Votkinsk Reservoir Research Articles

Decryption of snow cover on space images in spring period

The article is devoted to a comparative analysis of the results of snow cover interpreting on satellite images using various software tools on the example of individual basins in the catchment area of the Votkinsk Reservoir. Space images were decoded in ArcGIS and MultiSpec using the methods of interactive supervised classification with training and maximum similarity, and in the ScanEx Image Processor software- using NDSI and NDFSI indices. It was found that the use of the NDFSI index increases the accuracy of determining the areas occupied by snow for forested parts of the catchment by an average of 30%.

Changes in the annual and intra-annual river runoff of the Votkinsk reservoir’s catchment

The assessment of the long-term variability of the rivers water content in the catchment area of the Votkinsk Reservoir for gauge stations (g/s) with the longest observation series (1939–2018) has been carried out. During the period under review, almost all g/s showed the presence of a statistically significant positive linear trend. The difference-integral curves revealed a violation of the stationarity of long-term observation series, and an analysis of the intra-annual distribution of monthly and seasonal runoff in% of the annual for two periods was carried out: 1956–1976 and 1977–2018. For the period 1977–2018 a decrease in the share of spring runoff (by an average of 7%), as well as an increase in the share of summer-autumn runoff and winter runoff by 18.4 and 24%, respectively, were found for almost all rivers in the study area.

Оценка эколого-геохимического состояния аллювиальных почв пойм малых рек города Пермь

In the conditions of the city of Perm - a multidisciplinary industrial center of Russia, the regularities and quantitative characteristics of the redox and ecological-geochemical state of the soils of the floodplains of small rivers-tributaries of the Kama River within the Votkinsk reservoir are revealed. The regularities of the content, distribution and interrelation of potentially toxic chemical elements are established, the priority elements-pollutants, and their mobility in floodplain soils are determined. It was found that under the influence of heterogeneity of redox conditions, sorption, gley, and hydrogen sulfide geochemical barriers are formed in the soil profile. It was found that when hydrogenic pollution of urban alluvial soils occurs, natural-technogenic associations of chemical elements are formed in their profile, which differ from natural associations in the background soil. Elemental geochemical associations are characterized at different levels of technogenic load on the floodplains of small rivers. The relationship between the concentration of chemical elements and the value of the specific magnetic susceptibility in floodplain soils is determined. Keywords: REDOX STATE, HEAVY METALS, GEOCHEMICAL COEFFICIENTS, URBO-ALLUVIAL SOILS, CHEMOSEMS ON URBO-ALLUVIAL SOILS

Анализ возможных последствий крупномасштабной добычи песчано-гравийной смеси в нижних бьефах крупных гидроузлов на основе гидродинамического моделирования (на примере Воткинской ГЭС)

The authors have presented estimation of possible hydraulic consequences of the large-scale mining of sand/gravel mixtures in the upper part of the Lower Kama Reservoir 9the Votkinsk Reservoir downstream) based on the multi-version computation experiments with the developed hydro/dynamic model of the water body under consideration. This estimation is necessary for development of measures aimed at minimization of negative aftermath and provision of the interest balance between water users. Methods. The work is based on the conjugation of a set of field observations with computational experiments based on hydrodynamic models in 1D and 2D formulations, which make it possible to carry out hydrodynamic calculations for the waves of releases from HPPs. Results. The dynamics of water levels was investigated for various calculation scenarios, graphs were drawn for comparing water levels based on the results of calculations in one- and two-dimensional models for morphometry in 2019 in natural conditions and taking into account the development of deposits of sand and gravel mixtures. The experiments have demonstrated that development of only eight deposits (Volkovsk, Olkhovsk, Sivinsk, Golyanovo, Makarovsk, Upper-Dulesovsk, Simonikhinsk, and Simonikhinsk-2) will cause the necessity (in order to maintain the 3.3 m navigation depth) to increase the discharge to the Votkinsk HPP downstream up to 1800 m3/s or maintaining of continuous 1500 m3/s discharge for at least 24 hours. In the process of the water level graphs comparative analysis, both in one-dimension and two-dimension modeling, one can distinguish three sites with great level subsidence (15-41 cm) due to the large-scale mining of sand/gravel mixture.

