AMERICAN-EURASIAN JOURNAL OF SUSTAINABLE AGRICULTURE ISSN: 1995-0748, EISSN: 1998-1074 2017, volume(11), issue(5): pages (59-67) Published Online in http://www.aensiweb.com/AEJSA/

Hydroecological risk assessment of small hydropower plants operation in Armenia (Based on example of Vardenis,

Karchaghbyur and Arpa rivers)

1Gor Gevorgyan, 2Armine Hayrapetyan, 3Armine Mamyan, 4Bardukh Gabrielyan

1Gor Gevorgyan, Senior scientific worker, Department of Hydroecology, Institute of Hydroecology and Ichthyology of SCZHE of NAS RA, Yerevan, Armenia, 2Armine Hayrapetyan, Senior scientific worker, Department of Hydrobiology, Institute of Hydroecology and Ichthyology of SCZHE of NAS RA, Yerevan, Armenia, 3Armine Mamyan, Scientific worker, Department of Hydroecology, Institute of Hydroecology and Ichthyology of SCZHE of NAS RA, Yerevan, 4Bardukh Gabrielyan, Director, Scientific Center of Zoology and Hydroecology of NAS RA, Yerevan, Armenia,

Received 12 July 2017; Accepted 30 September 2017; Published Online 7 October 2017

Address For Correspondence: Gor Gevorgyan, Department of Hydroecology, Institute of Hydroecology and Ichthyology of SCZHE of NAS RA, 0014 Yerevan, Armenia, E-mail: [email protected]

Copyright © 2017 by authors and American-Eurasian Network for Scientific Information. This work is licensed under the Creative Commons Attribution International License (CC BY). http://creativecommons.org/licenses/by/4.0/

ABSTRACT

Investigating the mechanisms behind the hydroecological effects of small hydropower plants (SHPs) operation is urgently required since increasing growth in the hydropower sector has become a serious threat to river ecosystems. The aim of the present study was to investigate and assess the hydrobiological and –chemical risks of SHPs operation in Armenia. As model objects, we investigated the Vardenis, Karchaghbyur and Arpa rivers in Armenia. Observations showed that in the Vardenis river site located downstream from the SHP (where the water was taken in the SHP pipe), the aquatic ecosystem within a distance of a few kilometers was destroyed due to the intake of almost all the quantity of the water by the SHP, and the fish passage system of the SHP had formal nature. If the fish passage system in the SHP located on the Vardenis river had formal nature, then the SHP operating on the Karchaghbyur river didn’t even have a fishway, which caused an obstacle for the migration and natural reproduction of Lake Sevan endemic fish species. Due to the operation of the SHP on the Karchaghbyur river, the decreased river velocity and the increased water temperature in the site located downstream from the SHP caused changes in planktonic organisms composition: increased growth of zooplankton led to the decreased quantitative and qualitative parameters of phytoplankton in most cases. In other case, the quantitative and qualitative parameters of phytoplankton in the site located downstream from the SHP increased, because in this case, the decreased river velocity was the main driver of phytoplankton growth. Hydrochemical study in the Arpa river showed the increased level of mineral nitrogen and salts in the observation sites located downstream from all 3 SHPs operating on the Arpa river, which was probably due to lower dilution rate caused by water intake by the SHPs. Based on the example of the Vardenis, Karchaghbyur and Arpa rivers, it’s possible to state that SHPs operation on the Armenian river ecosystems leads to unpredicted changes in the quantitative and qualitative compositions of hydrobiological communities such as phyto– and zooplankton, the absence of environmental flow management and fish passage systems causes the destruction of river sections and blocks the fish migration preventing their natural reproduction, decreased river velocity and discharge caused by SHPs operation results in anthropogenic pollution (mineral nitrogen and salts) intensification due to lower dilution rate in river sections.

KEY WORDS Armenia, rivers, small hydropower plants, effects, hydrobiological communities, hydrochemical parameters.

