Document: 1. Introduction
Section: 4. Discussions > 4.3. Risk
Type: table
Table: Table 2 Details of Lakes Having PFV Higher Than $5 \times 10^6 \, \mathrm{m}^3$

| Lake ID | ID (this study) | Lake details      |                  |                 |                  |               |                    |                    | Hazard                   |                   |                            |           | Lake ID (this study) | Hazard   |                             | Downstream impact |         |                    | Ranking        |                           |              | PFV (106 m3)  |
|---------|--------------------|-------------------|------------------|-----------------|------------------|---------------|--------------------|--------------------|--------------------------|-------------------|----------------------------|-----------|----------------------|----------|-----------------------------|-------------------|---------|--------------------|----------------|---------------------------|--------------|---------------|
|         |                    | Common name    | Longitude (°) | Latitude (°) | Elevation (m) | Aspect (°) | Area (km2) 1993 | Area (km2) 2018 | Significant expansion | Lakes upstream | Presence of ice core | Avalanche |                      | Rockfall | Steep moraine (slope > 10°) | Buildings         | Bridges | Hydropower systems | Hazard ranking | Downstream impact ranking | Risk ranking |               |
|         | 216                | Gurudongmar       | 88.710           | 28.026          | 5,130            | 350           | 1.149              | 1.12               | 0                        | 1                 | 0                          | 0         | 216                  | 0        | 1                           | 300               | 5       | 0                  | 1              | 2                         | 1            | 49.89 ± 21.95 |
|         | 160                | Tso Lhamo         | 88.713           | 28.005          | 5,231            | 340           | 1.155              | 1.247              | 1                        | 0                 | 1                          | 1         | 160                  | 1        | 1                           | 300               | 5       | 0                  | 3              | 2                         | 3            | 49.89 ± 21.95 |
|         | 205                | Tso Lhamo         | 88.756           | 28.012          | 5,072            | 340           | 1.111              | 1.058              | 0                        | 0                 | 0                          | 0         | 205                  | 0        | 1                           | 238               | 14      | 0                  | 1              | 2                         | 1            | 39.54 ± 17.4  |
|         | 206                |                   | 88.698           | 28.007          | 5,228            | 20            | 0.906              | 1.018              | 1                        | 0                 | 1                          | 0         | 206                  | 1        | 1                           | 283               | 16      | 0                  | 2              | 2                         | 2            | 37.46 ± 16.48 |
|         | 47                 | J R B Lake        | 75.179           | 34.666          | 4,252            | 35            | 0.746              | 0.757              | 0                        | 0                 | 0                          | 0         | 47                   | 0        | 1                           | 78                | 6       | 0                  | 1              | 1                         | 1            | 24.64 ± 10.84 |
|         | 202                | Khangchung Tso | 88.816           | 27.990          | 5,288            | 300           | 1.647              | 1.775              | 0                        | 0                 | 1                          | 1         | 202                  | 1        | 1                           | 150               | 3       | 0                  | 3              | 2                         | 3            | 19.93 ± 8.77  |
|         | 279                | Tso               | 92.033           | 27.519          | 4,272            | 10            | 0.617              | 0.588              | 0                        | 0                 | 0                          | 0         | 279                  | 0        | 1                           | 154               | 13      | 0                  | 1              | 2                         | 1            | 17.26 ± 7.59  |
|         | 161                | Shakho Cho        | 88.616           | 27.975          | 5,010            | 30            | 0.574              | 0.576              | 0                        | 0                 | 0                          | 1         | 161                  | 1        | 1                           | 350               | 8       | 0                  | 3              | 2                         | 3            | 16.78 ± 7.38  |
|         | 132                | Chandra Tal       | 77.615           | 32.483          | 4,262            | 300           | 0.53               | 0.49               | 0                        | 0                 | 0                          | 0         | 132                  | 1        | 1                           | 48                | 2       | 0                  | 1              | 1                         | 1            | 13.34 ± 5.87  |
|         | 207                |                   | 88.761           | 27.895          | 5,232            | 280           | 0.466              | 0.476              | 0                        | 1                 | 1                          | 1         | 207                  | 0        | 1                           | 172               | 8       | 0                  | 3              | 2                         | 3            | 12.78 ± 5.62  |
|         | 299                |                   | 93.820           | 28.616          | 3,600            | 315           | 0.467              | 0.468              | 0                        | 0                 | 0                          | 0         | 299                  | 0        | 1                           | 5                 | 5       | 0                  | 1              | 1                         | 1            | 12.49 ± 5.49  |
|         | 71                 | Shaushar          | 75.236           | 34.991          | 4,142            | 200           | 1.296              | 1.342              | 0                        | 0                 | 1                          | 0         | 71                   | 0        | 1                           | 0                 | 0       | 0                  | 2              | 0                         | 1            | 9.02 ± 3.97   |
|         | 324                | South Lhonak      | 88.195           | 27.912          | 5,210            | 75            | 0.59               | 1.44               | 1                        | 1                 | 1                          | 0         | 324                  | 0        | 1                           | 40                | 3       | 0                  | 2              | 1                         | 1            | 8.92 ± 3.92   |
|         | 313                |                   | 93.578           | 28.576          | 3,879            | 30            | 0.396              | 0.363              | 0                        | 1                 | 0                          | 0         | 313                  | 0        | 1                           | 16                | 4       | 0                  | 1              | 1                         | 1            | 8.74 ± 3.85   |
|         | 307                |                   | 93.437           | 28.305          | 3,944            | 355           | 0.196              | 0.351              | 1                        | 0                 | 0                          | 0         | 307                  | 0        | 1                           | 10                | 3       | 0                  | 1              | 1                         | 1            | 8.31 ± 3.66   |
|         | 24                 | Lolgul Gali       | 74.892           | 34.444          | 3,864            | 350           | 0.345              | 0.35               | 0                        | 0                 | 1                          | 0         | 24                   | 0        | 1                           | 1,400             | 3       | 0                  | 2              | 2                         | 2            | 8.3 ± 3.65    |
|         | 159                |                   | 88.546           | 27.993          | 5,178            | 75            | 0.562              | 0.595              | 0                        | 0                 | 1                          | 1         | 159                  | 1        | 1                           | 350               | 8       | 0                  | 3              | 2                         | 3            | 8.17 ± 3.6    |
|         | 236                |                   | 88.512           | 27.672          | 4,525            | 70            | 0.319              | 0.333              | 0                        | 0                 | 0                          | 0         | 236                  | 0        | 1                           | 12                | 5       | 1                  | 1              | 1                         | 1            | 7.71 ± 3.39   |
|         | 48                 |                   | 75.137           | 34.697          | 4,121            | 350           | 0.633              | 0.549              | 0                        | 0                 | 1                          | 0         | 48                   | 0        | 1                           | 78                | 6       | 0                  | 2              | 1                         | 1            | 7.32 ± 3.22   |
|         | 214                |                   | 88.639           | 28.002          | 5,423            | 350           | 0.319              | 0.317              | 0                        | 0                 | 1                          | 1         | 214                  | 1        | 1                           | 395               | 8       | 0                  | 3              | 2                         | 3            | 7.21 ± 3.17   |
|         | 283                |                   | 91.875           | 27.673          | 4,220            | 20            | 0.336              | 0.307              | 0                        | 0                 | 0                          | 0         | 283                  | 0        | 1                           | 40                | 11      | 0                  | 1              | 1                         | 1            | 6.89 ± 3.03   |
|         | 133                | Geepang Gath      | 77.220           | 32.525          | 4,088            | 160           | 0.42               | 0.941              | 1                        | 0                 | 0                          | 0         | 133                  | 1        | 1                           | 3                 | 2       | 1                  | 1              | 1                         | 1            | 6.76 ± 2.97   |
|         | 156                |                   | 78.987           | 30.745          | 4,749            | 330           | 0.229              | 0.292              | 1                        | 0                 | 0                          | 0         | 156                  | 0        | 1                           | 82                | 0       | 1                  | 1              | 1                         | 1            | 6.42 ± 2.83   |
|         | 282                |                   | 91.870           | 27.746          | 4,371            | 20            | 0.459              | 0.439              | 0                        | 0                 | 0                          | 0         | 282                  | 0        | 1                           | 165               | 10      | 0                  | 1              | 2                         | 1            | 6.33 ± 2.79   |
|         | 131                | Lam Dal           | 76.332           | 32.336          | 3,962            | 320           | 0.274              | 0.272              | 0                        | 0                 | 1                          | 0         | 131                  | 0        | 1                           | 9                 | 4       | 0                  | 2              | 1                         | 1            | 5.82 ± 2.56   |
|         | 196                | Tsomgo            | 88.763           | 27.375          | 3,753            | 270           | 0.231              | 0.269              | 0                        | 0                 | 0                          | 0         | 196                  | 0        | 1                           | 275               | 9       | 2                  | 1              | 3                         | 2            | 5.45 ± 2.4    |
|         | 130                |                   | 78.167           | 31.661          | 4,278            | 20            | 0.122              | 0.257              | 1                        | 0                 | 0                          | 0         | 130                  | 1        | 1                           | 6                 | 0       | 1                  | 1              | 1                         | 1            | 5.36 ± 2.36   |
|         | 310                |                   | 93.726           | 28.594          | 4,218            | 260           | 0.252              | 0.25               | 0                        | 0                 | 0                          | 0         | 310                  | 0        | 1                           | 16                | 4       | 0                  | 1              | 1                         | 1            | 5.14 ± 2.26   |
|         | 311                |                   | 93.712           | 28.585          | 3,894            | 20            | 0.135              | 0.144              | 0                        | 1                 | 0                          | 0         | 311                  | 0        | 1                           | 16                | 4       | 0                  | 1              | 1                         | 1            | 5.14 ± 2.26   |
|         | 209                |                   | 88.561           | 28.014          | 5,070            | 110           | 0.262              | 0.27               | 0                        | 0                 | 0                          | 1         | 209                  | 1        | 1                           | 350               | 8       | 0                  | 3              | 2                         | 3            | 5.06 ± 2.23   |
|         | 210                |                   | 88.572           | 28.007          | 4,997            | 130           | 0.275              | 0.268              | 0                        | 1                 | 0                          | 0         | 210                  | 1        | 1                           | 350               | 8       | 0                  | 1              | 2                         | 1            | 5.06 ± 2.23   |
|         | 81                 |                   | 74.961           | 35.082          | 4,320            | 0             | 0.251              | 0.246              | 0                        | 1                 | 0                          | 0         | 81                   | 0        | 1                           | 135               | 11      | 0                  | 1              | 2                         | 1            | 5.03 ± 2.21   |

Lake ID
ID (this study)
Lake details
Hazard
Lake ID (this study)
Hazard
Downstream impact
Ranking
PFV (106 m3)


Document: 1. Introduction
Section: 4. Discussions > 4.3. Risk
Type: text

Note. Ranking value (0) represents low, (1) represents moderate, (2) represents high, and (3) represents very high. For hazard, (1) represents yes, and (0) represents no.

1944793, 2020, 4, Downloaded from https://gupubxo.ninelbhray.wiley.com/doi/10.1029/2019WR02553 by Indian Institute Of Technology Bombay, Wiley Online Library on [08/08/2025]. See the Terms and Conditions (https://onlinelbtrary.wiley.com/terms-und-conditions) on Wiley Online Library on (19/08/2025].

DUBEY AND GOYAL 16 of 21

Note: Ranking value (0) represents low, (1) represents moderate, (2) represents high, and (3) represents very high. For hazard, (1) represents yes, and (0) represents no.

