Strategically Planning of Hydroelectric Projects for Reduce the Physical Vulnerability of Landscape in Upper Sutlej Valley, Western Himalayas, India

Abstract

Hydropower’s development in the Himalayas region is major concern because area is prone to the geo hazards. The high vulnerability of physical landscape pays attention on the planning of hydropower’s projects. This qualitative empirical research in western Himalayas, present the vulnerability of region and impacts of hydroelectric projects on physical landscape. The IPCC frame work of vulnerability assessment was used to assess the vulnerability in upper Sutlej valley. The indicator based methodology and Geographic information System (GIS) & Remote Sensing (RS) applications were adopted to highlight the impacts and vulnerability. The strategic buffering equal distance analysis was done and this indicates the ignorance of hydropower planning processes. The GIS mapping indicated the excessive development of hydroelectric projects in single river valley and strategic planning emphasizes to follow aerial equidistance between two projects while introducing hydropower projects in the Sutlej valley or any other valleys of the Himalayas region. The suggested strategy shall control the physical, social and economic losses in study region. In addition, this strategy will work as guidelines to develop hydropower projects in other valleys of the Himalaya.

1. Introduction

Hydropower project not leads to environmental air, soil, water pollution and believed as the source of green energy. But in recent time hydropower’s development become the major concern in Himalayas region because of hazards vulnerability and its impacts [1] Upper Valley of Sutlej River is known for its major hydroelectric projects (25) of different phases and categories which included the 4 projects were commissioned, 4 projects were under construction, 9 were of under commissioned and 6 were of under investigation [2] (Figure 1). The upper valley of River Satluj was highly affected because of landslides incidences. These incidences were common in Himalaya’s region but here frequency of these incidences were very high, It was evident from the previous study that maximum landslides incidences were occurred because of its fragile topography and haphazard development of hydroelectric projects [3]. The active landslides (Sudha Rang Dakhu, Shongtong, Urni, Tapari) were noticed in the region because of the slope failure incidences [4].

Figure 1.

Location of hydroelectric projects in Kinnaur district, upper Satluj Valley.

The social issues were related to the livelihood, properties, horticulture and agriculture losses were also observed in the study region [5]. The main objectives of the research were to observe the physical vulnerability and develop strategic planning of hydroelectric projects development. Vulnerability assessment is basically interaction of exposure, susceptibility and resilience of system. The system exposure indicates the threatening from the environmental and manmade hazards. The susceptibility of system raises its weakness through environment exposure. The resilience of the system is the strategic, technical part of planning where procedures are adopted and suggested to make resilient the system. The indicator ranking based methodology is one of important method to assess the vulnerability of selected region [6]. The cumulative environmental impact assessment methodology was adopted in river valley of western Himalayas region. This includes the study of two important river valley Yamuna, Alaknanda and Satluj river valley. It was evident from the cumulative impact assessments reports that all river valleys have same environment issues (Degradation of physical landscapes and loss of livelihood options) which were results of haphazard hydropower’s development [7]. The identified problems related to the high number of hydropower’s project were found in one river valley without following the any equidistance and buffering of hydro projects. Secondary research also revealed that if we follow the strategy of equidistance and buffers of hydroelectric projects then we can control the physical degradation of landscape [6].

2. Study area

The study region of the upper Satluj valley in Himachal Pradesh was extend from 31⁰ 30′ 12” N to 32⁰ 22′16”N and 77⁰ 40′16″E to79⁰ 13′16″E and also covered the area of 6450km². The study region has high altitude which extended from 1200 m to 6705 m. The valley area was divided into two broad categories on the basis of climatic condition. The upper part of the Satluj valley had the climate types of semi-arid to arid temperate. Lower part of valley has high rainfall (816 mm) and the maximum precipitations (1278 mm) were occurred as a snowfall in upper part of valley. The study region is known for its complexities such as high dissection, low green cover (8%), high degree of slope (80% slope area > 30), high incidences of flash floods and landslides. The temperature of the upper part of valley is very low throughout the year but in winter season (December to February) is 8 degree C and can dip as low as −7 degree C. The highest temperature recorded in tapari was 300c in month of June and average high temperature was 15-200c. March to august. The region is known for its dry fruits (pine nuts; Pinus gerardiana) and apples (Alphonso, Kinnauri apple) orchards based livelihood.