INTRODUCTION

Today, energy consumed all over the world comprises 34.5% liquids, 26% coal, 23.5% natural gas, 5.5% nuclear and 10.5% renewable [1, 2]. The increasing demand of energy in many countries, especially in

AMERICAN-EURASIAN JOURNAL OF SUSTAINABLE AGRICULTURE. 11(5) September 2017, Pages: 59-67 Gor Gevorgyan et al, 2017 60 developing countries has led to the acceleration of energetic sphere development rate. In recent years, increased growth in the hydropower sector has been observed. The renewable energy technologies emerged as the most important solution to the environmental problems caused by the conventional source of energy. Hydropower is the most traditional clean renewable energy source and the most important for electrical power production worldwide. The energy source of hydropower is running water from rivers or streams. In run-of-river small hydropower schemes, part of the flow of the stream is diverted through a pipe, which takes the water to a penstock, where it is forced to fall into hydro-turbines situated in the powerhouse. These turbines convert water pressure into mechanical shaft power, which can be used to drive an electricity generator. Afterwards the flow comes back to the stream [3]. International Energy Agency notes that small hydropower plant (SHP) tends to have a relatively small and localized impact on the environment. However, a conflict between human demand and ecological water requirement on aquatic ecosystems may increase [4]. Small hydropower is claimed to cause negligible effects on ecosystems, although some environmental values are threatened [3]. Despite their doubtless advantages, SHPs can lead to several environmental risks such as lower water quality, ecosystem destruction and biodiversity loss [5]. Giving priority to the development of economic sphere, the possible environmental effects of SHPs have been ignored or little attention has been paid. Some of environmental impacts of SHPs start as soon the construction phase [6]. These impacts will of course vary from case to case [7]. SHPs affecting the natural flow of rivers can change stream physicochemical characteristics and alter the quantity and quality of aquatic habitat, with cascading impacts on stream biota [6, 8]. These energetic constructions not only kill fish but also may block their migration in a riverbed. In the literature, there are some hydrological, hydrophysical, –chemical, –biological, –ecological and methodological studies considering risk analysis for SHPs, however such investigations are very limited [2–10]. The ecological impacts of these hydropower constructions are poorly understood and are not being adequately studied [8]. The construction of SHPs in the Republic of Armenia (RA) is considered as a leading direction of the development of renewable energy sector [11, 12]. Increasing number of SHPs on Armenian rivers is one of the most important environmental issues in the country. In Armenia, there isn’t a methodology for the complex evaluation of SHPs impact on ecosystems. Rivers are only considered as potential hydropower resources without regard to their impact on the environment and communities. If more than 20% of river length is piped, the river ecosystem will become stressed [11]. This norm isn’t taken into consideration in case of many Armenian rivers serving as a renewable energy source [11, 13]. SHPs in Armenia don’t have environmental flow management system. Incorrect project hydroeconomic estimates are other serious issues in relation to aquatic ecosystem protection [13]. Due to the operation of SHPs, 16 river ecosystems are currently in critical situation, and 3 rivers – in disastrous situation [11]. From the point of view of SHPs environmental effects, the Lake Sevan catchment basin situated in the eastern part of the Republic of Armenia (Gegharkunik Province) is considered one of the most vulnerable areas. Being a habitat for endemic fish species such as Khramicarp-Capoeta capoeta sevangi (Filippi), Sevan Barbel- Barbus goktschaicus (Kessler), and Sevan Trout-Salmo ischchan (Kessler), it has been affected by SHPs [14, 15]. Fish passways in Armenia are projected under the existing standards, which, as a matter of fact, are mainly developed for large rivers in plains [13]. However, not only in Lake Sevan catchment basin but also in the whole country, rivers are small and mountainous. All of this may cause serious hydroecological and –biological problems in the Lake Sevan catchment basin. The Arpa river catchment basin situated in the southeastern part of Armenia is another vulnerable area as it is overloaded with SHPs. More than 15 SHPs are operating on the Arpa river and its tributaries [16]. As of July 1, 2015, Public Services Regulatory Commission of the RA gave a license for constructing 8 additional SHPs on the Arpa river and its tributaries the construction and operation of which will promote increased load on the river ecosystems [12]. The Arpa river (total length – 126 km, in Armenia – 90 km) originated from south-east of Vardenis mountain is one of the major tributaries of the transboundary Araks river in the territory of Armenia [17]. It is one of the biggest rivers feeding Lake Sevan. As of December 31, 2014, water volume of 130.23 mln. m3 entered into Lake Sevan through Arpa-Sevan water channel [12]. Taking into consideration the strategic importance of the Arpa river as a transboundary river and an additional water supply for Lake Sevan, it’s very important to implement a hydroecological investigation in the river affected by SHPs. For conserving water and hydrobiological resources, the investigation of the ecological aspect of SHPs operation in Armenia is urgently required. The aim of the present study was to investigate and assess the hydrobiological and –chemical risks of SHPs operation in Armenia.