1944793, 2020, 4, Downloaded from https://gupubxo.ninelbhray.wiley.com/doi/10.1029/2019WR02553 by Indian Institute Of Technology Bombay, Wiley Online Library on [08/08/2025]. See the Terms and Conditions (https://onlinelbtrary.wiley.com/terms-und-conditions) on Wiley Online Library on (19/08/2025].

DUBEY AND GOYAL 17 of 21

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wiley.com/doi/10.1029/2019WR026533 by Indian Institute Of Technology Bombay, Wiley Online Library on [08/08/2025]. See the Terms

are governed by the applicable Creative Commons Licens

GLOF from these lakes would significantly improve the hazard and downstream risk assessment and aid the stakeholders in taking decisions related to risk mitigation measures.

data/('Water Resources Research - 2020 - Dubey - Glacial Lake Outburst Flood Hazard  Downstream Impact  and Risk Over the Indian', '.pdf')_extraction.md


Document: 1. Introduction
Section: 4. Discussions > 4.4. Implications for Stakeholders
Type: text

Accurate identification of potentially dangerous glacial lake is challenging, but yet a crucial task and is vital to maintain the trustworthiness of the decision-makers and local communities. Generally, the regional studies assess different parameters to identify potential hazard associated with glacial lakes, and therefore, the obtained results depict very different results. Therefore, we recommend the stakeholders to base the decision criteria on the analysis based on new and more comprehensive data, more sophisticated analysis, enhanced understanding of system, and robust model simulations with wider consideration of uncertainties. The important characteristics to prioritize the glacial lake studies should be (1) credibility of the evidence that the applied model relies upon; (2) standardized application of methodology; (3) inclusion of most frequent GLOF triggers; and (4) the level of details in the estimated probable impact.

The primary objective of policy-research linkage should be to convey advanced scientific data and technology to planning and mitigation and ultimately reduce the projected risk. One crucial aspect of these hazard assessments is the consideration of worst-case scenarios, something that is not very likely and this must be appropriately communicated to the decision-makers. Second, there should be formal communication channels between policy-makers and research scientists to enable precise knowledge transfer and lastly, although the associated risk with the glacial hazards is very high, yet is mostly indeterminate, and the present tendency of grossly overstating the results in terms of both hazard and potential catastrophe needs to be realized and strictly discouraged.

4. Discussions
4.4. Implications for Stakeholders


Document: 1. Introduction
Section: 5. Conclusions
Type: text

The present study implemented a comprehensive evaluation of hazard, downstream impact, and associated risk for 329 glacial lakes with size greater than 0.05 km2 in the Indian Himalayas. The implemented methodology assesses the most frequent triggers based on the detailed literature review which includes avalanche, rockfall, stability of the damming moraine, expansion rate, and presence of ice cores. The results indicated that glacial lakes expanded by 15.84% between 1993 and 2018, where 64 lakes significantly expanded and 6 lakes significantly drained; 36 lakes are susceptible to an avalanche where most of the hit is expected along the minor axis. Application of stochastic flood model reveals that 67 glacial lakes contain at least one hydropower system along their flow path. The risk assessment indicates that there are 23 very high risk lakes and 50 high-risk lakes in the Indian Himalayas. The main objective of the study was to implement an objective methodology that was least subjective as possible. Conversely, with the present state of knowledge regarding triggering mechanisms of GLOF and available remotely sensed satellite data, there is a certain level of subjectiveness that is inherently inescapable in these first pass GLOF assessments.

We recommend the use of downstream impact along with potential flood volume for both dynamic and self-destructive failures to rank glacial lakes as with sizeable flood volume, proximities of the area of settlement and socioeconomic consequence are equally essential to recognize a lake as potentially dangerous. Some of the notable lakes with very high PFV include Gurudongmar Lake, Tso Lhamo Lake, and J R B Lake, whereas some of the lakes with high PFV and very high risk include Khangchung Tso and Shakho Cho. The use of hydrodynamic model, along with field-based assessments, is strongly suggested before implementing any risk mitigation measures. Additionally, as higher temporal resolution DEMs become available, the hazard assessment should be repeated as it will enable DEM differencing which will significantly improve the identification of ice cores and the modeling of dynamic failures.


Document: GL Atlas Indus 12Nov2020 Final
Section: FOREWORD
Type: text

Indian Himalayas contain the largest number of glaciers other than Polar Regions of the world. These glaciers along with seasonal snow cover are the major source of fresh water and three major river systems originating from Himalayas are nourished by their melt waters, thereby supporting the livelihood of millions of people. Glacial lakes are common features around the margins of glaciers, originating from retreating or thinning processes of glacier. The area and volume of glaciers have been changing rapidly since past few decades due to natural and anthropological effects, with most of them losing mass as they thinned and their termini retreated, resulting in the formation of new glacial lakes. These glacial lakes may at times release large quantities of glacier melt water from associated moraine or ice-dam due to breach/failure, resulting in catastrophic flood in the downstream area, with significant socio-economic impacts. It is essential to have knowledge on location of glacial lakes, their susceptibility, and the probable consequences of GLOF risk. Earth Observation satellite data is useful in mapping and monitoring of glacial lakes, which by traditional means is nearly impossible task due to highly rugged and inaccessible terrain.

The present atlas is brought out as part of an activity on “Glacial Lake Outburst Flood (GLOF) Risk Assessment of Glacial Lakes in the Himalayan Region of Indian River Basins”, taken up under the National Hydrology Project, funded by the Department of Water Resources, River Development and Ganga Rejuvenation (DoWR, RD&GR), Ministry of Jal Shakti, Government of India. This atlas is first of its kind depicting spatial distribution of glacial lakes of size greater than 0.25 ha in the Indus River basin using high resolution satellite data from Resourcesat-2 LISS-IV MX. Glacial lakes are inventoried for the Indus River basin, within both India and transboundary region. The details of glacial lakes are systematically documented at basin, subbasin, administrative, and transboundary region level, including lake type, area, and elevation distribution.

The atlas forms as an authentic and recent reference data, and is useful in monitoring glacial lake dynamics, GLOF risk assessment, and long-term climate change impact analysis.

I commend the study team for taking up this initiative to bring out an exclusive “Glacial Lake Atlas of Indus River Basin”. I sincerely hope that this exhaustive atlas will be of immense value to Central/State water resources, environmental and disaster organisations, and as well as to academicians and researchers.

October 26, 2020

(Santanu Chowdhury)

भारतीय अन्तरिक्ष अनुसंधान संगठन Indian Space Research Organisation


Document: GL Atlas Indus 12Nov2020 Final
Section: GLACIAL LAKE ATLAS OF INDUS RIVER BASIN > SUMMARY
Type: text

National Remote Sensing Centre (NRSC), Indian Space Research Organisation (ISRO), Hyderabad as one of the Implementing Agency under the National Hydrology Project (NHP), is carrying out hydrological studies using satellite data and geospatial techniques. As part of this, detailed glacial lake inventory, prioritization for Glacial Lake Outburst Flood (GLOF) risk, and simulation of GLOF for selected lakes are taken up for entire catchment of Indian Himalayan Rivers. Under this activity, an updated inventory of glacial lakes has been prepared for the Indus River basin using high resolution satellite data. The present glacial lake atlas is based on the inventoried glacial lakes in part of Indus River basin from its origin to foothills of Himalayas covering a catchment area of 3,42,841 Km2.

The study portion of Indus River basin covers part of India and transboundary region. Indus River basin has been divided into nine subbasins on the basis of confluence of major rivers contributing into the system viz., Satluj, Beas, Ravi, Chenab, Jhelum, and Zaskar joining the main river on the left, whereas rivers like Sengee Tsangpo, Shyok, and Gilgit joining on the right. Elevation in the river basin varies from the minimum 153 m to the maximum 8,557 m amsl. In India, Indus River basin extends in two states and two union territories (UT’s) viz., Himachal Pradesh and Uttarakhand, and Jammu & Kashmir and Ladakh, respectively.

In the present study, glacial lakes with water spread area greater than 0.25 ha have been mapped using Resourcesat-2 (RS-2) Linear Imaging Self Scanning Sensor-IV (LISS-IV) satellite data using visual interpretation techniques. Based on its process of lake formation, location, and type of damming material, glacial lakes are identified in ten different types, majorly grouped into four categories viz., Moraine-dammed, Ice-dammed, Glacier Erosion, and Other glacial lakes.

A total of 5,335 glacial lakes have been mapped in the Indus River basin using a total of 157 high resolution multispectral RS-2 LISS-IV images, with a total lake water spread area of 17,395 ha. Each glacial lake has been given a 12 alpha-numeric unique glacial lake ID, along with several attributes that include hydrological, geometrical, geographical, and topographical characteristics. About 4,633 (86.84%) lakes are with < 5 ha lake area contributing to 34.04% of total lake area. The remaining lakes with > 5 ha in size are 702 (13.16%) contributing to 65.96% of total lake area in the basin. There are only 34 glacial lakes in the Indus River basin having an area of greater than 50 ha. Other Glacial Erosion lake type are found to be the maximum with 2,516 (47.16%) occupying a total lake extent of 8,247.44 ha (47.41%) in the basin. More than half (i.e. 52.43%) of the lakes are situated in the high altitude range of 4,001 - 5,000 m amsl and dominated by Other Glacial Erosion lake type i.e., 58.17%.

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN
SUMMARY

Beas Chenab Gilgit Jhelum Ravi Satluj Shyok


Document: GL Atlas Indus 12Nov2020 Final
Section: GLACIAL LAKE ATLAS OF INDUS RIVER BASIN > SUMMARY
Type: text

lake area in the basin . There are only 34 glacial lakes in the Indus River basin having an area of greater than 50 ha . Other Glacial Erosion lake type are found to be the maximum with 2 , 516 ( 47 . 16 % ) occupying a total lake extent of 8 , 247 . 44 ha ( 47 . 41 % ) in the basin . More than half ( i . e . 52 . 43 % ) of the lakes are situated in the high altitude range of 4 , 001 - 5 , 000 m amsl and dominated by Other Glacial Erosion lake type i . e . , 58 . 17 % .

Glacial lakes are predominantly distributed in the Gilgit subbasin (18.95%) followed by Indus Upper subbasin (18.78%) with a total lake extent of 3,380.27 ha and 3,467.01 ha at 19.43% and 19.93% respectively in the entire basin. In terms of lake extent, Indus Upper subbasin has large lake area. Minimum number of glacial lakes are present in Ravi subbasin (1.14%) and then in Beas subbasin (1.80%). Other Glacial Erosion lakes, which are dominant lake type in Indus River basin are uniformly distributed in all subbasins, and found maximum in count in all subbasins (predominantly in Gilgit subbasin), except Shyok subbasin which has Supra-glacial lakes in majority. However, Glacier Ice-dammed and Glacier Trough Valley Erosion lakes are only located in Shyok and Gilgit subbasin respectively. Shyok subbasin also consists of higher number of Lateral Moraine dammed lake with ice in the entire Indus River basin.

A total of 4,280 (i.e. 80.23%) glacial lakes lies within Indian region covering 79.26% of the total lake area, whereas remaining 19.77% of lakes are located in transboundary region with a 20.74% of the total lake area.

In Indian region, majority of glacial lakes are of Other Glacial Erosion type (48.11%), followed by Supra-glacial lakes (17.78%) and Other Moraine Dammed lakes (14.77%). Ladakh (UT) shares 75.21% of lake count, followed by 12.76% and 11.99% in Jammu & Kashmir (UT) and Himachal Pradesh respectively, with a total lake area of 72.28%, 20.90%, and 6.73% respectively. Whereas, remaining 0.04% of glacial lakes are found in Uttarakhand state, covering only 0.09% of lake area. Majority of lakes in Ladakh (UT) and Jammu & Kashmir (UT) are of lake area ranging in 1 - 5 ha category but lying in high (4,001 - 5,000 m) and medium altitude range (3,001 - 4,000 m) respectively. Whereas, 95.52% of lakes in Himachal Pradesh are less than 5 ha situated above 4,000 m amsl. Lakes in Uttarakhand are only situated in very high altitude range i.e. above 5,000 m amsl under two area ranges i.e. 0.25 - 5 ha and 10 - 50 ha.


