin featuresTributaries • leftKha
rmer, Burhner, Banjar, Temur, Sanair (Saner),
Sher, Shakkar, Dudhi, Sukhri, Tawa, Hather, Ganjal,
Ajnal, Machak, Chhota Tawa, Kaveri (MP), Khurkia,
Kunda, Borad, Deb, Goi, Karjan • rightSilgi, Balai,
Gaur, Hiran, Biranjo, Tendoni, Barna, Kolar (MP),
Sip, Jamner, Chandrakeshar, Khari, Kenar, Choral,
Karam, Man, Uri, Hathni, Orsang

19. Narmada River system
• A total of 196 species from both freshwater and
brackish water habitats, under 14 orders, 51
families, and 126 genera.
• The order Cypriniformes represented the highest
diversity with 78 species (i.e., 39.8%) followed by
Perciformes (47 species), Siluriformes (32 species),
Clupeiformes (15 species), etc. As per the IUCN
Red List category, the maximum number of species
are under Least Concern (129), followed by Not
Evaluated (36), Near Threatened (14), Data
Deficient (11), Vulnerable (4), and Endangered (2).
• The species Tor khudree and Tor putitora were
found Endangered in the system.
• Out of 196 finfish species, 77 are food fishes, 33
having both ornamental and food fish value, 21 are
truly ornamental value, and 31 as sports fishes.
• Habitat wise distribution of the fishes indicates
that 79 species are truly freshwater and 3 species
are truly marine, while 58 species range between
freshwater and brackish water habitats, 21
between brackish water and marine habitats and
35 species range from freshwater to marine
habitats.

20. World scenario om major impacts of dams on Capture fishes
• The research assembled data on the geographic range of
10,000 fish species, and checked those tropical species
against the location of 40,000 existing dams and 3,700 dams
that are either being built or planned for the near future.
• Scientists found that biodiversity hotspots including the
Amazon, Congo, Salween and Mekong watersheds are likely
to be hard hit, with river fragmentation potentially averaging
between 25% and 40% due to hydropower expansion
underway in the tropics.
• Dams harm fish ecology via river fragmentation, species
migration prevention, reservoir and downstream
deoxygenation, seasonal flow disruption, and blockage of
nurturing sediments. Drastic sudden fish losses due to dams
can also destroy the commercial and subsistence livelihoods
of indigenous and traditional peoples.

21. Three Gorges Dam on the Yangtze River
(Image by Le Grand Portage)

22. Fish responses to River Dams/impoundment
• Fish responses to river impoundment from the
perspective of functional traits. A functional trait is
any feature of an organism that affects performance
or fitness, including those related to food
acquisition (e.g. body size, mouth size and position),
mobility and habitat use (e.g. body size and shape,
fin size and position), metabolism (e.g.
thermoregulation, salinity tolerance, hypoxia
tolerance), reproduction (e.g. reproductive effort,
parental investment in individual offspring), and
defense tactics (e.g. crypsis, presence of armor or
spines), among others .
• Traits and performance measures can be examined
at the level of individual organisms or groups of
species (i.e. functional groups). For example, traits
associated with maximization of reproductive
success can be combined to classify organisms
according to functional groups based on life history
strategies (i.e. syndromes defined by consistent
patterns of trait intercorrelations).
• Functional traits influence environmental tolerances
and habitat requirements, and dictate both species
responses to a changing environment and their
effects on ecosystem services .
• .
• If species sharing similar traits display similar
responses to environmental changes, a functional
approach may improve our ability to quantify and
predict impacts of dams on fish assemblages and
fisheries across biogeographic regions.
• Focusing specifically on large tropical rivers, we
explore: (i) the potential of using functional traits
to understand the impacts of hydrologic alteration
on fishes and fisheries, (ii) patterns of functional
responses to river impoundment (e.g. identifying
functional traits of vulnerable or tolerant species),
and (iii) some consequences of functional diversity
changes for social-ecological systems