MATERIAL AND METHODS

As model objects, we investigated the Vardenis and Karchaghbyur rivers in the Lake Sevan watershed basin and the Arpa river. For assessing the hydrobiological and –chemical impacts of SHPs on the river ecosystems, phyto–, zooplankton and fish studies in the Karchagbyur and Vardenis rivers and organic (BOD5), nutrient 61

(mineral nitrogen and phosphorus) and salt (EC) pollution investigations in the Arpa river were carried out. Observations, measurements and sampling were done in the river sites situated upstream and downstream (where the certain volume of the water was taken in the SHP pipes) from the SHPs located on the rivers in different seasons of 2013, 2014 and 2016 (Table 1).

Table 1: Coordinates of rivers investigated site.

Sampling site number N/Lat E/Long River site location 1 40°05'32.3" 45°27'49.3" Vardenis river site located upstream from the SHP 2 40°05'35.3" 45°27'57.0" Vardenis river site located downstream from the SHP 3 40°09'45.1" 45°35'05.7" Karchaghbyur river site located upstream from the SHP 4 40°10'27.4" 45°34'58.4" Karchaghbyur river site located downstream from the SHP 5 39°52'17.4" 45°42'54.9" Arpa river site located upstream from the SHP-1 6 39°52'06.4" 45°42'38.9" Arpa river site located downstream from the SHP-1 7 39°41'33.0" 45°27'06.6" Arpa river site located upstream from the SHP-2 8 39°42'54.4" 45°24'53.5" Arpa river site located downstream from the SHP-2 9 39°43'55.8" 45°12'02.8" Arpa river site located upstream from the SHP-3 10 39°43'49.4" 45°11'50.3" Arpa river site located downstream from the SHP-3

For the calculation of river velocity in the investigation sites, a bobber was vented from the selected point of the rivers, and a stopwatch was started. The watch was stopped after the bobber passed the selected distance. The river velocity was determined by dividing the selected distance by the time recorded on the watch. River discharge in the investigation sites was measured by the following formula:

Q = ω × V (1)

... where Q is the river discharge, ω is the cross-sectional area of the river at the point of flow measurement, V is the velocity at which the water travels across that section. The cross-sectional area of the river was calculated by multiplying the water level by the river width. River water level was measured by a water level meter. As only one measurement of the water level was taken, therefore an approximation in calculating the river cross section was considered. All the hydrological parameters were measured at the centre of river width. For the phytoplankton analysis, a 1-liter water sample taken from each site was preserved with 40% formaldehyde solution (0.4% final concentration) and stored in a dark place. Further study was carried out under laboratory conditions. The fixed phytoplankton samples were settled in a dark space for 10–12 days, and then the volume of the experimental samples was decreased from 1000 ml to 100 ml by a siphon (50 µm). Repeating the same process for the second time, the volume of the experimental samples was reduced to 10 ml [18]. The qualitative and quantitative analyses of phytoplankton were executed under a microscope (XSZ-107BN-C) using Nageotte chamber. For the zooplankton analysis, water samples were taken with a bucket, and they were filtered through a plankton net (50 µm) and fixed with formalin solution (4–5% final concentration). The further processing of the samples was carried out by the standard methods accepted in hydrobiology [19–21]. The qualitative and quantitative analyses of zooplankton were done under a microscope (XSZ-107BN-C) using Bogorov camera. Fish hunting was implemented by a fishing net. They were fixed with 4% formaldehyde solution for further taxonomic identification under laboratory conditions. The qualitative analysis of fish was executed by using different types of microscopes (MC-2-Zoom Digital, XSZ-107BN-C). Taxonomic groups of phyto–, zooplankton and fish were identified by using the keys/determinants of freshwater systems [22–28]. Water samples for BOD5 and nutrient (nitrate, nitrite, ammonium and phosphate ions) analyses were taken with cleaned polythene bottles (1 liter). In the laboratory, BOD5 values were determined according to the standard method [29]. Initial dissolved oxygen (DO) and residual DO after five days incubation at 20°C were measured by the electrochemical probe method by using a water oximeter (HI98193) [30]. The contents of nitrate (cadmium reduction method), nitrite (diazotization method), ammonium (Nessler method) and phosphate (ascorbic acid method) ions were determined by a multi-parameter photometer (HI83200) [31]. All the glassware and sampling bottles were pre-washed in acid before use. Water temperature (T) and electrical conductivity (EC) measurements were conducted in field conditions. T was determined using a digital thermometer (ST9265), and EC using multi-parameter tester (HI98129).