Document: GL Atlas Indus 12Nov2020 Final
Section: GLACIAL LAKE ATLAS OF INDUS RIVER BASIN > SUMMARY
Type: text

of lakes in Ladakh ( UT ) and Jammu & Kashmir ( UT ) are of lake area ranging in 1 - 5 ha category but lying in high ( 4 , 001 - 5 , 000 m ) and medium altitude range ( 3 , 001 - 4 , 000 m ) respectively . Whereas , 95 . 52 % of lakes in Himachal Pradesh are less than 5 ha situated above 4 , 000 m amsl . Lakes in Uttarakhand are only situated in very high altitude range i . e . above 5 , 000 m amsl under two area ranges i . e . 0 . 25 - 5 ha and 10 - 50 ha .

In this atlas, map sheets (plates) are prepared on the basis of the Survey of India (SOI) toposheet index (1:250,000 scale) which are 56 in number covering the entire Indus River basin. Out of 56 plates, only 46 plates have glacial lakes and corresponding plates are incorporated in atlas. The map sheets are arranged in such a way that glacial lake map is on the right page and its corresponding satellite image is on the left page. At the end of the atlas, an annexure is provided containing list of all glacial lakes inventoried in the Indus River basin with their unique glacial lake ID, latitude, longitude, subbasin, glacial lake type, area (ha), and elevation (m). Glacial Lake ID number of 12 alpha-numeric character has 3 characters bold with dark red colour depicting the corresponding toposheet number of the SOI of 1:250,000 scale.

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN


Document: GL Atlas Indus 12Nov2020 Final
Section: 1. INTRODUCTION > 1.1 About Project
Type: text

The National Hydrology Project (NHP) sponsored by Department of Water Resources, River Development and Ganga Rejuvenation (DoWR, RD&GR), Ministry of Jal Shakti, Government of India (GOI) with financial aid from the World Bank. The objective of the project is to improve the extent and accessibility of water resources information and strengthen institutional capacity to enable improved water resources planning and management across India. The mission is to establish an effective and sound hydrologic database and Hydrological Information System (HIS), together with the development of consistent and scientifically based tools and design aids, to assist in the effective water resources planning and management of the implementing agencies.

NHP is intended for setting up of a system for timely and reliable water resources data acquisition, storage, collation and management. It will also provide tools/systems for informed decision making through Decision Support System (DSS) for water resources assessment, flood management, reservoir operations, drought management, etc. NHP also seeks to build capacity of the State and Central sector organisations in water resources management through the use of Information Systems and adoption of State-of-the-art technologies like Remote Sensing. NHP will improve and expand hydrology data and information systems, strengthen water resources operation and planning systems, and enhance institutional capacity for water resources management. NHP will contribute to the GOI Digital India initiative by integrating water resources information across State and Central agencies.

National Remote Sensing Centre (NRSC), as one of the Implementing Agency under NHP, is engaged with generation of geo-spatial products & services pertaining to water resources sector, generation of high resolution Digital Elevation Models (DEM), development of flood early warning systems, decision support system development for irrigation water management, modelling & dissemination of hydrological products to support water resources management and capacity building to NHP stakeholders. The satellite data based geo-spatial products & services, mainly encompassing the following:

- Satellite Data/Geo-Spatial Data Hosting & Services through Bhuvan Web Portal
- Water Resources Information Products & Services (Satellite/Model derived – Bhuvan/India- Water Resources Information System (India-WRIS)/National Water Informatics Centre (NWIC))
- Customized Applications Development (Flood Forecasting, Irrigation Water Management)
- Hydro-conditioned Digital Elevation Model (Satellite & Aerial)
- Capacity Building (Customized Training & Hand Holding)

As part of various NHP technical studies carried out, NRSC has taken up “Glacial Lake Outburst Flood (GLOF) Risk Assessment of Glacial Lakes in the Himalayan Region of Indian River Basins”. In this activity, it was proposed to prepare an updated inventory of glacial lakes, prioritization and selection of critical glacial lakes based on certain characteristics (such as glacial lake, glacier, topography and others), GLOF modelling and flood inundation simulation for selected few lakes using high resolution Digital Elevation Model (DEM) for downstream of the lakes along their river reach, and to assess GLOF risk.

As a result of initial outcome of this activity, an updated inventory of glacial lakes in Indus River basin was generated using multispectral (MX) high resolution satellite data of Resourcesat-2 Linear Imaging Self Scanning

***

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN

Sensor-IV (LISS-IV) for mapping lakes with size > 0.25 ha. The geo-spatial database of glacial lakes has been used to prepare atlas of “Glacial Lake Atlas of Indus River Basin”.


Document: GL Atlas Indus 12Nov2020 Final
Section: 1. INTRODUCTION > 1.2 Glacial Lakes
Type: text

Indian Himalayan Region (IHR) contains the world’s largest number of glaciers and snow outside the Polar Regions and are aptly called third pole of the world. Many studies undertaken globally showed that glaciers around the world have been retreating since the industrial revolution, which began around eighteenth century. As the glaciers are thinning and retreating, resulting in associated glacier melt water lakes are expanding in size and new lakes continue to be formed. The lakes receiving melt water from glaciers are generally known as glacial lakes. A glacial lake is defined as water mass existing in a sufficient amount and extending with a free surface in, under, beside, and/or in front of a glacier and originating from glacier activities and/or retreating processes of a glacier. As glaciers retreat, the formation of glacial lakes takes place behind moraine or ice ‘dam’. These damming materials are generally weak and can breach suddenly due to various triggering factors, leading to catastrophic floods. Such outburst floods are known as GLOF.

GLOFs are characterized by extreme peak discharges, with an exceptional erosion/transport potential; therefore, they can turn into flow-type movements (Emmer, 2017). Failure of such lake happens due to many factors which include erosion process, increase in water pressure, merging of an avalanche/rock into lake, nature of the damming materials etc., and this may lead to a GLOF event which could be highly disastrous in nature and create long-term degradation in the valleys, both physically and socio-economically (Mool et al., 2001b). Accordingly, Emmer et al., (2016) showed an annual nonlinear increase in the number of scientific publications focusing on GLOFs recently. Hence, monitoring of glacier associated lakes is very useful in the IHR to identify critical glacial lakes, for which a detailed inventory of glacial lakes and its type is required. According to their position relative to the glacier and damming mechanism, these glacial lakes can be classified into several types (Panda et al., 2014).

Inventorying glacial lakes located in these remote mountain areas with rugged terrain and inclement weather by traditional means is very tedious and difficult, hence Remote Sensing (RS) data plays a greater role in generating information on glacial lakes (Kulkarni, 1991; Berither et al., 2007; Wagnon et al., 2007; Raj, 2010; Cogley et al., 2011; Pratap et al., 2016; Gupta et al., 2019; Guru et al., 2019). Satellites with high spatial, spectral and temporal resolution sensors are useful in deriving lake information with better accuracy and repeatedly.


Document: GL Atlas Indus 12Nov2020 Final
Section: 1. INTRODUCTION > 1.3 Previous Studies
Type: text

Several studies have been taken up in the past to assess the glacial lake distribution in the Hindu Kush Himalayas (HKH), covering parts of eight countries viz., Afghanistan, Bangladesh, Bhutan, China, India, Myanmar, Nepal, and Pakistan, and lies within five river basins of Amu Darya, Indus, Ganga, Brahmaputra, and Irrawaddy (Komori, 2007; Gardelle et al., 2011; Wang et al., 2011; Wang et al., 2012; Nie et al., 2013; Raj et al., 2013; Wang et al., 2013; Worni et al., 2013; Che et al., 2014; Bambari et al., 2015; Zhang et al., 2015; Nie et al., 2017; Rounce et al., 2017; Nagai et al., 2017; Gupta et al., 2019; Guru et al., 2019; Shugar et al., 2020). But only few glacial lake inventories are available in public domain, amongst which the first inventory was prepared by the International Centre for Integrated Mountain Development (ICIMOD), Nepal, for the entire HKH region (covering the entire IHR within it), using satellite data of the Land Observation Satellite (Landsat) Thematic Mapper (TM) of the United States Geological Survey (USGS) and the Indian Remote Sensing satellite (IRS-1D) Linear Imaging and

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN

Self-scanning Sensor-III (LISS-III) during 1999-2005, along with topographic maps published between the 1950s and 1982 (Mool et al., 2001a; Mool et al., 2001b; Mool et al., 2003; Bhagat et al., 2004; Roohi et al., 2005; Sah et al., 2005; Wu et al., 2005, Ives et al., 2010). This inventory has been revised in 2018 using Landsat TM and Enhanced Thematic Mapper Plus (ETM+) data of years 2004-07 ± 3 (Maharjan et al., 2018). Both glacial lake inventories prepared by the ICIMOD, have mapped lakes with size > 0.3 ha.

Second inventory of glacial lakes and water bodies in the IHR (within India only) was carried out by the NRSC, Hyderabad in collaboration with the Central Water Commission (CWC), New Delhi. Glacial lakes and water bodies located in all three major basins of Indus, Ganga, and Brahmaputra, of size > 10 ha were mapped using Indian Remote Sensing (IRS) Advanced Wide Field Sensor (AWiFS) data for the year 2009 (NRSC, 2011). Subsequently, monthly monitoring of these lakes (> 50 ha) was carried out using satellite data for the months of June to October during the years 2011 to 2015.

Third latest glacial lake inventory is prepared by the Space Application Centre (SAC), Ahmedabad i.e. “National Wetland Atlas: High Altitude Lakes of India”, using IRS-P6 LISS-III, comprising high altitude lake information of the IHR, within Indian administrative region only (Panigrahy et al., 2012). In this atlas, wetlands of size > 2.25 ha were mapped as a polygons and less than that were mapped as a points, using satellite data for the period of 2006-08.


Document: GL Atlas Indus 12Nov2020 Final
Section: 1. INTRODUCTION > 1.4 Highlights of the Atlas
Type: text

**The highlights of the present atlas:**
* The present atlas is first of its kind depicting spatial distribution of glacial lakes of size greater than 0.25 ha in Indus river basin mapped using high resolution satellite data
* The atlas provides the details of all the glacial lakes in entire catchment of Indus River basin, both within Indian and transboundary region
* The atlas contains details of area range-wise glacial lakes along with 10 categories of types. Further, the atlas present the distribution of glacial lakes in terms of area vs. type, elevation, area vs. elevation, and type vs. elevation, at basin, sub-basin, administrative, and transboundary regions
* The atlas also provides comprehensive list of all glacial lakes with unique ID considering hydrological, geometrical, geographical, topographical attribute information

**The expected utility of the atlas:**
* The atlas provides a comprehensive and systematic glacial lake database for Indus River basin with size > 0.25 ha
* In the context of climate change impact analysis, the atlas can be used as reference data for carrying out change analysis, both with respect to historical and future time periods
* The atlas also provides authentic database for regular or periodic monitoring changes in spatial extent (expansion/shrinkage), and formation of new lakes
* The atlas can also be used in conjunction with glacier information for its retreat and climate impact studies
* The information on glacial lakes like their type, hydrological, topographical, and associated glaciers are useful in identifying the critical glacial lakes and consequent GLOF risk
* Central and State Disaster Management Authorities can make use of the atlas for disaster mitigation planning and related programs

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN

1. INTRODUCTION
1.4 Highlights of the Atlas


Document: GL Atlas Indus 12Nov2020 Final
Section: 2. STUDY AREA > 2.1 Overview
Type: text

The IHR consist of three major river systems of Indus, Ganga, and Brahmaputra, stretches over four countries viz., India, China, Nepal and Bhutan, and on the basis of physiography it has been divided into four mountain regions viz., Eastern Himalayas, Central Himalayas, Western Himalayas, and the Karakoram Mountain range. The Indus River basin is unique in the sense that it contains seven of the world’s highest peaks after Mt. Everest, among these are K2 (8,557 m), Nanga Parbat (8,100 m) and Rakaposhi (7,800 m). The Indus River flowing near Leh (Ladakh) has been shown in Figure 1. The Indus River basin from its origin to foothills of Himalayas has a catchment area of 3,42,841 Km2 (up to Indian administrative boundary). The Indus basin extends over Western Himalayas and Karakoram Mountain range in India, China, and Nepal.