3. Material and methods

Strategically planning of hydroelectric projects for avoiding the physical vulnerability of landscape in Sutlej valley was done on the basis of sensitivity (impacts) and selective indicators. The indicators were selected on the basis of their degree of sensitivity. Slope, aspect, lithology, soil texture, slope profile, relative relief, landslide, flood, earthquakes, social aspect indicators were taken. The indicators were classified into its subclasses and then the adverse impacts were observe, perceived and analyzed on these subclasses. The studied were conducted with in the buffer of 10 km form the main river [8]. The impacts of anthropogenic activities were studied within the buffer of 10 km from the main river. All indicators were studied with in the buffer of 10 km form the main river. The vulnerability index was generated for study area. The vulnerability indexes were analyzed on the basis of impacts and vulnerability relationship. The negative (1) and positive (2) relationship were analyzed on the basis of vulnerability formula (Figure 2) [9].

Figure 2.

Study area upper Satluj Valley district Kinnaur, Himachal Pradesh.

$$\mathrm{Xij}\left(\mathrm{N}\right)=\frac{Max\left(\mathrm{Xij}\right)–\mathrm{Xij}}{Max\left(\mathrm{Xij}\right)-Min\left(\mathrm{Xij}\right)}$$E1

$$\mathrm{Xij}\left(\mathrm{p}\right)=\frac{\mathrm{Xij}-Min\left(\mathrm{Xij}\right)}{Max\left(\mathrm{Xij}\right)-Min\left(\mathrm{Xij}\right)}$$E2

The geographic information system was used to analyze the sub classes. The GIS data based was generated from the Raster and vector data set. The qualitative and quantities values were normalized from 0 to 1. The software of ARC GIS, ERDAS were used to geo processed the raster and vector data set. Slope, slope aspect, slope profile, channel gradient, relative relief were analyzed on the basis of DEM (30 m). Soil texture, geological structure, Lithology map were prepared from the secondary map at the scale of 1:50,000. These parameters were also crossed verified in field with the help of GPS (Global Poisoning System).The different classes of land use land cover were studied on the basis of satellites images (ETM⁺2019; 30 m). Earthquake occurrence maps were prepared on the basis of secondary data (Earthquakes point data from 1901 to 2020) of incorporated research institution for seismology (IRIS) and SJVNL (2020).Rock fall, debris fall, debris slide, rock slide, rock creep and soil creep landslides were identified on the satellite images and ground observation were done with the help of GPS., the numbers of landslide incidences pixels were counted for different parameters such as slope, slope aspect, soil texture and land use to know the landslides status on subclasses of indicators. The comprehensive vulnerability index was used to analyze by using the IPCC, guidelines [10]. The flood incidences and their impact were analyzed through primary survey. The adaptability of the region was analyzed on the basis of adaptive indicators. The indictors were analyzed and quantified on the basis of people perceptions.

During the research period 2015–2020 the five consultative meetings, workshops were conducted in affected project area. The brainstorming, interactions, observations, perceptions were taken to analyzed the adaptive matrix of the region. During these meeting 67 respondents of specialized groups such as civil engineers, environmental engineers, lecturers, environmentalists research scholars and administrative were participated.

All possible layers of raster and vector were overplayed and sensitivity of the region was analyzed. The lithology map was extracted from the geological map of Himalayas at the scale of 1:100000 of geological survey of India (Government of India, 1989).

Soil texture was studied on the basis of field surveys and secondary data. The information was collected from the National Bureau of Soil Sciences (NBSS), and soil texture map was prepared at 1:50,000.

4. Result and discussion

$$\mathrm{VI}=\frac{\sum \left(\mathrm{Xij}\right)\mathrm{p}+\sum \left(\mathrm{Xij}\right)\mathrm{n}}{\mathrm{K}}$$

$$\text{Vulnerability in lower zone}\left(\mathrm{VI}\right)=7.5$$

4.1 Slope

The slope is one of the important indicators which indicated the sensitivity of physical loss. Higher slope degree results in rapid runoff and increased erosion rate (potential soil loss) with less ground water recharge potential [11]. The slope of the study area was classified into gentle, moderate, moderate steep, steep, very steep and vertical. The highest affected area was found under the steep, very steep and vertical. The vulnerability and physical landscape have positive relationship on the steep (0.51), very steep (0.51) and vertical slope (1). The negative relationship was found on the gentle (0) and moderate slope (0.34) which indicated the low sensitivity with low vulnerability (Table 1).