RESULTS AND DISSCUSION

During the investigation period, the zooplankton quantitative (abundance – 15-152 individuum/m3, biomass – 0.023-0.300 mg/m3) and qualitative (species number – 1) parameters registered in the Vardenis river site 62 located upstream from the SHP (No. 1) were quite low, and no one animal was recorded in December 2013. Comparatively high quantitative and qualitative values of planktonic algae (abundance – 239-1508 cell/ml, biomass – 1.0294-6.4550 g/m3, species number – 8-20) were registered in this observation site. Only fish species hooked from this site was Salmo trutta fario (Linnaeus 1758). In the Vardenis river site located downstream from the SHP (No. 2), the aquatic ecosystem within a distance of a few kilometers was destroyed due to the intake of almost all the quantity of the water by the SHP (Fig. 1). Although there was a fish passway in the Vardenis river SHP, however it had formal nature, and the SHP didn’t ensure fish migration along the river. Even inadequate water released to and the inadequate design of fishways or fish ladders may cause a problem [2, 5]. Investigations conducted by Kucukali S. have shown that in the Tefen SHP located on the Filyos river (Turkey), the fish passage system doesn’t correspond to a standard fish-passage type and blocks fish migration, endangering their presence in the region [5]. It has been reported that even the most appropriate fish passages in France create at least some delay in migration, and the plant turbines cause fish deaths. According to Baskaya S. et al, in Turkey, control over environmental flow is a highly serious environmental problem in plants already in the production phase. There is no strict control over the amount of environmental flow. Even the required 10% environmental flow, which is considered insufficient by the majority of public, sometimes isn’t released into riverbeds for several days [2]. During the investigation period, the quantitative and qualitative parameters of zooplankton according to the Karchaghbyur river sites located upstream (No. 3) and downstream (No. 4) from the SHP increased, because the water (river velocity) and thermal regimes in the site located downstream from the SHP were more favorable for the growth of zooplanktonic organisms (Fig. 2, Table 2). The decreased river velocity and the increased water temperature accelerated the growth rates of zooplankton [32–35]. In the Karchaghbyur river site located downstream from the SHP, a decrease in the river velocity and an increase in the water temperature were mainly due to the intake of certain volume of water by the SHP and because of the reservation of water before the intake (Table 2). The investigations conducted in Fall 2013 and Winter 2013–2014 showed that the quantitative and qualitative parameters of phytoplanktonic organisms according to the Karchaghbyur river observation sites located upstream and downstream from the SHP decreased, which is explained by the pressure of zooplanktonic organisms, which are the main phytoplankton grazers (Figs. 2 and 3) [36, 37]. In Spring 2014, the quantitative and qualitative parameters of phytoplankton according to the observation sites located upstream and downstream from the SHP increased (Fig. 3). In this case, the decreased river velocity was the main driver of the increased growth of phytoplankton (Table 2). It’s known that phytoplankton as well as zooplankton grow well in the conditions of low water velocity [32, 33, 35]. It is necessary to mention that an increase in the phytoplankton quantitative parameters was slightly expressed, which is explained by the pressure of the main phytoplankton grazers – zooplanktonic organisms (Figs. 2, 3a,b) [36, 37]. It’s worthy to note that investigations on the hydrobiological impacts of SHPs operation are mainly devoted to fish and benthic communities [2–6, 8– 10]. Nevertheless, plankton is very much sensitive to hydrological parameters and can undergo significant changes due to SHPs operation [17, 38–40]. From this point of view, the obtained results are very important and valuable.