Indus River originates from Bokhar Chu (glacier) in northern slopes of Mt. Kailash (6,714 m) from the Tibet Autonomous Region of China (Husain, 2012; CWC, 2019). The Indus River follows a long and straight course in Ladakh region (flowing in northwest direction in India), running between the Ladakh and the Zaskar ranges. The gradient of the river is also gentle here. It forms a spectacular gorge near Gilgit (at Bunzi, north of Nanga Parbat Glacier) in Jammu & Kashmir. Downstream, the river passes by the Nanga Parbat Glacier, crossing the Himalayas, it turns into south-west and enters Pakistan near Chillar in the Dardistan region. Finally the Indus River drains into the Arabian Sea near the port city of Karachi, Pakistan after forming a huge delta. It has a total length of 2,880 Km, of which 709 Km lies in India. The present study area extends from latitude 30.32° N to 37.09° N and from longitude 72.50° E to 82.45° E.


Document: GL Atlas Indus 12Nov2020 Final
Section: 2. STUDY AREA > 2.2 Hydrological Divide
Type: text

Major rivers flowing in the Indus River basin are Satluj, Beas, Ravi, Chenab, Jhelum, and Zaskar joining the main river on the left, whereas rivers like Sengee Tsangpo, Shyok, and Gilgit joining on the right. Considering hydrological setting of the aforesaid rivers, Indus River basin is divided in 9 subbasins viz., Gilgit, Indus Middle, Jhelum, Chenab, Ravi, Beas, Shyok, Indus Upper, and Satluj. Shyok River is the largest tributary of all (640 Km long). Figure 2 shows the location of the study area with Resourcesat-2 (RS-2) Linear Imaging Self Scanner (LISS IV) satellite images. Table 1 shows the area covered by each of the above subbasins.

Beas
Chenab
Gilgit
Indus Middle
Indus Upper
Jhelum
Ravi
Satluj
Shyok


Document: GL Atlas Indus 12Nov2020 Final
Section: 2. STUDY AREA > 2.2 Hydrological Divide
Type: table
Table: Table 1: Details of subbasins of Indus River basin

| S. No. | Subbasin | Area (Km2) | Area (%) |
|---|---|---|---|
| 1 | Beas | 13,963 | 4.07 |
| 2 | Chenab | 29,258 | 8.53 |
| 3 | Gilgit | 27,397 | 7.99 |
| 4 | Indus Middle | 23,703 | 6.91 |
| 5 | Indus Upper | 72,695 | 21.20 |
| 6 | Jhelum | 29,388 | 8.57 |
| 7 | Ravi | 9,237 | 2.69 |
| 8 | Satluj | 57,560 | 16.79 |
| 9 | Shyok | 79,640 | 23.23 |
| | **Total** | **342,841** | **100.00** |


Document: GL Atlas Indus 12Nov2020 Final
Section: 2. STUDY AREA > 2.3 Hydrology
Type: text

All the principal tributaries of the Indus River system are fed by snow and glaciers in the upper parts of their mountainous catchments. The snow accumulation in their upper catchments usually starts from October to March months reaching peak in January/February. The river flows are at minimum during the winter months of December to March. When snow and glaciers start melting during summer months of April to June, river flows gradually increase and accelerated further by rainy season of July to September. Annually, the upper Indus carries about 110 Billion Cubic Metre (BCM) slightly less than half the total supply of water in the Indus River system. The Jhelum and Chenab combined carry roughly one-fourth, and the Ravi, Beas, and Satluj combined constitute the remainder of the total supply of the system.

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN


Document: GL Atlas Indus 12Nov2020 Final
Section: 2. STUDY AREA > 2.4 Topography
Type: text

The elevation of the study area ranges between 153 m and 8,557 m above mean sea level (amsl), where glaciers and glacial lakes are mostly distributed in the higher altitude region. The mean elevation of the study area is 4,355 m amsl. The transverse glaciers present in the basin at different locations and occasional landslides may also dam the river resulting in formation of temporary lakes. Downwards, the Indus crosses the Central Himalayan Range through a huge synclinal gorge. The Indus makes several deep gorges, amongst which the deepest of all is at Gilgit, which is 5,200 m in height amsl. Slope in the entire study area varies up to a maximum of 87.76°, while the mean slope in the Indus River basin is 22.23°. Hypsometric curve is a graph which shows the proportion of land area that exist at various elevations by plotting relative area against relative height, as shown in Figure 3 for the study area.


Document: GL Atlas Indus 12Nov2020 Final
Section: 2. STUDY AREA > 2.4 Topography
Type: figure
Figure: Figure 3: Hypsometric curve of the study area

Figure 3: Hypsometric curve of the study area


Document: GL Atlas Indus 12Nov2020 Final
Section: 2. STUDY AREA > 2.5 Climate
Type: text

Climate over the Indus River basin varies from subtropical arid and semiarid to temperate subhumid on the plains of Sindh and Punjab provinces to alpine in the mountainous highlands of the north. Annual precipitation ranges between 100 and 500 mm in the lowlands to a maximum of 2,000 mm on mountain slopes. In the lower plains, December to February is the cold season and mean monthly temperatures vary from 14°C to 20°C. Mean monthly temperatures during March to June vary from 42°C to 44°C. Whereas, in the upper plains mean temperature ranges from 23°C to 49°C during summer and from 2°C to 23°C during winter.

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN


Document: GL Atlas Indus 12Nov2020 Final
Section: 3. DATA USED
Type: text

Earth observation satellites capture the data repeatedly in various spectral ranges and at different spatial and radiometric resolutions. For inventorying glacial lakes, high to medium resolution datasets are proved to be useful by many research studies (Bolch et al., 2010; Mergili et al., 2013; Wang et al., 2013; Zhang et al., 2015; Gupta et al., 2019; Guru et al., 2019). Data captured between September and December were mostly used because the presence of snow or cloud cover during this period is minimum. USGS satellite data of Landsat 5 and 7 (TM and ETM+) has been used widely for mapping glacial lakes due to free accessibility. Whereas, IRS satellite data from sensors of AWiFS, LISS-III, LISS-IV has also been used for such inventory.

In the present study, high resolution Resourcesat-2 LISS-IV satellite images with spatial resolution of 5.8 m covering a swath of 70 × 70 Km have been used for inventorying glacial lakes. Maximum of the images used for inventorying were of 2016-17 (66%) and remaining images procured were of previous years due to non-availability of cloud-free and snow-free images for the recent years. Majority of images were of September and December months (80%) due to less snow and cloud cover, and rest 20% images of other months. Figure 4 shows the layout of the RS-2 LISS-IV scenes (path-wise) procured for the Indus River basin along with its details in Table 2. The layout of satellite scenes is divided into paths (shown in separate colours) and rows (row numbers shown in the layout).

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GLACIAL LAKE ATLAS OF INDUS RIVER BASIN


Document: GL Atlas Indus 12Nov2020 Final
Section: 3. DATA USED
Type: table
Table: Table 2: Details of satellite scenes used for inventory

| | Other Months | Sep - Dec | Total |
|---|---|---|---|
| Prior to 2016 | 13 | 41 | 54 |
| 2016-17 | 17 | 86 | 103 |
| **Total** | **30** | **127** | **157** |


Document: GL Atlas Indus 12Nov2020 Final
Section: 3. DATA USED
Type: text

Digital Elevation Model (DEM) of Cartosat satellite with 10 m spatial resolution has been used for topographic information and watershed boundary generation. Figure 5 shows elevation range map of the study area i.e. Indus River basin. Other information like name of lakes and rivers has been gathered from digital toposheets available from University of Texas - Toposheet Library at 1:250,000 scale and Tibet Map Institute at 1:100,000 scale (U.S. Army Map Service 1955; Andre 2017).

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN


Document: GL Atlas Indus 12Nov2020 Final
Section: 4. METHODOLOGY > 4.1 Satellite Data Interpretation
Type: text

The spectral reflectance curve of water in the visible spectrum starts with a low in Blue region (0.4 to 0.5 μm), reaches peak in Green region (0.5 to 0.6 μm), decreases in Red region (0.6 to 0.7 μm) and probably the most distinctive characteristic is the energy absorption at Near InfraRed (NIR) wavelengths. Identifying and delineating water bodies with remote sensing data are carried out easily in near infrared wavelengths because of this absorption property in IR region. However, various physical conditions of water bodies (water depth, turbidity, chlorophyll content, etc.) manifest spectral changes. As a result of various conditions of lakes, the water in satellite images in False Colour Composite (FCC) ranges in appearance from light to dark blue to black. In the case of frozen lakes, it appears white.

Glacial lake sizes are generally small, having circular, semi-circular, or elongated shapes with very fine texture and are generally associated with glaciers in high altitude areas. Certain types of glacial lakes, like erosion and cirque lakes are not necessarily associated with glaciers. Knowledge of the physical characteristics of the glacial lakes, and their associated features is always essential for the interpretation of the images.

Satellite data interpretation can be done using visual image interpretation keys such as colour, size, tone, texture, pattern, association, shape, shadow, and orientation. A number of remote sensing methods had been developed for glacial lake detection and mapping or development of inventory (Kääb 2000; Mool et al., 2001a; Huggel et al., 2002; Huggel et al., 2006; Ives et al., 2010). Manual or automated lake mapping methods have certain difficulties in identifying the lakes, which are described in the following section. An attempt was made to study the accuracy of mapping of glacial lakes using multiple automated methods along with visual interpretation, the details of which are given in Annexure-I. From this study, it was concluded that visual interpretation method was best accurate method. Hence, in the present study glacial lakes and their different types are identified and mapped using RS-2 LISS-IV multispectral images using visual interpretation method.

4. METHODOLOGY
4.1 Satellite Data Interpretation


Document: GL Atlas Indus 12Nov2020 Final
Section: 4. METHODOLOGY > 4.1 Satellite Data Interpretation > Difficulties in Lake Identification:
Type: text

Glacial lake identification can be done either using visual interpretation or automatic mapping methods. The automatic mapping procedures have limitations due to varying terrain conditions like lakes situated in the shadow portions of mountains, presence of snow cover, cloud cover, and partly frozen lakes, etc. In the presence of snow cover on the glacier tongue or glacier’s ablation area where many Supra-glacial lakes may present, both methods have limitations and difficulties.

As lake water absorbs the incident radiation making it appear in darker tone and colour in the standard FCC of satellite data, similar response also prevails over shadow region of clouds or mountains on surface, which may lead to incorrect mapping. In fact, a mountain shadow covering a lake partly/completely within its vicinity, making it difficult to accurately map the lake boundary.

Many lakes due to inclement terrain condition, can be under shadow of high peaks and will get missed in both ways of mapping. On the contrary, a lake can also present in white colour while it is in frozen form due to cold weather conditions over the area, then definitely it will not get classified while automatic mapping. Whereas, frozen lakes can be identified and mapped using visual interpretation to some extent.