COAST GEOMORPHOSYSTEMS OF THE RIGHT BANK OF THE VOTKINSK RESERVOIR

Methods and results of field studies of the complex of coastal processes on the right Bank of the Votkinsk reservoir are presented. They include observations of the rate of destruction and retreat of the walls of landslide-scree slopes, cut by abrasion, and processes that develop on the emerging shallows. For the first time, the processes of slow mass displacement of material entering the shallows due to the destruction of the banks were established and quantified within the shallow coastal waters. The main morphological types of coastal geomorphosystems are identified and the rates of re-formation are determined for their surface and underwater parts. It is noted that the most productive processes in relation to the flow of loose material into the reservoir bowl are the processes of shedding. Accordingly, weathering, as a source of loose material formation, acquires the importance of the most important shore-forming factor in the surface part of coastal geomorphosystems in the reservoir conditions. Among the most important lithodynamic flows of underwater sections of the coastal zone, the underwater "creep" is singled out. It was found that the layer of loose sediment lining the bench with a layer of 20-25 cm by the beginning of ice formation completely slides in the drying zone at a distance of 15-20 meters by the beginning of spring water discharge. Mass displacement of fine-grained earth occurs in the summer, but the slid material is actively replenished with abrasive products in the summer. Banks are destroyed by parallel retreat of the underwater and surface parts of the coast. At present, the rate of coastal destruction often increases rather than decreases, which makes it necessary to review some theoretical provisions concerning the laws of coastal development and forecast estimates. The results obtained can be used to estimate the rate of siltation of the reservoir basin.

Long-Term Changes in the Composition and Abundance of the Zooplankton Community in Kama River Reservoirs

In August 2016, the pelagic zooplankton (Cladocera, Copepoda, and Rotifera) and meroplankton (veligers of mollusks of g. Dreissena) were studied in four reservoirs of the Kama River (Kama, Votkinsk, and Nizhnekamsk reservoirs, and the Kama Reach of the Kuibyshev Reservoir). A total of 108 species were found; 14 species were new for the Kama River, including five crustaceans introduced from the Caspian Sea. Three of them (Heterocope caspia, Eurytemora caspica, and Cercopagis pengoi) spread northwards to the Kama Reservoir; two species (Cornigerius maeoticus and Calanipeda aquaedulcis) reached the upstream part of the Kuibyshev Reservoir’s Kama Reach. It is revealed that five southern species (Heterocope caspia, Diaphanosoma orghidani, Pompholyx sulcata, Conochiloides coenobasis and Asplanchna henrietta) first recorded in the Kama River in 2016, locally form high abundance. The summer zooplankton biomass averages 1.8 g/m3 in the Kama Reservoir, 1.3 g/m3 in the Niznekamsk Reservoir, 1.0 g/m3 in the Votkinsk Reservoir, and 0.5 g/m3 in the Kuibyshev Reservoir; its values are similar to those recorded in the 2000s. The changes in species composition, biological invasions, patterns of spatial distribution, and long-term changes in the zooplankton biomass are discussed.