Indicators	Classification	Sensitivity (AV)	Relationship	Vulnerability (NV)	Rank relationship
1. Slope	Gentle (0°-5°)	0.24	(−)	0	1^(−)
	Moderate (5°-10°)	0.58	(−)	0.34	2^(−)
	Moderate Steep (10°-18°)	3.71	(+)	0.24	4^(+)
	Steep (18°-30°)	7.44	(+)	0.51	3^(+)
	Very steep (30°-45°)	7.53	(+)	0.51	2^(+)
	Vertical (45°-90°)	14.3	(+)	1	1^(+)
2. Slope aspect	Flat	0	(−)	0	5^(−)
	North	2.28	(−)	0.88	3^(−)
	North East	6.05	(−)	0.31	4^(−)
	East	10.9	(+)	0.75	2^(+)
	South East	12.1	(+)	0.84	3^(+)
	South	14.2	(+)	1	1^(+)
	South West	2.31	(−)	0.86	2^(−)
	West	7.95	(+)	0.53	4^(+)
	North West	0.69	(−)	0.95	1^(−)
3. Lithology	(Pt1) Regionally metamorphosed	5.61	(+)	1	2
	(Pt3e) Greenish gray sandstone	1.79	(−)	0.18	2^(−)
	(Y) Granite &granitoid	0.91	(+)	0	4^(+)
	(Pg3o) Boulder conglomerate sandstone, shale, clay	4.1	(+)	0.67	2^(+)
	(OC) Limestone, Siltstone, shale	3.1	(−)	0.53	1^(−)
	(Pt23) Slate, Phyllite, quartzite, gray shale	2.7	(+)	0.38	3^(+)
	(Pt2) Ortho quartzite, basic volcanic & limestone /dolomite	4.39	(+)	0.74	1^(+)
4. Soil texture	Coarse Texture	3.6	(−)	0.16	2^(−)
	Fine Texture	6.71	(+)	0.39	2^(+)
	Medium Texture	1.31	(−)	0	1^(−)
	Rocky / bad land	13.41	(+)	1	1^(+)
5. LULC	Settlements	0.21	(+)	0.0075	7^(+)
	Agricultural land	10.8	(+)	0.73	4^(+)
	Forest cover	10.2	(+)	0.69	5^(+)
	Barren / Wasteland	14.1	(+)	0.96	2^(+)
	Grass / grazing	14.6	(+)	1	1^(+)
	Scrubland	1.46	(−)	0.093	3^(−)
	Water bodies	2.23	(−)	0.14	6^(−)
	Snow and glacier	0.1	(−)	0	8^(−)
6. Slope profile	Summital convexity	3.1	(+)	0.26	4^(+)
	Rectilinear section	2.5	(+)	0.42	3^(+)
	Free face	1.7	(−)	1	2^(−)
	Basal concavity	3.6	(+)	1	1^(+)
7. Relative relief	RR 4011	10.8	(+)	0.74	2^(+)
	RR 6014	3.2	(−)	0.24	1^(−)
8. River morphological	Channel Slope gradients	11.5	(+)	0	2^(+)
	Channel Slope gradients	15.7	(+)	1	1^(+)
9. Landslides	Large (21)	21	(−)	1	2
	Landslides(90)	90	(+)	1	1
10. Flood	1 Order streams	2	(−)	0	4^(−)
	2rd Order streams	8	(−)	0.5	3^(−)
	3rd Order streams	11	(+)	0.75	2^(+)
	4rd Order streams	14	(+)	1	1^(+)
11. Earthquakes	Faults	12.7	(+)	1	1^(+)
	MCT/Thrusts	11.4	(+)	8.3	2^(+)
	M ∼ 6.1	6.4	(+)	0.58	3^(+)
	M ∼ 5.5	4.2	(−)	0	4^(+)
12. Social issues	Livelihood losses	88	(+)	1	1^(−)
	Agriculture losses	71	(+)	0.6	3^(+)
	Horticulture losses	81	(+)	0.83	2^(+)
	Property losses	45	(+)	0	4^(+)

Table 1.