23. Impacts of dams on fisheries in India
• Dams have had negative impact on river fisheries in various systems throughout the region. Sharp declines in
catches of Hilsa ilisha were noticed as a result of dams, barrages, weirs and anaicuts on the Hooghly, Godavari,
Krishna and Cauvery rivers, and that mahseer Tor putitora and T. tor no longer are found above Nangal and
Talwara dams. Fish ways constructed in conjunction with dams are used as fish traps by local fishers.
• In addition to impacts on hilsa and mahseer stocks and their associated fisheries, formation of reservoirs in
India has had negative impact on snow trout (Schizothorax), and rohu (Labeo) in Himalayan streams, and
catadromous eels and freshwater prawns in all major river systems. One of the earliest known impacts to river
fisheries in India occurred as a result of construction of Mettur Dam (1935) on the Cauvery River, which
formed Stanley Reservoir and completely stopped runs of the Indian shad Tenualosa ilisha. Within the reservoir
itself, water level changes, recruitment failures and predation resulted in reduced stocks of Indian major carps.
• Reservoirs in Punjab region have resulted in good fisheries, with more than 1,800 t/year landed annually at
Bhakra Dam and Pong Dam, collectively. In the reservoirs formed by these dams high yield fisheries have
evolved, primarily through development of stocks of exotic fishes (eg, the fishery for the exotic silver
carp, Hypophthalmichthys molitrix contributes more than 30% to the catch from Gobindsagar Lake).
• However, river fisheries have been negatively impacted, particularly with regard to migratory fishes.
Construction of barrages at Ropar, Harike and Ferozepur has restricted migration of Indian major carps, in spite
of fishways. During most of the year, little water is released into the river below the dams from the reservoirs,
and fish are concentrated in pools where they are more easily captured by fishers. Fishways designed to
promote fish passage past dams are used by fishers to capture fish. Dams in India’s Punjab region have reduced
flooding, but in so doing they have also negatively impacted production of Indian major carps, resulting in
reduced total fish production for the region.
• Persons linked to river fisheries through culture, tradition and economics incorporate these fisheries as
dominant components of their human identities. Reorientation of their values and activities after impacts to or
loss of the foundation for their identities can generate considerable socio-economic stress to these people,
their communities and their cultures.

24. Dams negative impacts on fishes
• Loss of natural habitat is one of major negative impact of dams so during a
life fish/aquatic species face many problems related spawning for example
on the Indus river, the construction of the Gulam Mahommed Dam has
deprived the migratory Hillsa ilisha of 60% of their previous spawning areas
and on the Columbia river and its main tributary the Snake river, most
spawning habitat were flooded, due to the construction of dams creating an
uninterrupted series of impoundments
• The most proximate impact of sediment starvation is the enhancement of
erosion downstream of dams from out flow causing channel incision that
can degrade within channel habitats for macro invertebrates and fish
(Kondolf, 1997).
• Sounding a warning that over five billion people across the globe may run
into water shortage, a United Nations report has pointed out that dams in
India have done more harm than good to the cause of water security.
• A number of studies have documented that the upstream migration may be
delayed for many weeks at man-made obstacles such as power station
outlets, residual flow stretches, dams, weirs and fishways (Thorstad et al.,
2008)

25. References
• https://indiawris.gov.in/wiki/dok
u.php?id=dams_in_indus_basin
• https://www.thethirdpole.net/en
/nature/species-vanish-as-indus-
loses-water/
• https://www.researchgate.net/p
ublication/342902155_Fish_Dive
rsity_of_Mahanadi_River_Odish
a_Part_Threats_and_Conservati
on_Measures
• https://www.scribd.com/docum
ent/627217139/A-CHECKLIST-
OF-FISHES-OF-MAHANADI-
RIVER-INDIA-1
• https://www.thepharmajournal.c
om/archives/2021/vol10issue7S/
PartF/S-10-7-25-546.pdf
• https://en.wikipedia.org/wiki/T
apti_River
• https://en.wikipedia.org/wiki/N
armada_River
• https://www.researchgate.net/
publication/342900834_Finfish
_Diversity_of_River_Narmada_
and_Its_Tributaries
• https://www.sciencedirect.com
/science/article/abs/pii/S18773
43518301003
• https://scienceandculture-
isna.org/uploads/latestIssue/04
_Basanta_Kumar_Das_and_Arc
hisman_Ray_Art-3.pdf
• https://news.mongabay.com/20
20/02/past-and-future-tropical-
dams-devastating-to-fish-the-
world-over-study/