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The volume of accessible groundwater in Latvia from a chosen aquifer is generally sufficient for a household or company to install a borehole with a flow rate of 10 m3/day or 100 m3/day. In this case, the main legal restrictions concern lowering the groundwater table to the minimum permissible level and the required water level reserve relative to the top of the well's filter column. Latvia is rich in groundwater water; for decision-makers to install a water intake well, it is usually sufficient to analyze data fr...

Presence of coastal structures usually causes significant impacts to adjacent shores, especially when they are composed of sand. Many times, these impacts are associated with inappropriate design due to inadequate consideration of hydromorphological processes and system interactions. As a result, excessive erosion and/or deposition of sediment is observed, which implies costly, and in some cases, continuous maintenance. The study presents an assessment and gives explanation of significant changes in the morphology...

Geographic information systems (GIS) are based on the approach of displaying data from individual layers, where a manageable number of geospatial objects are displayed within a single layer. The entire content of a hydrogeological model (HM) can only be partially included within this framework. HM input data and modeling results as layer surface maps are a way to easily, clearly, and simply publish the model content and simulation experiment results. However, this approach is not sufficient for regional HMs. Regio...

Water and sediments in coastal areas interact at different scales, thus shaping the marine environment and providing physical habitat for ecosystems. Hence, the hydromorphological conditions represent a key aspect of aquatic ecosystems considered in the Water Framework Directive as supporting quality elements (alongside the physicochemical), which are expected to provide the boundary conditions for the biological quality elements. Any alteration in those can reshape the corresponding biological conditions at vario...

Since putting in operation of Chernomorets fishing port (Sozopol municipality, southern Bulgarian Black Sea coast) in January 2016, a number of negative effects have been observed in the area. The disturbance in the existing hydrodynamic balance led to intense coastal erosion and unwanted sand accumulation in the wave shadow area. Additionally, the coastal water quality has deteriorated in the port area. In order to undertake measures to mitigate the observed adverse effects, it is necessary to assess in detail th...

The study presents results and discuss statistical properties of wind-generated sea waves measured in transitional waters of the Burgas Bay at the Bulgarian Black Sea. Wave measurements were acquired by Acoustic Doppler Current Profiler at two locations offshore Kraymorie and Chernomorets at water depths of approx. 15 m and 18 m, respectively. At each location, data were recorded for about three and a half months in winter seasons of 2021-2022 in front of Chernomorets and in 2022-2023 offshore Kraymorie, when stor...

Knowledge of the coastal hydrodynamics, in particular the storm induced waves, is essential for management of the extremely vulnerable coastal environment. There, wave processes dominate surge, coastal currents, sediment transport and species distribution. Therefore, it is important to have a detailed insight into the exposure of different coastal areas to wave action. The study proposes a wave exposure classification of the Bulgarian Black Sea coast according to wave climate conditions as required by the Water Fr...

Compliance with EU environmental regulations and directives regarding effluent water quality discharged is seen as the main driver for the development of wastewater treatment technologies. The Water Framework Directive, the UWWT Directive, and the Nitrates Directive require the reduction of eutrophication caused by nitrogen and phosphorus emissions. In Romania, only approx. 54% of the population is connected to centralized sewage and wastewater treatment systems, meaning that approximately 8 million inhabitants ar...

The theoretical model of perfect business competition is designed based on five assumptions: atomicity of demand and supply, homogeneity of the product, free entry/exit in/from a branch of activity or on/from the market, market transparency, (with the fundamental assumption of the individual's rationality) and perfect mobility of production factors [1], [2]. The factorial analysis carried out for an economic agent from an Eastern European country highlighted the fact that the production function is homogeneous. Fo...

Teichi bog is largest intact moss bog in the Baltics states. The article considers the hydrological exchange process of the bog and surrounding areas. It plays an important role in the ecosystem, as well as a factor in stabilizing the water level, as bog peat in its natural state contains 88%-97% water. It belongs to raised bogs, since its upper layer is located above the surrounding relief. Replenishment of water resources in the Teichi Nature Reserve occurs mainly due to precipitation. In turn, the bog with surf...

The safety of navigation and life in the risk areas adjacent to the coastal area, represent the central objective of the paper and meet the provisions of the European directive "in force." In this context, for defining the geometry of the autonomous modular system used as physical system for marking the fairway, mathematical prediction models were developed. The prediction of phenomena and functional characteristics for autonomous modular system was possible by using a specialized software, where the calculation c...

If the place hydrogeological conditions are uniform (invariable aquifer transmissivity, no impact of hydrogeological network) then the quarry depression cone and the pumping rate for the quarry draining can be obtained by using analytical methods. The dolomite aquifer at the Iecava district in Latvia included large impervious areas. Due to this fact, appliance of analytical methods cannot give the right depression cone. The local hydrogeological model (HM) was applied for obtaining the depression cone of the dolom...

Building of a shopping center was planed in Riga city, Latvia. Unfortunately, the center was located in the former dump site place where the about eight meters thick waste body contained an irregular mixture of oil products, Phenols, Detergents and metals: Copper, Lead and Chromium. It was presumed that these dissolved in groundwater contaminants should enter the nearby lake and dich. It was found out that cleaning of the place was not time and cost effective. It was necessary to reduce the concentration of these ...