Vulnerability assessment index for the lower zone.

AV = actual Value NV = normalized value; MCT = main central Thrust; LULC = Land use land cover.

4.2 Slope aspect

The study region serve high portion of rocky land surface (98.7%) and sandy loam soil serve only 0.93%. The lowest portion was found under the sandy loam types of soil (0.2%). The southern aspect of slope had received high sensitivity (14.2) with positive vulnerability (1). The other aspect of the region such as east (0.75), South east (0.84), west (0.53) have high vulnerability. The northeast (0.31), east (0.75), south and west (0.53) have low vulnerability which evident the negative relationship. Pooh village, there were a large number of landslides occurred during summer-monsoon season due to snow melting. Soil creep, rock slide and rock fall were the common features [12].

4.3 Lithology

The rates of change of erosion, landslides are very much controlled by the lithology. The limestone topography is more vulnerable for construction with humid climatic condition. But it becomes more resist in the climate of arid to semi-arid [13]. The lithology consists the ortho quartzite, basic volcanic & limestone /dolomite was very sensitive (4.39) and highly affected which has high vulnerability (1) with positive vulnerability relationship (1). The high vulnerability was found under the topography namely (Pg3o) Boulder conglomerate sandstone, shale, clay (0.67), (Pt₂₃) Slate Phyllite, quartzite, gray shale (0.38), (Y) Granite & granitoid (0.91). The low vulnerability was recorded under the lithology types of (OC) Limestone, Siltstone (3.1) and (Pt3e) Greenish gray sandstone (1.79).

4.4 Soil texture

The soil texture of the region was classified in to coarse; fine, medium, rocky/bad land on the basis of secondary map and direct field observations. The soil of region was dry and consisting very fine particles and considered as the fine texture of soil. Such types of soil were found in the area like Tapri, Shongtong, Recongpeo, Powari, Kyari, Khwani, Pangi, Poh, Dakhu and Khab. The soil erosion is very common during the summer season (March to June). The rocky surface of the region was highly affected by the anthropogenic activities (blasting & tunneling) [14]. The Fine texture of the soil has high sensitivity (6.71) through the soil erosion and landslides. Fine texture (1.71) and Rocky/bad land (13.41) surface had high sensitivity and positive vulnerability score. However the medium texture (0.39) and coarse texture had less impact (3.6) with low vulnerability. Due to road and dam constructions, the rocky surface was highly influenced under the anthropogenic activities. Road cutting, tunneling and blasting were the major causes of the loss of physical landscape.

4.5 Land use and land cover (LULC)

Mass movement was largely influenced by land use and land cover change in the valley. More than 66.79 km²areas was damaged due to landslides and construction activities, which include 10.8 km² agriculture, 10.2 km² forest, 14.1 km² wasteland, 14.6 km² grassland, 1.46 km² scrubland and 2.23 km² water bodies. The land degradation was high due to blasting, road widening and construction activities of hydropower. Settlements in an area of about 0.21 km² were damaged. The highest adversely affected area of 53.63 km² under LULC was affected in river valley. The highest adversely impacted area was occurred in case of wasteland (14.2 km²). Snow covered area was found scarcely affected. The highest vulnerability was found under the grass/grazing land 14.6 (1), the waste land of valley was highly affected 2 (0.96) under the landslides and soil erosion. The scrubland had damaged area (1.46) 0.93 under the landslides and soil erosion but rarely affected with anthropogenic activities. Forest cover area of region had positive relationship with soil erosion and landslides [2]. The vulnerability score of the forest cover was 0.69 and ranked as 5. The agriculture area of the region was affected due to the landslides and soil erosion. The most of losses were found because of constructive activities. The water bodies (0.14), snow glacier areas (8) were also adversely affected.

4.6 Slope profile

Slope profile study was done on the basis of field survey. Free face segment and summital convexity of hill slopes were very common in the valleys of the Satluj valley, which cause high degradation of slopes and is also known as waxing slope. The Urni landslide slope was also affected due to the anthropogenic activities. Tanglling, Powari and Shongtong HEP area was also affected due to the construction activities.