4. METHODOLOGY
4.1 Satellite Data Interpretation
Difficulties in Lake Identification:


Document: GL Atlas Indus 12Nov2020 Final
Section: 4. METHODOLOGY > 4.1 Satellite Data Interpretation > Challenges in Automatic Mapping:
Type: text

In the IHR, due to high and inclement terrain surface and due to near vertical acquisition of satellite images, some lakes get covered with shadows of mountains, which create problems in identifying glacial lakes. Also identification of lakes with high turbidity, partial ice covered lakes and the lakes in shadow areas are misclassified by automatic methods. Glacial lake mapping is always a semi-automatic approach because even after applying any of that method, it should always be followed by the post processing i.e. correcting the errors using visual interpretation. Even in all cases, automatic mapping will never give the exact and accurate boundary of the lake, leading to necessary manual corrections.

4. METHODOLOGY
4.1 Satellite Data Interpretation
Challenges in Automatic Mapping:


Document: GL Atlas Indus 12Nov2020 Final
Section: 4. METHODOLOGY > 4.1 Satellite Data Interpretation > Reasoning for Visual Interpretation:
Type: text

Although automatic mapping methods can speed up the detection of glacial lakes, but these methods could not be applied to the entire Himalayan region due to lot of variations in satellite scenes (seasons/years) and problems mentioned above. For example, if lakes are frozen or covered with snow or cloud and lies in a shadow area, they cannot be detected using these automatic methods. In such cases, the manual interpretation method will be helpful to map these lakes. Thus, any mapping of glacial lakes can be automated up to a certain extent only. So, visual image interpretation keys and technique will give accurate results and avoids misclassification. Therefore, in this present study, glacial lakes and its type identification, and its mapping for the entire Indus River basin (within IHR) has been done manually using visual interpretation. High resolution satellite data available on Bhuvan/Google Earth has been used on need basis in finalizing various features of glacial lake database.

4. METHODOLOGY
4.1 Satellite Data Interpretation
Reasoning for Visual Interpretation:


Document: GL Atlas Indus 12Nov2020 Final
Section: 4. METHODOLOGY > 4.1 Satellite Data Interpretation > Limitations:
Type: text

The RS-2 LISS-IV MX data used for glacial lake database preparation sporadically covered with cloud and seasonal/permanent snow. Also, the Himalayan region being highly varying topography with steep slopes, the satellite data has hill shadows. Thus few glacial lakes would not have been mapped owing to the following constraints:

*   Presence of snow or cloud over the glacial lakes
*   Glacial lakes under frozen condition
*   Glacial lakes under mountain shadow

4. METHODOLOGY
4.1 Satellite Data Interpretation
Limitations:


Document: GL Atlas Indus 12Nov2020 Final
Section: 4. METHODOLOGY > 4.2 Types of Glacial Lakes
Type: text

Various researchers have proposed glacial lakes classification schemes based on dam type, process of lake formation, topographic feature, and geographical position (Hewitt 1982; Liu and Sharma 1988; Clague and Evans 2000; Mool et al., 2001a, 2001b). Lakes located on the glacier surface can be mapped using satellite data, but there are englacial and subglacial lakes that may also exist, but cannot be mapped from aerial/optical satellite images, requires ground based instrument (Yao et al., 2018). Majorly surface glacial lakes are classified in 4 classes and 10 subclasses, i.e. Moraine-dammed lake, Ice-dammed lake, Glacier Erosion lake (also known

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GLACIAL LAKE ATLAS OF INDUS RIVER BASIN

as Bed-rock lake), and Other Glacial lake. Two character symbol has been used for glacial lake classification, in which first letter (uppercase) represents lake type and second letter (lowercase) within brackets represents lake subtype, for example, M(e) for End-moraine dammed lake. Details of types of lakes are given in Table 3 and their appearance in satellite images are shown in Figure 6.

4. METHODOLOGY
4.2 Types of Glacial Lakes


Document: GL Atlas Indus 12Nov2020 Final
Section: 4. METHODOLOGY > 4.2 Types of Glacial Lakes
Type: figure
Figure: Figure 6: Types of Glacial Lakes

**Figure 6: Types of Glacial Lakes**


Document: GL Atlas Indus 12Nov2020 Final
Section: 4. METHODOLOGY > 4.2 Types of Glacial Lakes
Type: table
Table: Table 3: Glacial lake types and their identification keys

| S. No. | Lake Type | Lake Subtype | Code | Identification Keys |
| :--- | :--- | :--- | :--- | :--- |
| 1 | Moraine-dammed Lake | End-moraine Dammed Lake | M(e) | Lake dammed by end (terminal) moraines |
| 2 | Moraine-dammed Lake | Lateral Moraine Dammed Lake | M(l) | Lake dammed by lateral moraine(s) not in contact with glacial ice |
| 3 | Moraine-dammed Lake | Lateral Moraine Dammed Lake (with Ice) | M(lg) | Lake dammed by lateral moraine(s) in contact with glacial ice |
| 4 | Moraine-dammed Lake | Other Moraine Dammed Lake | M(o) | Lake dammed by other moraines |
| 5 | Ice-dammed Lake | Supra-glacial Lake | I(s) | Pond or lake on the surface of a glacier |
| 6 | Ice-dammed Lake | Glacier Ice-dammed Lake | I(d) | Lake dammed by glacier ice with no lateral moraines |
| 7 | Glacier Erosion Lake | Cirque Erosion Lake | E(c) | A small pond occupying a cirque |
| 8 | Glacier Erosion Lake | Glacier Trough Valley Erosion Lake | E(v) | Lakes formed in the glacier trough as a result of the glacier erosion process |
| 9 | Glacier Erosion Lake | Other Glacial Erosion Lake | E(o) | Bodies of water occupying depressions formed by the glacial erosion process |
| 10 | Other Glacial Lake | Other Glacial Lake | O | Lakes formed in a glaciated valley, and fed by glacial melt, but damming material not directly part of the glacial process |

S. No.
Lake Type
Lake Subtype
Code
Identification Keys


Document: GL Atlas Indus 12Nov2020 Final
Section: 4. METHODOLOGY > 4.2 Types of Glacial Lakes
Type: text

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN


Document: GL Atlas Indus 12Nov2020 Final
Section: 4. METHODOLOGY > 4.2 Types of Glacial Lakes > 4.3 Lake Attribute Information
Type: text

A total of 22 attributes has been given to all mapped lake features in the geodatabase, which are broadly consisting information grouped in six different categories as shows in Table 4.

4. METHODOLOGY
4.2 Types of Glacial Lakes
4.3 Lake Attribute Information


Document: GL Atlas Indus 12Nov2020 Final
Section: 4. METHODOLOGY > 4.2 Types of Glacial Lakes > 4.3 Lake Attribute Information
Type: table
Table: Table 4: Details of glacial lake attributes

| S. No. | Category | Attribute |
| :--- | :--- | :--- |
| 1 | Hydrological | Basin, subbasin, river, lake name |
| 2 | Geometrical | Maximum length, mean width, surface area |
| 3 | Geographical | Latitude, longitude, region, state, district, toposheet 250K, toposheet 50K |
| 4 | Topographical | Elevation, aspect |
| 5 | Lake Information | Feature type, glacial lake type, lake ID |
| 6 | Data Source Information | Source of database, source of elevation, date of pass |


Document: GL Atlas Indus 12Nov2020 Final
Section: 4. METHODOLOGY > 4.2 Types of Glacial Lakes > 4.3 Lake Attribute Information
Type: text

Typically, lake ID is given in 12 alpha-numeric character format like "0142H0300080", where first two digits '01' refers to Basin code which is Indus (02-Ganga and 03-Brahmaputra), next five characters '42H03' refers to the 1:250,000 (42H) and 1:50,000 (42H03) scale SOI Toposheet number, and the last five digits refers to the sequential number of each lake sorted from top left to bottom right. A typical example of the glacial lake database generated is given below in Table 5 along with fields and format.


Document: GL Atlas Indus 12Nov2020 Final
Section: 4. METHODOLOGY > 4.2 Types of Glacial Lakes > 4.3 Lake Attribute Information
Type: table
Table: Table 5: Typical example of glacial lake attribute database

| S. No. | Database Fields | Type | Format / Unit | Lake Attribute |
| :--- | :--- | :--- | :--- | :--- |
| 1 | ID No | String | Text | 0152H1103771 |
| 2 | Toposheet 250K | String | Text | 52H |
| 3 | Toposheet 50K | String | Text | 52H11 |
| 4 | Latitude* | Float | Decimal Degree | 32.499 |
| 5 | Longitude* | Float | Decimal Degree | 77.547 |
| 6 | Basin | String | Text | Indus |
| 7 | Sub Basin | String | Text | Chenab |
| 8 | River | String | Text | Chandra River |
| 9 | Type (GL/WB) | String | Text | Glacial Lake |
| 10 | Name | String | Text | Samudra Tapu Lake |
| 11 | Glacial Lake Type | String | Text | M(e): End-moraine Dammed Lake |
| 12 | Surface Area | Float | ha | 128.69 |
| 13 | Length | Float | Km | 2.381 |
| 14 | Mean Width | Float | Km | 0.821 |
| 15 | Elevation* | Integer | m (amsl) | 4150 |
| 16 | Aspect | String | Text | SE |
| 17 | Source of Database | String | Text | RS-2 LISS-IV |
| 18 | Date of Pass | Date | DDMMYYYY | 05112016 |
| 19 | Source of Elevation | String | Text | Cartosat DEM |
| 20 | Region | String | Text | India |
| 21 | State | String | Text | Himachal Pradesh |
| 22 | District | String | Text | Lahul & Spiti |

S. No.
Database Fields
Type
Format / Unit
Lake Attribute


Document: GL Atlas Indus 12Nov2020 Final
Section: 4. METHODOLOGY > 4.2 Types of Glacial Lakes > 4.3 Lake Attribute Information
Type: text

*Latitude, longitude, and elevation has been taken at the centroid of the lake

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS
Type: text

The mapped glacial lakes are analyzed for their distribution in terms of area, type, and elevation, at basin, subbasin, administrative and transboundary level. Area of mapped glacial lakes is ranging from a minimum of 0.25 ha to a maximum of 262.56 ha. Details of glacial lakes inventoried for the Indus River basin is given in Annexure-II. The results are discussed in subsequent sections:


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.1 Indus Basin Level Statistics
Type: text

**Area range-wise Distribution**

A total of 5,335 glacial lakes (greater than 0.25 ha) were identified and mapped using RS-2 LISS-IV images for the entire Indus River basin, with a total lake water spread area of 17,395.03 ha. Table 6 and Figure 7 shows the area range-wise distribution of glacial lakes for the entire basin. About 4,633 (86.84%) lakes are with < 5 ha lake area contributing to 34.04% of total lake area. The remaining lakes with > 5 ha in size are 702 (13.16%) contributing to 65.96% of total lake area in the basin. Details of lakes > 50 ha is given in Annexure-III.