Fig. 1: Vardenis river site located downstream from the SHP.

63

a) b) Upstream from SHP Downstream from SHP Upstream from SHP Downstream from SHP 9

1000 ) 3 900 8

800 7

) 700 3 6 600 5

individuum/m 500 4 400 3 300 2 200 (mg/m Biomass 1

100 Abundance ( Abundance 0 0 Oct 2013 Nov 2013 Dec 2013 Jan 2014 Feb 2014 May 2014 Oct 2013 Nov 2013 Dec 2013 Jan 2014 Feb2014 May 2014

c) Upstream from SHP Downstream from SHP 7

6

5 4 3

2 Species number Species 1 0 Oct 2013 Nov 2013 Dec 2013 Jan 2014 Feb 2014 May 2014

Fig. 2: Quantitative and qualitative parameters of zooplankton in the Karchaghbyur river.

Table 2: Hydrological and thermal regimes in the Karchaghbyur river.

Sampling site Oct 2013 Nov 2013 Dec 2013 Jan 2014 Feb 2014 May 2014 number River velocity (m/s) 3 0.75 0.73 0.69 0.62 0.66 1.03 4 0.50 0.43 0.38 0.37 0.43 0.83 Water temperature (°C) 3 8.0 6.5 2.0 0.9 1.8 9.5 4 10.0 9.0 4.5 2.8 5.9 11.0

a) b) Upstream from SHP Downstream from SHP Upstream from SHP Downstream from SHP

2500 10

)

2000 3 8

1500 6

1000 4

iomass (g/m iomass B

Abundance (cell/ml) Abundance 500 2

0 0 Oct 2013 Nov 2013 Dec 2013 Jan 2014 Feb 2014 May 2014 Oct 2013 Nov 2013 Dec 2013 Jan 2014 Feb 2014 May 2014

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c) Upstream from SHP Downstream from SHP 35

30

25 20 15

10 Species number Species 5 0 Oct 2013 Nov 2013 Dec 2013 Jan 2014 Feb 2014 May 2014

Fig. 3: Quantitative and qualitative parameters of phytoplankton in the Karchaghbyur river.

During the investigation period, no one fish species was registered in the investigated sites of the Karchaghbyur river. The races Salmo ischchan gegarkuni (Kessler) and Salmo ischchan aestivalis (Fortunatov) of the Lake Sevan endemic fish species Salmo ischchan spawn in the lake tributaries, where the sources are considered as the most favorable places for spawning. Salmo ischchan gegarkuni (Kessler) spawns in Fall and Winter, and Salmo ischchan aestivalis (Fortunatov) spawns in Spring [14]. In the spawning period of Salmo ischchan gegarkuni (Kessler) and Salmo ischchan aestivalis (Fortunatov), no one specimen of these fish species was registered in the studied observation sites of the Karchaghbyur river, which allows to conclude that the SHP located on the river prevented the migration of the fish along the river. According to the laws of Armenia, it’s essential to ensure fish movement. To this end, the construction of fishways for fish migration is essential. However, our observations showed that there wasn’t a fish passway in the Karchaghbyur river SHP, and the dam height of more than 1 meter was a real obstacle for ensuring the free movement and natural reproduction of endemic fish species (Fig. 4). If fish passways in many SHPs located on Armenian rivers don’t perform their main aim – to bridge fish species inhabiting in different sections of a river for their free movement and the preservation and natural reproduction of fish reserves, then the Karchaghbyur river SHP didn’t even have a fish passage system [13].

Fig. 4: SHP operating on the Karchaghbyur river.

For assessing hydrochemical effects of SHPs operation, organic (BOD5), nutrient (mineral nitrogen and phosphorus) and salt (EC) pollution investigations in the Arpa river were carried out. The results of the hydrochemical study showed that mineral nitrogen and salt pollution degree in the observation sites located downstream from all 3 SHPs operating on the Arpa river (Nos. 6, 8, 10) increased, which was probably conditioned by an elevated anthropogenic nitrogen and salt pollution level in the conditions of a decrease in the river velocity and discharge (Tables 3–5). The pollution was intensified due to lower dilution rate in the river observation sites located downstream from the SHPs. In case of organic matter content, this regularity was only registered in the observation site No. 8 affected by the SHP-2 (Table 4). In other cases, no obvious regularity in changes in the concentrations of chemicals was observed (Tables 3 and 4).