The field surveys also made clear that most of the debris falls were found on this segment of slope. These types of slopes were found in the Satluj valley. A concave element of slope was very commonly found in lower portion of the Satluj valley. The free face, rectilinear section and summital convexity were affected mainly due to the construction activities. Summital convexity (3.1), Basal concavity (3.6) had high sensitivity which indicates the positive relation of impact and vulnerability. The free face (1.7) and rectilinear (2.5) were less affected by physical loss.

4.7 Relative relief (R_R)

GIS analysis indicated the high value of relative relief (R_R 5222 m). had the low vulnerability and indicates the negative value (0.24). Dissection index (DI = R_R/A_R) showed high value (0.64–0.93) indicating high vulnerability in terms of soil erosion, mass movement and flood in the Satluj valley [15]. The relative relief namely R_R 4011 m had high sensitivity which indicates the high vulnerability (7.4).

4.8 River morphological aspect

The river slope gradient was varies from 11.50 to 15.70 and the average channel slope gradient was 13.50. The high average slope gradient was one of the favorable conditions for the development of hydroelectric projects in this valley. The high slope gradient region had the highest number of allocated hydropower projects. High channel slope gradient is directly proposal to the high potential energy (Pe) and high kinetic energy (Ke). The high slope gradient region had the high sensitivity and vulnerability (1). The study region had the low drainage density (Dd = 0.32) and low texture of river. Higher the drainage density indicated the high surface runoff and high yield to soil erosion. But here low drainage texture and low value of bifurcation ratio (Rb 1.84) indicates that river channel had not strongly controlled by the parent rock. Because of that reason the region more vulnerable during the time of flash flood. The climate condition, vegetation covered, anthropogenic activities types factors had adverse impact on the river morphology. The valley was characteristic for a trellised drainage pattern. Here, stream pattern was turned towards the regional slope and geological structures like folds and faults.

4.9 Social issues

Livelihood, agriculture, horticulture and properties losses were major elements of social environment. The social issues were very sensitive in this region. The region has complex topography with adverse climatic condition. The agriculture and horticulture are main livelihood option in this region. The total geographic area was 624,000 hectare out of which 7.07 was cultivable land, 124,000 hectare was non agriculture and barren and uncultivable land was only 131.1200 hectare. The livelihood losses were commonly observed in the affected area under the constructed hydroelectric project [16]. The high sensitivity was found under the livelihood losses (1) and horticulture losses (0.83). The agriculture (0.6) and property losses (45) were ranked 3 and 4 respectively.

4.10 Landslide

The economic as well as loss of life due to landslides were considerably increased in the last century, and most of the landslides are due to global climate change, such as, El Niño and human activities [17]. Topographic variance (434–6448 m asml) influences precipitation pattern in the study region. Annual isohyets varied from 100 to 1400 mm. Rainfall decreased in this valley from the lesser to the Greater Himalaya. The lower part of valley of the Satluj valley falls under the sub-humid temperate to humid region. Here, rainfall pattern varied from 300 mm to 1400 mm. Total 111 landslides were identified out of which 21 were large (>0.198 km²) and 90 were small (<0.198 km²). The maximum numbers of landslides were noticed along the River Satluj and their validation was done through the GPS survey. Steep slopes, high relief, number of structural discontinuities and underlying geology were combined with anthropogenic activities which decrease the stability of slope [18]. Steep and vertical slopes have high degree of landslides. The highest affected area was found under the micro landslides, because these landslides were more in number. The constructed area of region was adversely affected under the anthropogenic activities which were ranked as 1. The area was affected under the large landslides ranked as 2 (Table 1).

4.11 Flood

Satluj valley is known for its divesting flood events the flood incidences were observed in 1993, 1995, 1997, 2000, 2005, 2007 and 2013. During the flash flood the water level was raise up to 15 ∼ 20 m from the normal water level and its water label go up to 10–12 time more than the normal water discharge. The main river of region consist the 4 type’s stream; the first order (0) and second order stream (0.5) had the negative relation between flood and sensitivity. The 3 orders (0.75) and 4 order streams (1) had the positive relationship of sensitivity [19]. It was made clear from the GIS study that affected area 139 km² due to flood was found and out of which 80 km² was found under high vulnerability.