In the Ropazu district at Latvia, a set of dolomite excavation quarries is located. Because the quarries must by drained by pumping out groundwater, depression cones appear in the quarry areas and around them. The research targets were investigation of the interaction between the quarries, evaluation of adverse changes caused by them in the groundwater regimes of the nature reserve wetland area «Lielie Kangari» and in flows of hydrographical network. The research was carried out by applying the hydrogeological mod...

The river is the consequential landscape ? forming element as it is rinsing and transporting the weakest rocks, scraping the bed and accumulating the sediment. During these processes in the river, diverse ecosystems are forming in various areas that provide habitats for a wide range of plant and animal species. In almost every river there is occurring a natural process as erosion. River erosion assessment should be considered in river management and included in management measures, as erosion can be determining fa...

In order to properly manage water resources in a river basin, it is necessary to identify trends in the evolution of rivers flow. Long-term trends analysis for river flow in north eastern part of Romania is based on two different methods: non-parametric rank-based Mann?Kendall (MK) test and innovative trend analysis (ITA). These two methods were applied for 7 hydrometric stations located in river basins unaffected by hydro-technical works, with hydrological observations on the average flow for the period 1950-2017...

The climate in Latvia is moderately warm and humid. To provide optimal groundwater heads (levels) for plant and tree growth, agricultural and forest melioration systems (AMS and FMS) have been set up in many places. Reconstruction of the FMS ?Zamelu-Tisu mezs? will be carried out. To assess the reconstruction impact, hydrogeological and hydrological conditions in and around the FMS territory were studied. To accomplish this task, specialists of Riga Technical University for the study area developed and used the lo...

Anthropogenic activities disrupt hydrological regime (e.g. lake water level, river flow), and water quality changes due to pollution and affect ecosystems by disrupting the cycles of substances and water cycle. The composition of natural surface waters can be altered for a many reasons, for instance climatic, geographic as well as anthropogenic. Agriculture depends on a use of fertilizers, a use of pesticides, and a transport which turn agricultural land into a nonpoint source of surface water pollution. The agglo...

As a result of increasing concentrations of total nitrogen and total phosphorus, surface water chemical pollution and eutrophication is a problem of raising concern worldwide. Chemical quality of surface water gives an impression about different geochemical, geological, hydrological and biological processes, as well as intensity of anthropogenic load in river catchment area. The total length of Svete River is 123 kilometres, of which 75 kilometres are in the territory of Latvia. Main part of river?s drainage basin...

In the current social and economic context it is necessary to evaluate the directions of administrative-territorial development and socio-economic vulnerability in relation to natural hazards, as the frequency of catastrophic phenomena tends to grow. In order to minimize the loss of human lives and to reduce the economic impact, it is necessary to implement an adequate territorial planning in relation to the spatial distribution of natural disasters. Most settlements from the region of Moldova are located / develo...

In recent years, oppression and even death of Baikal sponges has been noted. To monitor the state of the sponges and find out the reasons for their death, as well as to optimize the cultivation conditions and develop natural remediation measures, it is extremely important to have adequate biotesting methods based on changes in the physiological reaction of the sponges under the influence of adverse factors, including under the influence of various classes of pollutants. In view of the extremely low growth rate, va...

To evaluate hydrological drought in small basin was used minimum flow parameters like percentiles from the flow duration curve, mean annual minimum flow, base flow index and recession index. Water deficit was estimated based on threshold level method and the sequent peak algorithm. Each method was exemplified using data from hydrometric stations from small basins included in Bahlui drainage basin. The results show that in the period between 1950 and 2014, the average drought duration of the cold season is over 20 ...

In recent decades the increase of the frequency of flash-flood conditions requires a correct identification of potential flood areas where these hydrological risk phenomena appear in Moldavian Plain. To identify the basins and localities exposed to flash-flood was used physiographic method. This method allows the opportunity to identify the river basins with the concentration of water from precipitations in less than 6 hours. Through successive sorting of the basins which may generate the flash-flood was identifie...

The trace element composition of endorheic saline lakes (with total dissolved solids varies from 1 to 590 g/L) of the Altai Region (Russia) is of undoubted interest from the point of view of their mineral resources. Among the trace elements in lake waters, high content of boron (up to 78 mg/L), bromine (up to 820 mg/L), lithium (up to 3.6 mg/L), strontium (up to 13 mg/L), iodine (up to 6.3 mg/L), and arsenic (up to 0.6 mg/L) have been determined. The content of uranium in the investigated lakes varies over a wide ...

Rocks deep below the surface store heat and for every 100 m in depth the temperature increases by approximately 3oC. When the mines were closed, the mine galleries flooded. The heat of the rocks warms water, which is used as input to heat pumps for heating and cooling of buildings. The Remining-Lowex Project aims to demonstrate the use of water in abandoned coalmines as a source of renewable energy and to prove its economic viability. This new approach for utilization of sustainable energy from worked out coalmine...