65

Table 3: Nutrient regime in the Arpa river.

Sampling site May 2016 July 2016 Nov 2016 number Mineral nitrogen (mg N/l) 5 0.60 0.42 0.61 6 0.69 0.85 0.70 7 0.85 1.10 1.32 8 0.87 1.97 2.65 9 0.78 2.40 2.51 10 1.02 2.60 2.60 Mineral phosphorus (phosphates) (mg/l) 5 0.17 0.21 0.14 6 0.19 0.09 0.10 7 0.09 0.18 0.21 8 0.11 0.09 0.55 9 0.21 0.67 0.12 10 0.13 0.22 0.15

Table 4: EC and BOD5 values in the Arpa river.

Sampling site May 2016 July 2016 Nov 2016 number EC (µS/cm) 5 58 70 68 6 64 78 76 7 134 290 280 8 254 622 912 9 156 418 350 10 182 520 376

BOD5 (mgO/l) 5 1.9 1.8 2.1 6 2.1 1.9 2.0 7 2.2 2.0 3.4 8 2.2 2.6 3.7 9 2.0 2.2 3.3 10 2.4 2.0 3.0

Table 5: Hydrological regime in the Arpa river.

Sampling site May 2016 July 2016 Nov 2016 number River velocity (m/s) 5 1.90 1.25 0.84 6 0.80 0.28 0.43 7 1.80 0.98 0.76 8 1.20 0.40 0.47 9 1.14 1.05 0.91 10 0.73 0.36 0.59 River discharge (m3/s) 5 13.20 5.53 3.32 6 8.10 0.47 0.34 7 19.10 9.18 5.70 8 10.86 1.12 0.63 9 22.80 14.36 12.12 10 13.14 6.75 7.26

Conclusion: Observations showed that the Vardenis river section within a distance of a few kilometers was destroyed due to the intake of almost all the quantity of the water by the SHP, and the fish passage system of the SHP had formal nature. The SHP operating on the Karchaghbyur river didn’t even have a fishway and caused an obstacle for the migration and natural reproduction of endemic fish species. Due to the operation of the SHP on the Karchaghbyur river, the decreased river velocity and the increased water temperature in the site located downstream from the SHP caused changes in plankton community: increased growth of zooplankton led to the decreased quantitative and qualitative parameters of phytoplankton in most cases. In other case, the quantitative and qualitative parameters of phytoplankton according to the observation sites located upstream and downstream from the SHP increased, because the decreased river velocity was the main driver of phytoplankton 66 growth. Hydrochemical study in the Arpa river showed the increased level of mineral nitrogen and salts in the observation sites located downstream from all 3 SHPs operating on the Arpa river, which was probably due to lower dilution rate caused by water intake by the SHPs. Based on the example of the Vardenis, Karchaghbyur and Arpa rivers, it’s possible to state that SHPs operation in Armenian river basins may cause a variety of environmental effects: unpredicted changes in the quantitative and qualitative compositions of hydrobiological communities such as phyto– and zooplankton; the destruction of river sections; the increased level of anthropogenic pollutants especially mineral nitrogen and salts; an obstacle to the migration and natural reproduction of fish species. Thus, the investigation on SHPs hydroecological risks has revealed a threat not only to hydrobiological components but also water qualitative properties. SHPs operation in Armenian river basins may cause water degradation, not only directly affecting river ecosystems but also intensifying anthropogenic pressure on them. Increasing growth in the Armenian hydropower sector will undoubtedly result in the acceleration of this process. To mitigate such environmental risks, responsible authorities need to develop and implement a new policy for SHPs operation, which will take into consideration not only economic benefits but also environmental safety. Therefore, further comprehensive investigation on the ecological aspect of SHPs operation will be implemented for the precise understanding of all sides of SHPs environmental effects. From the scientific point of view, the study results also have high international importance, since most such published works are for large hydroelectric units on big rivers, and the data presented for small hydropower units on small streams aren’t common and can be very important.

ACKNOWLEDGEMENTS

This work was supported by research project № YSSP-13-12 (NFSAT/YSSP) and the State Committee of Science of MES RA, research project № 15T–1F312.

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