4.12 Earthquake occurrences

The earthquakes occurrences were commonly observed in the study region. The 3.2 to 6.5 tremors of earthquakes were recorded in region. These earthquakes were sufficient to generate the landslides at micro and macro level. The study region have number of faults and MCT (main central thrust, separates the Greater Himalaya from the Lesser Himalaya) and faults were found in the lower zone where the Main Boundary Fault (MBF) passing through the region. However, sediment flux might be affected largely due to stronger earthquakes with greater magnitudes of MS > 7 [20]. Despite, seismically active mountain belts have shown link between earthquakes, landslides and fluvial sediment transport. The earthquakes sensitivity was analyzed on four deciding factors namely faults, MCT/Thrust, Magnitudes 6.1 and 5.5. The highest degraded areas were found near the tectonically sensitive area (faults & thrust). High vulnerability relationship were found under the all elements namely faults (1), MCT/Thrusts (8.3), 6.1(0.58) and 5.5 (0). The geological elements region was highly ranked under the vulnerability (1).

4.13 The peoples’ perception survey

The peoples’ perception survey was conducted in high altitude villages of valley like Apka (2454 m, Punag (1930 m) Tapri (2385 m) Agade (1599 m),Punasa (1791 m) and Surga (1591 m) (Figure 3). 67 households’ survey samples were collected from the field. A structured questionnaire was designed and the direct survey was conducted by using the random sampling. The impacts of hydroelectric projects in the valley and the resultant socio-economic benefits of the communities were taken into account. About 46% of the total interviewees were perceived that the developmental footprints in terms of infrastructure, road, and colonies were visible in the valley. The local communities expressed their dissatisfaction in terms of their livelihood generation and inadequate compensation in lieu of their land loss. In the study area, 76% of the total interviewed individuals were perceived that agricultural loss, horticulture loss, drying up of springs and natural water sources, and impact of blasting on the individual houses were observed high in the valleys. People perceived that the earthquake incidences also increased in recent times and unscientific constructions, indiscriminate debris, dumping of muck along with the river banks result in many disorders, high adverse impacts in downslope regions. People were also believed that hydropower’s project has bad impacts on their agriculture, horticulture, livelihood and social. People suggested that hydropower development should be controlled manner and should focus on tourism development as a sustainable livelihood option. Respondents also told that the tourism business also affected with hazards incidences if year is free from hazards incidences then tourist’s number was high. But road were severely affected with the hazards like landslides, flood, anthropogenic activities (haphazard development of hydropower, blasting & tunneling).

Figure 3.

Survey villages location in upper Satluj Valley, district Kinnaur.

4.14 Consultation meetings with the stakeholders

Regional Centre of Himachal Pradesh, Mohal-Kullu, Himachal Pradesh, India [3]. On the Figure 4.

Figure 4.

A. Interaction with local people B. leakage of water from rock cracks C. degraded bank of Satluj River D. wide cross-section and gentle slope gradient of river channel E. landside of Sudharang Dakhu F. SEA meeting with government and local stakeholders G. slope cutting near Shongtong H. penstock of small hydroelectric project, near Tapri I. dry river bed of Satluj River.

The three strategic environmental assessment meetings were held in the deputy commissioner’s office in Kinnaur, Rekong Peo on 26th Novem26th November 2014, 7th December 2015, and 23rd December 2016. The objective of these meetings is to interact with the local people and to know the environmental impacts on the social and physical environment. The project proponents, non-governmental organizations (NGOs), and local representatives were the main participants in these meetings. 83% of the respondents believed that their agricultural land was highly affected by the construction activities of hydropower. Local people admitted that the physical loss of landscape was high in the region. The local communities were against the large hydroelectric projects (>25 MW) construction in this valley.

The villagers of Sudharang Dakhu village explained that extensive tunneling and blasting were the major responsible causes for the continuous landslide and other physical loss. The people of the Satluj valley believed that the mitigation measure is very poor in and around hydroelectric projects. During the meeting, the participants replied that there is a need to recheck the inter distance of the hydroelectric project in the valley. The excessive development of hydroelectric projects in the signal valley should follow the inter distance. They suggested that there should be a fixed minimum radius between the two projects. 87.88% of participants suggested that there should be a fixed radius of 7 km between the two large projects, 87.88% suggested a 5 km radius between two small projects, and 81.82% and 3 km radius between two small projects. During these meetings and workshops, issues pertaining physical and social losses were discussed to a large extent. The stakeholders suggested that development of HEPs need to be controlled rationally so as to make them eco-friendly and sustainable (Figure 5).