5. RESULTS
5.1 Indus Basin Level Statistics


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.1 Indus Basin Level Statistics
Type: table
Table: Table 6: Area range-wise distribution of Glacial Lakes (GL) in Indus River basin

| S. No. | Lake Area Range (ha) | No. of Lakes | Total Lake Area (ha) | Total Lake Area (%) |
|---|---|---|---|---|
| 1 | 0.25 - 0.5 | 1,378 | 496.93 | 2.86 |
| 2 | 0.5 - 1 | 1,239 | 877.42 | 5.04 |
| 3 | 1 - 5 | 2,016 | 4,546.28 | 26.14 |
| 4 | 5 - 10 | 381 | 2,647.29 | 15.22 |
| 5 | 10 - 50 | 287 | 5,302.84 | 30.48 |
| 6 | > 50 | 34 | 3,524.27 | 20.26 |
| | **Total** | **5,335** | **17,395.03** | **100.00** |

S. No.
Lake Area Range (ha)
No. of Lakes
Total Lake Area (ha)
Total Lake Area (%)


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.1 Indus Basin Level Statistics
Type: text

***

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN

**Type-wise Distribution**

Distribution of different types of glacial lakes in the entire Indus River basin is given in Table 7 and Figure 8. Out of 10 types of glacial lakes, Other Glacial Erosion lakes are found to be the maximum with 2,516 (47.16%) occupying a total lake extent of 8,247.44 ha at 47.42% in the basin. Two other types of lake, namely, Other Moraine Dammed and Supra-glacial lake are 905 (16.96%) and 809 (15.16%), extend over an area of 1,212.40 ha (6.97%) and 609.05 ha (3.50%) respectively.


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.1 Indus Basin Level Statistics
Type: table
Table: Table 7: Type-wise distribution of GL in Indus River basin

| S. No. | Code | GL Type | No. of Lakes | Total Lake Area (ha) | Total Lake Area (%) |
|---|---|---|---|---|---|
| 1 | M(e) | End-moraine Dammed Lake | 407 | 2,267.29 | 13.03 |
| 2 | M(l) | Lateral Moraine Dammed Lake | 225 | 317.59 | 1.83 |
| 3 | M(lg) | Lateral Moraine Dammed Lake with Ice | 45 | 111.92 | 0.64 |
| 4 | M(o) | Other Moraine Dammed Lake | 905 | 1,212.40 | 6.97 |
| 5 | I(s) | Supra-glacial Lake | 809 | 609.05 | 3.50 |
| 6 | I(d) | Glacier Ice-dammed Lake | 2 | 234.53 | 1.35 |
| 7 | E(c) | Cirque Erosion Lake | 220 | 1,971.43 | 11.33 |
| 8 | E(v) | Glacier Trough Valley Erosion Lake | 2 | 17.25 | 0.10 |
| 9 | E(o) | Other Glacial Erosion Lake | 2,516 | 8,247.44 | 47.42 |
| 10 | O | Other Glacial Lake | 204 | 2,406.12 | 13.83 |
| | | **Total** | **5,335** | **17,395.03** | **100.00** |

S. No.
Code
GL Type
No. of Lakes
Total Lake Area (ha)
Total Lake Area (%)


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.1 Indus Basin Level Statistics
Type: text

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN

**Area range-Type-wise Distribution**

Glacial lake distribution by area range vs. type-wise is given in Table 8 and Figure 9. The lakes with < 5 ha in size (86.84%) are dominant with Other Glacial Erosion lake type (46.1%) followed by Other Moraine Dammed (18.8%) and Supra-glacial lake (17.2%). The lakes with > 5 ha (13.16%) are also dominated by Other Glacial Erosion lakes (54.1%) with remaining 9 types together contributing to 45.9%. All types of Moraine-dammed glacial lakes, which constitute about 29.64% are predominantly with < 5 ha in water spread.


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.1 Indus Basin Level Statistics
Type: table
Table: Table 8: Area range-wise vs. Type-wise distribution of GL in Indus River basin

| S. No. | Lake Area Range (ha) | M(e) | M(l) | M(lg) | M(o) | I(s) | I(d) | E(c) | E(v) | E(o) | O | Total |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 0.25 - 0.5 | 49 | 74 | 13 | 333 | 432 | 0 | 7 | 0 | 431 | 39 | 1,378 |
| 2 | 0.5 - 1 | 44 | 69 | 5 | 261 | 263 | 0 | 14 | 0 | 528 | 55 | 1,239 |
| 3 | 1 - 5 | 200 | 71 | 22 | 276 | 102 | 1 | 103 | 1 | 1,177 | 63 | 2,016 |
| 4 | 5 - 10 | 60 | 6 | 3 | 27 | 10 | 0 | 47 | 0 | 215 | 13 | 381 |
| 5 | 10 - 50 | 49 | 5 | 2 | 7 | 2 | 0 | 44 | 1 | 156 | 21 | 287 |
| 6 | > 50 | 5 | 0 | 0 | 1 | 0 | 1 | 5 | 0 | 9 | 13 | 34 |
| **Total** | | **407** | **225** | **45** | **905** | **809** | **2** | **220** | **2** | **2,516** | **204** | **5,335** |

S. No.
Lake Area Range (ha)
M(e)
M(l)
M(lg)
M(o)
I(s)
I(d)
E(c)
E(v)
E(o)
O
Total


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.1 Indus Basin Level Statistics
Type: text

***

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN

**Elevation range-wise Distribution**

Elevation ranges over the entire study area has been classified into four different categories viz., low altitude (up to 3,000 m), medium altitude (3,001 - 4,000 m), high altitude (4,001 - 5,000 m), and very high altitude (> 5,000 m). Table 9 and Figure 10 shows the distribution of the glacial lakes in the Indus basin as per elevation range-wise. Majority of glacial lakes are situated above 4,000 m elevation i.e. 4,657 (87.29% of the total lake count) with total lake area of 14,007.46 ha (80.53%) and remaining 12.71% glacial lakes are below 4,000 m elevation.


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.1 Indus Basin Level Statistics
Type: table
Table: Table 9: Elevation range-wise distribution of GL in Indus River basin

| S. No. | Elevation Range (m) | No. of Lakes | Total Lake Area (ha) | Total Lake Area (%) |
|---|---|---|---|---|
| 1 | up to 3,000 | 21 | 47.70 | 0.27 |
| 2 | 3,001 - 4,000 | 657 | 3,339.87 | 19.20 |
| 3 | 4,001 - 5,000 | 2,797 | 8,301.35 | 47.73 |
| 4 | > 5,000 | 1,860 | 5,706.11 | 32.80 |
| **Total** | | **5,335** | **17,395.03** | **100.00** |

S. No.
Elevation Range (m)
No. of Lakes
Total Lake Area (ha)
Total Lake Area (%)


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.1 Indus Basin Level Statistics
Type: text

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > 5.2.1 Beas Subbasin
Type: text

The Beas subbasin of the Indus River basin is the second smallest subbasin amongst all, covering a total area of 13,963 Km² i.e. 4.07% of the total basin area (Figure 14). One of its major tributary is Parbati River which flows in the upstream area of the subbasin before it confluence with Beas River at Bhuntar of Kullu District of Himachal Pradesh. A total of 96 glacial lakes has been mapped, covering a total area of 143.83 ha i.e. 0.01% of the total area of the subbasin.

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN

**Area range-wise Distribution**

In Beas subbasin, glacial lakes has been distributed in 4 different classes of area ranges viz., 0.25 - 0.5 ha, 0.5 - 1 ha, 1 - 5 ha, and 5 - 10 ha. Table 12 and Figure 15 shows the area-wise distribution of glacial lakes for the Beas subbasin. About 92 (95.83%) lakes are with < 5 ha lake area contributing to 76.36% of total lake area. The remaining lakes with > 5 ha in size are only 4 (4.17%) contributing to 23.64% of total lake area in the subbasin.

5. RESULTS
5.2 Subbasin-Wise Statistics
5.2.1 Beas Subbasin


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > 5.2.1 Beas Subbasin
Type: table
Table: Table 12: Area range-wise distribution of GL in Beas subbasin

| S. No. | Lake Area Range (ha) | No. of Lakes | Total Lake Area (ha) | Total Lake Area (%) |
|---|---|---|---|---|
| 1 | 0.25 - 0.5 | 25 | 9.23 | 6.42 |
| 2 | 0.5 - 1 | 24 | 16.27 | 11.31 |
| 3 | 1 - 5 | 43 | 84.33 | 58.63 |
| 4 | 5 - 10 | 4 | 34.00 | 23.64 |
| 5 | 10 - 50 | 0 | 0.00 | 0.00 |
| 6 | > 50 | 0 | 0.00 | 0.00 |
| | **Total** | **96** | **143.83** | **100.00** |


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > 5.2.1 Beas Subbasin
Type: text

***

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN

**Type-wise Distribution**

Distribution of different types of glacial lakes in the Beas subbasin is given in Table 13 and Figure 16. Out of 10 types of glacial lakes, only 6 types of lake are present in the Beas subbasin, where Other Glacial Erosion lakes are found to be the maximum with 41 (42.71%) occupying a total lake extent of 64.49 ha at 44.84% in the subbasin. Other Moraine Dammed lakes are second majority of lakes i.e. 39 (40.63%) and extend over an area of 37.58 ha (26.13%).


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > 5.2.1 Beas Subbasin
Type: table
Table: Table 13: Type-wise distribution of GL in Beas subbasin

| S. No. | Code | GL Type | No. of Lakes | Total Lake Area (ha) | Total Lake Area (%) |
|---|---|---|---|---|---|
| 1 | M(e) | End-moraine Dammed Lake | 8 | 31.95 | 22.21 |
| 2 | M(o) | Other Moraine Dammed Lake | 39 | 37.58 | 26.13 |
| 3 | I(s) | Supra-glacial Lake | 5 | 6.49 | 4.51 |
| 4 | E(c) | Cirque Erosion Lake | 1 | 2.52 | 1.75 |
| 5 | E(o) | Other Glacial Erosion Lake | 41 | 64.49 | 44.84 |
| 6 | O | Other Glacial Lake | 2 | 0.81 | 0.56 |
| | | **Total** | **96** | **143.83** | **100.00** |


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > 5.2.1 Beas Subbasin
Type: text

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Area range-Type-wise Distribution
Type: text

Glacial lake distribution by area range vs. type-wise is given in Table 14 and Figure 17. The lakes with < 5 ha in size (95.83%) are dominant equally with Other Glacial Erosion lake (42.40%) and Other Moraine Dammed lake type (42.40%). Lakes with > 5 ha (4.17%) are also dominated equally by Other Glacial Erosion (50.00%) and End-moraine Dammed lakes (50.00%). All types of Moraine-dammed lakes, which constitute about 48.95% are predominantly with < 5 ha in water spread.

5. RESULTS
5.2 Subbasin-Wise Statistics
Area range-Type-wise Distribution


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Area range-Type-wise Distribution
Type: table
Table: Table 14: Area range-wise vs. Type-wise distribution of GL in Beas subbasin

| S. No. | Lake Area Range (ha) | M(e) | M(l) | M(lg) | M(o) | I(s) | I(d) | E(c) | E(v) | E(o) | O | Total |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 0.25 - 0.5 | 2 | 0 | 0 | 16 | 0 | 0 | 0 | 0 | 6 | 1 | 25 |
| 2 | 0.5 - 1 | 0 | 0 | 0 | 9 | 0 | 0 | 0 | 0 | 14 | 1 | 24 |
| 3 | 1 - 5 | 4 | 0 | 0 | 14 | 5 | 0 | 1 | 0 | 19 | 0 | 43 |
| 4 | 5 - 10 | 2 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 2 | 0 | 4 |
| 5 | 10 - 50 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| 6 | > 50 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| | **Total** | **8** | **0** | **0** | **39** | **5** | **0** | **1** | **0** | **41** | **2** | **96** |


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Area range-Type-wise Distribution
Type: figure
Figure: Figure 17: Area range-wise vs. Type-wise distribution of GL in Beas subbasin

**Figure 17: Area range-wise vs. Type-wise distribution of GL in Beas subbasin**


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Area range-Type-wise Distribution
Type: text

***

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Elevation range-wise Distribution
Type: text

Elevation range-wise distribution of the glacial lakes in the Beas subbasin has been shown in Table 15 and Figure 18. Majority of glacial lakes are situated above 4,000 m elevation i.e. 93 (96.87% of the total lake count) with total lake area of 142.60 ha (99.15%) and remaining 3.13% glacial lakes are below 4,000 m elevation.