The analysis of the channel deformations in the lower pool of the Votkinsk reservoir

The sand and gravel mix is mined at the Votkinsk reservoir. This leads to horizontal and vertical channel deformations. To study them, we examined the Golyanovsk section of the sand and gravel mix (SAGM) field in the lower pool of the reservoir. We used the channel surveys made in 2012-2016, 2018 and 2019 as the source of cartographic materials. The lower pool section of the Votkinsk hydroelectric complex, within which the Golyanovsk SAGM field is located, is characterized by a fully regulated effluent and an unsteady hydrological regime. Therefore, the hydrological regime of the considered area is particularly complex and depends on the water consumption in the alignment of the Votkinsk hydroelectric station and the level of the Nizhnekamsk reservoir. The average long-term water discharge for the navigation period is 2200 m3/s, the average long-term minimum monthly discharge rate is 1800 m3/s. The field survey of the area was carried out during the low water period in accordance. This period was characterized by minimum levels at around 64.79-65.24 m BS. The water discharge varied between 1720-1780 m3/s. With this flow, the Kama River is characterized by fairly low flow speed: no more than 1.29 m/s on the rod and 0.2-0.5 m/s on the riverbank shallows. The channel deposits are represented by pebble-gravel soils of various sizes. Throughout 2001-2019 an increase in the particle size has occurred. This is due to the change of the channel-forming process from accumulation to erosion. Horizontal deformations are represented by the reformation of the riverbanks, vertical – by accumulation and erosion of bottom. Drawdown levels are the result of natural deformations of the channel. According to the monitoring data, the duration of the “drawdown – growth” cycle is 2-3 years. The duration of the “drawdown – growth” cycle is 2-3 years.

Changes in River Ice Formation Dates and Tests for Their Statistical Significance Assessment

A methodological approach is developed to the analysis of long-term series of observations of hydrological characteristics including the testing of the hypothesis of randomness both for the full series and for their parts; the diagnosis of intraseries dependence of time series; the testing of the hypothesis of homogeneity of the parts of observations series under comparison; the identification of change points. Statistically significant changes in the dates of river ice formation in the Votkinsk Reservoir catchment were revealed for the periods of 1975–2012 and 1983–2012, whereas the entire observation period (1936–2012) did not reveal such changes. A possibility of localization of change points for the observation series was assessed using the inversion test.

Precipitation in the catchment area of the Votkinsk reservoir: nature, type and temporal variability

The type and nature of precipitation in the catchment area of the Votkinsk reservoir are considered with taking into account its hydrological zoning. Intra-annual frequency, duration and intensity of precipitation are shown. It is determined that 321 days are observed with precipitation per year on average. Daily amount does not exceed 1 mm. In the catchment area, widespread and rain precipitations are observed with a frequency of 51 and 53% respectively. The daily duration of precipitation depending on its type was obtained, which equals 4–6 h for rain and mixed precipitations and 8–10 h for solid precipitation. High precipitation intensity is observed in the northern part of the catchment area, where the terrain contributes to the development of cloudiness and an increase in precipitation intensity.

The study of long-term fluctuations in the dates of ice formation and ice destruction in the rivers of the Votkinsk reservoir catchment

A statistical analysis of the dates of ice formation and ice destruction in the rivers of the Votkinsk reservoir catchment was carried out, including testing the hypothesis of randomness for both the full series of observations and their parts; autocorrelation diagnostics of the time series; verification of the homogeneity hypothesis of the series of observations and the aggregate index. The results indicate that there are statistically significant changes in the ice formation and ice destruction dates occurring in recent years in the rivers of the Votkinsk reservoir catchment.

New Records of the Ponto-Caspian Predatory Cladoceran Cercopagis pengoi (Ostroumov, 1891) (Crustacea, Onychopoda) in the Water Reservoirs of the Kama and Volga Rivers

New habitats of the Ponto-Caspian cladoceran Cercopagis pengoi in the Tetyushi, Ulyanovsk, Volga-Kama, and Kama reaches of the Kuibyshev Reservoir; the upper part of the Votkinsk Reservoir; and the lower part of the Kama Reservoir (near the city of Perm) are revealed by comprehensive studies performed at the water reservoirs of the Volga and Kama Rivers in summer 2015 and 2016. The northernmost find of the invader species was recorded in the Kama River near the town of Dobryanka (58°26′ N); thus, the species was found ≥3° further to the north in the Kama River than in the Volga River (54°57′ N). The species inhabited the uppermost 5-m water layer and the typical C. (С.) pengoi form represented the species in all the water bodies. In August, Juveniles and parthenogenetic females (body length 1.2–2.0 mm) with 2–7 embryos were observed in the water bodies, and single finds of males were made. The population size of the invader species (≤100 ind/m3) was comparable to that of the taxonomically similar hybrid form of the genus Bythotrephes (B. brevimanus × B. cederstromii) that inhabits the same areas as C. pengoi does. The routes of dispersal and the distinctive features of the spatial distribution and ecology of the species are discussed.