Figure 5.

Word life sanctuary within the buffer of 10 km.

The national park and wildlife sanctuary is an Eco-sensitive zone and within a radius of 10 km, all construction and anthropogenic activities are not permitted. This guideline was issued on 09.02.2011 regarding ‘bird sanctuary’ as a ‘protected area’ under Section 18 and 26 (A) of the Wildlife (Protection Act, 1972) [21, 22, 23, 24, 25]. Many wildlife sanctuaries and national parks are falls within the buffer of 10 km and this criterion was exploited by the project developer. Even all hydroelectric projects were not following any aerial distance criteria from one project to another (Figures 6 and 7).

Figure 6.

Unequal distribution of hydroelectric project in Satluj Valley, district Kinnaur, Himachal Pradesh.

Figure 7.

The geocentric mean validate the high concentration of hydroelectric projects in particular area of valley.

In this valley, there are different types of hydroelectric projects such as commissioned, under construction, and proposed projects. The 11 projects overlapped the area of other projects and not followed any inter-distance method. In the area of a high density of hydroelectric projects number area, the maximum physical losses and physical losses were recorded. The equidistance analysis of these hydroelectric projects was done and the geocentric mean was measured. The spatial analysis indicates that the maximum concentration of hydroelectric projects was found in the lower segments of the lower valley (Figure 8). It was evident from the field survey that the maximum concentration of HEPs in a particular area was caused due to the physical degradation (Figure 9).

Figure 8.

Overlapping of hydroelectric projects.

Figure 9.

Suggestive strategy to avoid the physical loss in study area.

If we reduce the number of hydroelectric projects and develop the minimum equidistance criteria for the upcoming projects, the loss to physical landscape and resentment among the public regarding compensation and others would be minimum. The equidistance strategy can be implement in the River valley to avoid the physical loss the same model we can apply aerial inter distance between the projects where 7 km radius for large hydroelectric project 25 MW, 5 km for medium (5-25 MW) and 3 km should be suggested for small projects in mountain environment [3, 7]. Reservoirs / dams and powerhouse sites can be considered for a midpoint of equidistance buffer; however this can be depends on the nature of hydropower projects.

5. Conclusion

Strategic planning was done for avoiding the physical losses of valley. The physical losses were recorded in the valley. The indicators based analysis of the valley revealed that valley had the high sensitivity and vulnerability (7.5). The hydropower development was one of the important activities which responsible for the many environmental problems. It was evident from the GIS and remote sensing analysis that maximum losses were observed in the main river valley and near to the constructive activities. The anthropogenic activities were exorbitant the physical condition of the valley. The maximum numbers of landslides incidences were recorded near the constructive activities related to the hydro powers and roads. The incidences of slope failures, soil erosion, poor soil textures, low green cover (8%), high relative relief, floods, landslides, high anthropogenic activities indicates high vulnerability (7.5). The adverse impacts of hydropower projects were high as comparison to the positive impacts. The vulnerability of 753.41 km² area was identified under the physical loss which is very high in the valley and may exacerbate with the day-to-day increasing anthropogenic pressures. This was evident from the five interaction meeting that people of the study area were not satisfied with these developmental activities and they want control on the development activities. The brain storming meeting result revealed that there is need of equidistance between two hydroelectric projects. The agriculture losses, drying up of natural water resources, loss of horticulture land, muck deposition impact on river morphology, blasting impact on the people houses were noticed under the adverse impacts of hydroelectric projects.

The complex geophysical condition of the region is also responsible for the landslide incidences but the haphazardous developments of the hydroelectric projects aggravated the physical loss of the region. However, the maximum losses were found in and surrounding large hydroelectric projects and small hydroelectric projects region had the fewer incidences of physical degradation. To reduce the incidences of landslides there is a need to implement the fixed aerial equidistance from one project to the next project. However, there is a need to control hydropower development in the river valley in a sustainable way. If we succeed to implement the equidistance buffer between two projects then we succeed to control the environmental loss in and surrounding hydroelectric projects. This strategy would be beneficial in the mountain region to control the incidences of soil erosion, mass movement, and landslides.

Acknowledgments

The authors are heartily thankful to different stakeholders (local communities, project authorities and local government) for their constant support and cooperation during field study.