5. RESULTS
5.2 Subbasin-Wise Statistics
Elevation range-wise Distribution


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Elevation range-wise Distribution
Type: table
Table: Table 15: Elevation range-wise distribution of GL in Beas subbasin

| S. No. | Elevation Range (m) | No. of Lakes | Total Lake Area (ha) | Total Lake Area (%) |
|---|---|---|---|---|
| 1 | up to 3,000 | 0 | 0.00 | 0.00 |
| 2 | 3,001 - 4,000 | 3 | 1.23 | 0.85 |
| 3 | 4,001 - 5,000 | 91 | 141.36 | 98.28 |
| 4 | > 5,000 | 2 | 1.25 | 0.87 |
| | **Total** | **96** | **143.83** | **100.00** |


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Elevation range-wise Distribution
Type: figure
Figure: Figure 18: Elevation range-wise distribution of GL in Beas subbasin

**Figure 18: Elevation range-wise distribution of GL in Beas subbasin**


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Elevation range-wise Distribution
Type: text

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Area-Elevation range-wise Distribution
Type: text

Glacial lake distribution has been analyzed as per area range vs. elevation range-wise, given in Table 16 and Figure 19. It is noted that, 94.79% of glacial lakes (91) are situated in high altitude range i.e. 4,001 - 5,000 m amsl, which also constitutes maximum total lake area within that range i.e. 98.28%. However, very few glacial lakes (only 2) lies above 5,000 m, which are within 0.5 - 1 ha lake area range. Maximum of lakes lying in high altitude range is of size ranging 1 - 5 ha (i.e. 43), followed by lakes of size 0.25 - 0.5 ha (i.e. 23).

5. RESULTS
5.2 Subbasin-Wise Statistics
Area-Elevation range-wise Distribution


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Area-Elevation range-wise Distribution
Type: table
Table: Table 16: Area range-wise vs. Elevation range-wise distribution of GL in Beas subbasin

| S. No. | Lake Area Range (ha) | Elevation Range (m): up to 3,000 - No. of lakes | Elevation Range (m): up to 3,000 - Total Lake Area (ha) | Elevation Range (m): 3,001 - 4,000 - No. of lakes | Elevation Range (m): 3,001 - 4,000 - Total Lake Area (ha) | Elevation Range (m): 4,001 - 5,000 - No. of lakes | Elevation Range (m): 4,001 - 5,000 - Total Lake Area (ha) | Elevation Range (m): > 5,000 - No. of lakes | Elevation Range (m): > 5,000 - Total Lake Area (ha) | Total: No. of lakes | Total: Lake Area (ha) |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 0.25 - 0.5 | 0 | 0.00 | 2 | 0.68 | 23 | 8.55 | 0 | 0.00 | 25 | 9.23 |
| 2 | 0.5 - 1 | 0 | 0.00 | 1 | 0.55 | 21 | 14.48 | 2 | 1.25 | 24 | 16.27 |
| 3 | 1 - 5 | 0 | 0.00 | 0 | 0.00 | 43 | 84.33 | 0 | 0.00 | 43 | 84.33 |
| 4 | 5 - 10 | 0 | 0.00 | 0 | 0.00 | 4 | 34.00 | 0 | 0.00 | 4 | 34.00 |
| 5 | 10 - 50 | 0 | 0.00 | 0 | 0.00 | 0 | 0.00 | 0 | 0.00 | 0 | 0.00 |
| 6 | > 50 | 0 | 0.00 | 0 | 0.00 | 0 | 0.00 | 0 | 0.00 | 0 | 0.00 |
| Total | | 0 | 0.00 | 3 | 1.23 | 91 | 141.36 | 2 | 1.25 | 96 | 143.83 |


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Area-Elevation range-wise Distribution
Type: figure
Figure: Figure 19: Area range-wise vs. Elevation range-wise distribution of GL in Beas subbasin

**Figure 19: Area range-wise vs. Elevation range-wise distribution of GL in Beas subbasin**


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Area-Elevation range-wise Distribution
Type: text

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Type-Elevation range-wise Distribution
Type: text

Glacial lake distribution has also been analyzed as per type-wise vs. elevation range-wise, given in Table 17 and Figure 20. The dominant lake types in the basin i.e., Other Glacial Erosion lakes (42.40% in number and 44.84% in extent) are predominantly located in the elevation range of 4,001 - 5,000 m (40.66%). The other dominant lake type, namely, Other Moraine Dammed lakes are distributed completely in 4,001 - 5,000 m elevation range which constitutes 48.95% of the total lakes. Elevation range-type-wise distribution of glacial lakes has been represented in Figure 21.

5. RESULTS
5.2 Subbasin-Wise Statistics
Type-Elevation range-wise Distribution


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Type-Elevation range-wise Distribution
Type: table
Table: Table 17: Type-wise vs. Elevation range-wise distribution of GL in Beas subbasin

| S. No. | Elevation Range (m) | Types of Glacial Lake: M(e) | Types of Glacial Lake: M(l) | Types of Glacial Lake: M(lg) | Types of Glacial Lake: M(o) | Types of Glacial Lake: I(s) | Types of Glacial Lake: I(d) | Types of Glacial Lake: E(c) | Types of Glacial Lake: E(v) | Types of Glacial Lake: E(o) | Types of Glacial Lake: O | Total |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | up to 3,000 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| 2 | 3,001 - 4,000 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 2 | 1 | 3 |
| 3 | 4,001 - 5,000 | 8 | 0 | 0 | 39 | 5 | 0 | 1 | 0 | 37 | 1 | 91 |
| 4 | > 5,000 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 2 | 0 | 2 |
| Total | | 8 | 0 | 0 | 39 | 5 | 0 | 1 | 0 | 41 | 2 | 96 |

S. No.
Elevation Range (m)
Types of Glacial Lake: M(e)
Types of Glacial Lake: M(l)
Types of Glacial Lake: M(lg)
Types of Glacial Lake: M(o)
Types of Glacial Lake: I(s)
Types of Glacial Lake: I(d)
Types of Glacial Lake: E(c)
Types of Glacial Lake: E(v)
Types of Glacial Lake: E(o)
Types of Glacial Lake: O
Total


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Type-Elevation range-wise Distribution
Type: figure
Figure: Figure 20: Type-wise vs. Elevation range-wise distribution of GL in Beas subbasin

**Figure 20: Type-wise vs. Elevation range-wise distribution of GL in Beas subbasin**


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Type-Elevation range-wise Distribution
Type: text

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > 5.2.2 Chenab Subbasin
Type: text

The Chenab subbasin is the fifth largest subbasin of the Indus basin covering a total area of 29,257 Km² i.e. 8.53% of the total basin area (Figure 22). Chandra and Bhaga Rivers are the two main tributaries of Chenab subbasin, and with the confluence of both rivers at Tandi in Lahul & Spiti District of Himachal Pradesh (place known as Chandra-Bhaga Sangam), from where the Chenab River starts. Later the Chenab subbasin also have two other tributaries viz., Bhut and Warwan (Marau), both joins the Chenab River from the right, at Paddar and Bandarkoot respectively, both in Kishtwar district of Jammu and Kashmir. A total of 397 glacial lakes has been mapped, covering a total area of 896.11 ha i.e. 0.03% of the total area of the subbasin.

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN

5. RESULTS
5.2 Subbasin-Wise Statistics
5.2.2 Chenab Subbasin


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Area range-wise Distribution
Type: text

In Chenab subbasin, glacial lakes have been distributed in all 6 classes of area ranges. Table 18 and Figure 23 shows the area range-wise distribution of glacial lakes for the Chenab subbasin. About 367 (92.44%) lakes are with < 5 ha lake area contributing to 40.48% of total lake area. The remaining lakes with > 5 ha in size are only 30 (7.56%) contributing to 59.52% of total lake area in the subbasin.

5. RESULTS
5.2 Subbasin-Wise Statistics
Area range-wise Distribution


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Area range-wise Distribution
Type: table
Table: Table 18: Area range-wise distribution of GL in Chenab subbasin

| S. No. | Lake Area Range (ha) | No. of Lakes | Total Lake Area (ha) | Total Lake Area (%) |
|---|---|---|---|---|
| 1 | 0.25 - 0.5 | 152 | 54.27 | 6.06 |
| 2 | 0.5 - 1 | 99 | 68.51 | 7.65 |
| 3 | 1 - 5 | 116 | 239.99 | 26.78 |
| 4 | 5 - 10 | 21 | 147.32 | 16.44 |
| 5 | 10 - 50 | 7 | 179.72 | 20.06 |
| 6 | > 50 | 2 | 206.28 | 23.02 |
| | **Total** | **397** | **896.11** | **100.00** |


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Area range-wise Distribution
Type: text

***

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Type-wise Distribution
Type: text

Distribution of different types of glacial lakes in the Chenab subbasin is given in Table 19 and Figure 24. Out of 10 types of glacial lakes, only 7 types of lake are present in the Chenab subbasin, where Other Glacial Erosion lakes are found to be the maximum with 128 (32.24%) occupying a total lake area extent of 211.03 ha at 23.55% in the subbasin. Two other types of lake, namely, Other Moraine Dammed and Supra-glacial lakes are 97 (24.43%) and 85 (21.41%) and extend over lake area of 86.83 ha (9.69%) and 50.45 ha (5.63%) respectively.

5. RESULTS
5.2 Subbasin-Wise Statistics
Type-wise Distribution


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Type-wise Distribution
Type: table
Table: Table 19: Type-wise distribution of GL in Chenab subbasin

| S. No. | Code | GL Type | No. of Lakes | Total Lake Area (ha) | Total Lake Area (%) |
|---|---|---|---|---|---|
| 1 | M(e) | End-moraine Dammed Lake | 32 | 349.36 | 38.99 |
| 2 | M(l) | Lateral Moraine Dammed Lake | 26 | 22.76 | 2.54 |
| 3 | M(o) | Other Moraine Dammed Lake | 97 | 86.83 | 9.69 |
| 4 | I(s) | Supra-glacial Lake | 85 | 50.45 | 5.63 |
| 5 | E(c) | Cirque Erosion Lake | 24 | 152.29 | 16.99 |
| 6 | E(o) | Other Glacial Erosion Lake | 128 | 211.03 | 23.55 |
| 7 | O | Other Glacial Lake | 5 | 23.39 | 2.61 |
| | | **Total** | **397** | **896.11** | **100.00** |


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Type-wise Distribution
Type: text

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN

**Area range-Type-wise Distribution**

Glacial lake distribution by area range vs. type-wise is given in Table 20 and Figure 25. The lakes with < 5 ha in size (92.44%) are dominant with Other Glacial Erosion (33.52%) and Other Moraine Dammed lake (26.16%). Lakes with > 5 ha (7.56%) are dominated by Cirque Erosion (40.00%) and End-moraine Dammed lakes (33.33%). All types of Glacier Erosion lakes, which constitutes about 56.67% are predominantly with < 5 ha in water spread.