Modeling the Spatial Distribution of Snow Cover during the Spring Snowmelt

The use of GIS technologies for modeling the spatial distribution of snow cover in spring is considered. The authors developed a method for the snowmelt calculation by the example of the Votkinsk Reservoir catchment area. It is proposed to take into account the uneven distribution of snow cover across the catchment depending on the terrain features. The paper estimates how the raster cell size variation affects the displaying the modeling results of the spatial distribution of snow cover.

A GIS-based modeling of snow accumulation and melt processes in the Votkinsk reservoir basin

Coupled hydrological and atmospheric modeling is an efficient method for snowmelt runoff forecast in large basins. We use short-range precipitation forecasts of mesoscale atmospheric Weather Research and Forecasting (WRF) model combining them with ground-based and satellite observations for modeling snow accumulation and snowmelt processes in the Votkinsk reservoir basin (184,319 km2). The method is tested during three winter seasons (2012–2015). The MODIS-based vegetation map and leaf area index data are used to calculate the snowmelt intensity and snow evaporation in the studied basin. The GIS-based snow accumulation and snowmelt modeling provides a reliable and highly detailed spatial distribution for snow water equivalent (SWE) and snow-covered areas (SCA). The modelling results are validated by comparing actual and estimated SWE and SCA data. The actual SCA results are derived from MODIS satellite data. The algorithm for assessing the SCA by MODIS data (ATBD-MOD 10) has been adapted to a forest zone. In general, the proposed method provides satisfactory results for maximum SWE calculations. The calculation accuracy is slightly degraded during snowmelt periods. The SCA data is simulated with a higher reliability than the SWE data. The differences between the simulated and actual SWE may be explained by the overestimation of the WRF-simulated total precipitation and the unrepresentativeness of the SWE measurements (snow survey).

Оценка деформаций русла реки Камы и разработка рекомендаций по регламентации добычи нерудных строительных материалов в пределах нижнего бьефа Камской ГЭС

This article considers issues of regulating the non-metallic building materials extraction in the lower reaches of large hydroelectric power plants. The problem is quite urgent when a large city is located in the lower tail of a hydroelectric power plant and the process of extraction of non-metallic building materials is superimposed on the rather complicated issues of interaction with other water users. The article employs the technique of mutual overlap of bathymetric surveys for the previous periods combined with the analysis of the declared volumes of extraction of non-metallic building materials. A simulating hydrodynamic model of the Votkinsk reservoir has been made, with taking into account the data on the fractional composition of bottom sediments. During the development of the model, we used the software products HEC-RAS v.4.1 and SMS v.11.1. The use of onedimensional and two-dimensional models made it possible to simplify calculations without significant loss of accuracy of calculations. Based on these models, a deformation of the bed was calculated under the standard conditions of the hydrological regime of the Kama and Votkinsk reservoirs. The outcome of the work is recommendations on the allocation of sites in the lower tail of the Kamskaya HPP, where the extraction of non-metallic building materials is not recommended, the areas where production is possible subject to a number of conditions and restrictions concerning the volume of production and areas where production is possible without restrictions.