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Type-wise Distribution
Type: table
Table: Table 20: Area range-wise vs. Type-wise distribution of GL in Chenab subbasin

| S. No. | Lake Area Range (ha) | M(e) | M(l) | M(lg) | M(o) | I(s) | I(d) | E(c) | E(v) | E(o) | O | Total |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 0.25 - 0.5 | 5 | 8 | 0 | 37 | 57 | 0 | 0 | 0 | 45 | 0 | 152 |
| 2 | 0.5 - 1 | 4 | 11 | 0 | 29 | 23 | 0 | 2 | 0 | 29 | 1 | 99 |
| 3 | 1 - 5 | 13 | 7 | 0 | 30 | 4 | 0 | 10 | 0 | 49 | 3 | 116 |
| 4 | 5 - 10 | 6 | 0 | 0 | 1 | 1 | 0 | 9 | 0 | 4 | 0 | 21 |
| 5 | 10 - 50 | 2 | 0 | 0 | 0 | 0 | 0 | 3 | 0 | 1 | 1 | 7 |
| 6 | > 50 | 2 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 2 |
| | **Total** | **32** | **26** | **0** | **97** | **85** | **0** | **24** | **0** | **128** | **5** | **397** |


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Type-wise Distribution
Type: figure
Figure: Figure 25: Area range-wise vs. Type-wise distribution of GL in Chenab subbasin

**Figure 25: Area range-wise vs. Type-wise distribution of GL in Chenab subbasin**


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Type-wise Distribution
Type: text

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GLACIAL LAKE ATLAS OF INDUS RIVER BASIN

**Elevation range-wise Distribution**

Elevation range-wise distribution of the glacial lakes in the Chenab subbasin has been shown in Table 21 and Figure 26. Majority of glacial lakes are situated above 4,000 m elevation range i.e. 311 (78.34% of the total lake count) with total lake area of 738.93 ha (82.46%) and remaining 17.54% glacial lakes are below 4,000 m elevation.


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Type-wise Distribution
Type: table
Table: Table 21: Elevation range-wise distribution of GL in Chenab subbasin

| S. No. | Elevation Range (m) | No. of Lakes | Total Lake Area (ha) | Total Lake Area (%) |
|---|---|---|---|---|
| 1 | up to 3,000 | 0 | 0.00 | 0.00 |
| 2 | 3,001 - 4,000 | 86 | 157.17 | 17.54 |
| 3 | 4,001 - 5,000 | 243 | 675.70 | 75.40 |
| 4 | > 5,000 | 68 | 63.24 | 7.06 |
| | **Total** | **397** | **896.11** | **100.00** |


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Type-wise Distribution
Type: figure
Figure: Figure 26: Elevation range-wise distribution of GL in Chenab subbasin

**Figure 26: Elevation range-wise distribution of GL in Chenab subbasin**


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Type-wise Distribution
Type: text

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN

**Area-Elevation range-wise Distribution**

Glacial lake distribution has been analyzed as per area range vs. elevation range-wise, given in Table 22 and Figure 27. It is noted that, 61.21% of glacial lakes (243) are situated in high altitude range i.e. 4,001 - 5,000 m amsl, which also constitutes maximum total lake area within that range i.e. 75.40%. However, 68 glacial lakes lies above 5,000 m, has majority of its lakes are < 5 ha i.e. 97.06%. Maximum lakes lying in high altitude range is of size ranging 0.25 - 0.5 ha (i.e. 87), followed by lakes of size 1 - 5 ha (i.e. 72). It has been further noticed that, 63.33% of lakes > 5 ha are lying within in high altitude range i.e. 4,001 - 5,000 m, majority of them falling in size ranging of 5 - 10 ha.


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Type-wise Distribution
Type: table
Table: Table 22: Area range-wise vs. Elevation range-wise distribution of GL in Chenab subbasin

| S. No. | Lake Area Range (ha) | Elevation up to 3,000 (No. of Lakes) | Elevation up to 3,000 (Total Lake Area (ha)) | Elevation 3,001 - 4,000 (No. of Lakes) | Elevation 3,001 - 4,000 (Total Lake Area (ha)) | Elevation 4,001 - 5,000 (No. of Lakes) | Elevation 4,001 - 5,000 (Total Lake Area (ha)) | Elevation > 5,000 (No. of Lakes) | Elevation > 5,000 (Total Lake Area (ha)) | Total (No. of Lakes) | Total (Lake Area (ha)) |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 0.25 - 0.5 | 0 | 0.00 | 35 | 12.90 | 87 | 30.91 | 30 | 10.46 | 152 | 54.27 |
| 2 | 0.5 - 1 | 0 | 0.00 | 15 | 9.90 | 65 | 44.91 | 19 | 13.71 | 99 | 68.51 |
| 3 | 1 - 5 | 0 | 0.00 | 27 | 60.01 | 72 | 152.04 | 17 | 27.94 | 116 | 239.99 |
| 4 | 5 - 10 | 0 | 0.00 | 7 | 48.63 | 12 | 87.57 | 2 | 11.13 | 21 | 147.32 |
| 5 | 10 - 50 | 0 | 0.00 | 2 | 25.73 | 5 | 153.99 | 0 | 0.00 | 7 | 179.72 |
| 6 | > 50 | 0 | 0.00 | 0 | 0.00 | 2 | 206.28 | 0 | 0.00 | 2 | 206.28 |
| | **Total** | **0** | **0.00** | **86** | **157.17** | **243** | **675.70** | **68** | **63.24** | **397** | **896.11** |


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Type-wise Distribution
Type: figure
Figure: Figure 27: Area range-wise vs. Elevation range-wise distribution of GL in Chenab subbasin

**Figure 27: Area range-wise vs. Elevation range-wise distribution of GL in Chenab subbasin**


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Type-wise Distribution
Type: text

***

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN

**Type-Elevation range-wise Distribution**

Glacial lake distribution has also been analyzed as per type-wise vs. elevation range-wise, given in Table 23 and Figure 28. The dominant lake types in the subbasin i.e., Other Glacial Erosion lakes (32.24%) are predominantly located in the elevation range of 4,001 - 5,000 m (29.63%). The other dominant lake type, namely, Other Moraine Dammed and Supra-glacial lakes are also distributed predominantly in 4,001 - 5,000 m elevation range i.e. 23.87% and 22.63%. 86.45% of all types of Moraine-dammed lakes, lie above 4,000 m elevation. Elevation range-type-wise distribution of glacial lakes has been represented in Figure 29.


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Type-wise Distribution
Type: table
Table: Table 23: Type-wise vs. Elevation range-wise distribution of GL in Chenab subbasin

| S. No. | Elevation Range (m) | M(e) | M(l) | M(lg) | M(o) | I(s) | I(d) | E(c) | E(v) | E(o) | O | Total |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | up to 3,000 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| 2 | 3,001 - 4,000 | 6 | 3 | 0 | 12 | 23 | 0 | 10 | 0 | 31 | 1 | 86 |
| 3 | 4,001 - 5,000 | 24 | 16 | 0 | 58 | 55 | 0 | 14 | 0 | 72 | 4 | 243 |
| 4 | > 5,000 | 2 | 7 | 0 | 27 | 7 | 0 | 0 | 0 | 25 | 0 | 68 |
| | **Total** | **32** | **26** | **0** | **97** | **85** | **0** | **24** | **0** | **128** | **5** | **397** |

S. No.
Elevation Range (m)
M(e)
M(l)
M(lg)
M(o)
I(s)
I(d)
E(c)
E(v)
E(o)
O
Total


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Type-wise Distribution
Type: figure
Figure: Figure 28: Type-wise vs. Elevation range-wise distribution of GL in Chenab subbasin

**Figure 28: Type-wise vs. Elevation range-wise distribution of GL in Chenab subbasin**


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > Type-wise Distribution
Type: text

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN

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GLACIAL LAKE ATLAS OF INDUS RIVER BASIN


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > 5.2.3 Gilgit Subbasin
Type: text

The Gilgit subbasin is the fourth smallest subbasin of the Indus River basin covering a total area of 27,396 Km² i.e. 8.0% of the total basin area (Figure 30). Hunza River is a major tributary of Gilgit subbasin which confluences with the main river from the left at Gilgit in Leh District of Ladakh UT. Gilgit subbasin comprised of Gilgit and Hunza catchment, both share equal area coverage. A total of 1,011 glacial lakes has been mapped, covering a total area of 3,380.27 ha i.e. 0.12% of the total area of the subbasin.

**Area range-wise Distribution**

In Gilgit subbasin, glacial lakes have been distributed in all 6 classes of area ranges. Table 24 and Figure 31 shows the area range-wise distribution of glacial lakes for the Gilgit subbasin. About 887 (87.73%) lakes are with < 5 ha lake area contributing to 33.82% of total lake area. The remaining lakes with > 5 ha in size are only 124 (12.27%) contributing to 66.18% of total lake area in the subbasin.

5. RESULTS
5.2 Subbasin-Wise Statistics
5.2.3 Gilgit Subbasin


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > 5.2.3 Gilgit Subbasin
Type: table
Table: Table 24: Area range-wise distribution of GL in Gilgit subbasin

| S. No. | Lake Area Range (ha) | No. of Lakes | Total Lake Area (ha) | Total Lake Area (%) |
| :--- | :--- | :--- | :--- | :--- |
| 1 | 0.25 - 0.5 | 285 | 100.20 | 2.96 |
| 2 | 0.5 - 1 | 218 | 152.33 | 4.51 |
| 3 | 1 - 5 | 384 | 890.84 | 26.35 |
| 4 | 5 - 10 | 66 | 451.17 | 13.35 |
| 5 | 10 - 50 | 51 | 914.27 | 27.05 |
| 6 | > 50 | 7 | 871.46 | 25.78 |
| | **Total** | **1,011** | **3,380.27** | **100.00** |

S. No.
Lake Area Range (ha)
No. of Lakes
Total Lake Area (ha)
Total Lake Area (%)


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > 5.2.3 Gilgit Subbasin
Type: text

**Type-wise Distribution**

Distribution of different types of glacial lakes in the Gilgit subbasin is given in Table 25 and Figure 32. Out of 10 types of glacial lakes, 9 types of lake are present in the Gilgit subbasin, where Other Glacial Erosion lakes are found to be the maximum with 566 (55.98%) occupying a total lake extent of 1,862.53 ha at 55.10% in the subbasin. After that, Supra-glacial and Other Moraine Dammed lakes are in majority with 200 (19.78%) and 99 (9.79%) and extend over a total area of 168.99 ha (5.00%) and 87.59 ha (2.59%) respectively.


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > 5.2.3 Gilgit Subbasin
Type: table
Table: Table 25: Type-wise distribution of GL in Gilgit subbasin

| S. No. | Code | GL Type | No. of Lakes | Total Lake Area (ha) | Total Lake Area (%) |
| :--- | :--- | :--- | :--- | :--- | :--- |
| 1 | M(e) | End-moraine Dammed Lake | 35 | 72.79 | 2.15 |
| 2 | M(l) | Lateral Moraine Dammed Lake | 29 | 28.93 | 0.86 |
| 3 | M(lg) | Lateral Moraine Dammed Lake with Ice | 4 | 1.52 | 0.04 |
| 4 | M(o) | Other Moraine Dammed Lake | 99 | 87.49 | 2.59 |
| 5 | I(s) | Supra-glacial Lake | 200 | 168.99 | 5.00 |
| 6 | E(c) | Cirque Erosion Lake | 42 | 309.87 | 9.17 |
| 7 | E(v) | Glacier Trough Valley Erosion Lake | 2 | 17.25 | 0.51 |
| 8 | E(o) | Other Glacial Erosion Lake | 566 | 1,862.53 | 55.10 |
| 9 | O | Other Glacial Lake | 34 | 830.91 | 24.58 |
| | | **Total** | **1,011** | **3,380.27** | **100.00** |

S. No.
Code
GL Type
No. of Lakes
Total Lake Area (ha)
Total Lake Area (%)


Document: GL Atlas Indus 12Nov2020 Final
Section: 5. RESULTS > 5.2 Subbasin-Wise Statistics > 5.2.3 Gilgit Subbasin
Type: text

GLACIAL LAKE ATLAS OF INDUS RIVER BASIN