Особенности формирования и расчета обратных течений в Воткинском водохранилище (1d-постановка)

Issues of the contraflows formation in the Votkinsk Reservoir (the middle one in the sequence of the Kama reservoirs) have been studied. The water discharge regime through the Kama Hydro Power Plant determines the contraflow occurrence. The importance of the contraflow issues is caused by the risk of contaminated waters input to water intakes located upstream in respect of the waste water outlets. One of the major industrial agglomeration, namely the Perm-Krasnokamsk cluster with numerous water intakes and waste water discharge points, is located in the upstream part of the Votkinsk Reservoir with is the downstream reach of the Kama Reservoir. On the basis of assessment of the contraflows scale and the consequences for water users the water/economic and environmental limitations are set for the power plant operation regime including sanitary discharge volumes. The contraflows have been simulated as a result of digital solution of the Saint-Venant equation in 1D-definintion with input of the first type boundary conditions directly in the vicinity of the Votkinsk Power Station dam. We have assessed the reservoir morphometry role in the contraflows formation. Outputs of the comparative experiments performed at different schematic models of the Votkinsk Reservoir have shown that reflection of the level lowering straight wave from the Votkinsk Power Station dam is the determining factor of the contraflows formation rather than peculiarities of the morphometry. When decreasing the period of water discharge to the downstream reach the zone of contraflows formation is displacing towards the Votkins Power Plant dam.

Simulation of snow accumulation and melt in the Votkinsk Reservoir catchment using the WRF-ARW model

Proposed is the method of computation of snow accumulation using the prognostic fields of precipitation based on the WRF-ARW mesoscale numerical model of the atmosphere that was tested using the data for 2012-2014. The snowmelt intensity in river catchments was computed by the method worked out by P.P. Kuz’min. This method is based on the solution of the equation of snow cover heat balance under assumption that the temperature of melting snow is equal to 0°C. The results of the modeling were validated by comparing the actual and computed snow accumulation and snow-covered area in the catchment under study. It is demonstrated that the proposed method based on prognostic fields of precipitation enables objective retrieving the spatial distribution of snow with the rather high spatial resolution, taking into account the terrain effects. The snow-covered area during the period of spring snowmelt is simulated with higher reliability than snow water equivalent. It is revealed that the difference between the simulated and actual snow accumulation reaching the maximum in spring, is caused both by the overestimation of precipitation amount by the WRF-ARW model and by the effects of local features of snow courses.

Long-term variability of ice formation dates on the rivers of the Votkinsk Reservoir catchment

Long-term variations of ice formation dates are studied using the long (more than 100 years) series of observations of ice regime on the rivers of the Votkinsk Reservoir catchment. Proposed is the methodological approach to assessing the long-term variability of these dates using both parametric and nonparametric statistical criteria.

Estimating the necessary duration of observation period in studying winter river runoff

A procedure for determining the minimal representative observation period at hydrological gages is proposed as required for studying the regularities in river runoff formation in rivers in the drainage basin of the Votkinsk Reservoir. Data of hydrological gages with long observational series were used as an example to show, by the division of these series into intervals and analysis of the obtained deviations from long-term mean values, that such minimal period can be taken to be 40 years long.

Современная морфометрия Воткинского водохранилища

Results of the Votkinsk Reservoir water area hydrographic studies with the aim to specify its morphometric parameters have been given; its reaches, hydrographic areas and sites’ morphometric indicators changes dynamics has been analyzed in comparison with the 1970 data; the hydrological/morphological zoning scheme has been updated, a digital model of the Votkinsk Reservoir bottom and banks relief has been derived; changes of the riparian area engineering/geological conditions upon the reservoir filling up to the forced level marks have been assessed; “The Votkinsk Reservoir Morphometry” GIS project has been developed.

Study of spatial distribution and occurrence frequency of ice jams in rivers of the Votkinsk reservoir catchment

In this paper, ice jams were studied and systemized for the first time for the Votkinsk reservoir catchment. For this purpose, observational and pooling data were used. The cartographic and attributive databases of sites where the jams occur were created by using GIS-technologies what allows obtaining their exact georeferences. Performed analysis of the studied river sections allowed revealing the main reasons of jamming.