scholarly journals Hydro-geological properties of the Savian aquifer in the county Obrenovac

Author(s):  
Dusan Stojadinovic ◽  
Zoran Nikic ◽  
Dusko Isakovic

The paper presents a description of hydrogeological researches of alluvial layers of the Sava River in the area of the source "Vic Bare" near Obrenovac. This source supplies groundwater to that town. The depth of these layers amounts to 25 m. With regard to collecting capacity, the most significant are gravel-sand sediments of high filtration properties. Their average depth amounts to about 13 m with the underlying layer made of Pleistocene clays. Compact aquifer is formed within these sediments and it refills partly from the Sava River at places where river cuts its channel into the gravel-sand layer. The analysis of the groundwater regime in the riparian area points out that groundwater levels follow stages of the Sava River. Such an influence lessens with the distance. Established hydraulic connection between the river and the aquifer enables its permanent replenishment. On the other hand, due to certain pollutions this river flow might bring along, it represents a potential danger. Those pollutions could enter water-bearing layer of the aquifer as well as the exploitation well of the source. Such presumptions have been confirmed in the experiment of pollution transport carried out in the water-bearing layer. Unabsorbable chloride was used as a tracer whose movement velocity through exploitation well proved that there were real possibilities of intrusion of aggressive pollutants into the water-bearing layer and into the aquifer as well. Therefore, the protection of the source must be in the function of the protection of surface waters.

Author(s):  
Hana Hornová ◽  
◽  
Ivana Černá ◽  

The planned construction of Oder-Danube canal was one of the largest activities, which led to the realization of research projects, which also included construction of boreholes for monitoring groundwater levels. Hydropedological profiles (HP) consist of boreholes, which are situated usually across the route of the canal and across longitudinal axis of valleys or flat Moravian hollows. They belong to basins of Oder, Bečva, Dyje (Thaya) and Morava rivers. First observations started back in 1933, subsequent followed after 1940. Nowadays these objects serve for obtaining general idea about the groundwater regime in valley profiles of these rivers. From geological perspective, these HP profiles are in an area of Quaternary sediments. Groundwater level monitoring at HP is important especially because of relating the profile to a particular watercourse and duration of the continuous monitoring. It can be used for determination of hydraulic link between surface water and groundwater. These values can be very useful especially in the determination of spread of potential groundwater pollutants via surface waters. Aim of the work is to assess course of groundwater levels at the Ladná profile of interest and to evaluate the effect of river engineering of the Dyje River on the groundwater regime, taking into account the drought period. Next aim of the work was to show the relationship with surface waters and evaluate the relationship between individual boreholes and the watercourse in the entire profile. In addition, long-term data series of groundwater level monitoring were used to perform evaluation of course of groundwater levels during various time periods, in particular during the individual reference periods, as specified by the CHMI, i.e. 1931-1960, 1931-1980 and the current reference period 1981-2010. Subsequently, the period 1991-2018 was also analyzed as a period associated with the current situation and finally also the entire period of monitoring, i.e. 1948-2018, a total of 70 years.


2018 ◽  
Vol 565 ◽  
pp. 365-373 ◽  
Author(s):  
Nives Ogrinc ◽  
David Kocman ◽  
Nada Miljević ◽  
Polona Vreča ◽  
Janja Vrzel ◽  
...  

Water ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1562
Author(s):  
Hrvoje Meaški ◽  
Ranko Biondić ◽  
Jelena Loborec ◽  
Dijana Oskoruš

With its quantities of groundwater, the Zagreb aquifer is an irreplaceable water-supply resource that forms the basis of the water-supply of Zagreb, the capital and largest city of the Republic of Croatia. The depth of the Zagreb aquifer system is about 100 m at the deepest part, and the two main aquifers of the aquifer system can be separated vertically by low-permeable clay deposits. In the area of the Zagreb aquifer, there are several active and reserve public water-supply sites, the largest of which are Mala Mlaka and Petruševec. The groundwater level of the Zagreb aquifer is directly related to the water levels of the Sava River, so any erosive change in the Sava riverbed decreases the groundwater levels in the aquifer. In the last 50 years, the groundwater levels in the Zagreb aquifer have decreased significantly, being most pronounced in the area of the Mala Mlaka water-supply site. This has affected the normal functioning of the public water-supply because the suction baskets of the pumps in the dug wells at the Mala Mlaka water-supply site occasionally remain partially or completely in the unsaturated aquifer zone during low groundwater levels, which reduces capacity or prevents pumping from these water-supply facilities. Immediately next to the Mala Mlaka water-supply site is the Sava-Odra Canal, which was built to protect Zagreb from flooding and into which the Sava River flows when its flow rate exceeds 2350 m3/s. This reduces the flow rate of the Sava River near Zagreb and the possibility of flooding urban areas. To prevent problems with groundwater levels at the Mala Mlaka water-supply facilities and to enable normal water-supply, even in extremely dry periods, several variants of managed aquifer recharge (MAR) are proposed here. In order to determine the optimal solution for MAR and to enable the normal functioning of one of the main sites of water-supply in the Zagreb water-supply system. Groundwater flow for the period of 2006 to 2010 was simulated for six different variants of MAR. One assumes a constant potential in the Sava-Odra Canal, three are related to recharge from the Sava-Odra Canal with different backwater levels in the infiltration facility (elevations of 114, 114.5, and 115 m a.s.l.), and two with three absorption wells upstream of the Mala Mlaka water pumping station (injection of 300 L/s each and 500 L/s each). The most favorable method to recharge artificially the Zagreb aquifer near the Mala Mlaka pumping station is achieved with an infiltration facility using an elevation of 115 m a.s.l. The use of such a facility will enable the smooth operation of the water pumping station and the possibility of increasing the pumping quantities at the Mala Mlaka water pumping station for the future development of the area.


Water ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 250
Author(s):  
Przemysław Tomalski ◽  
Edmund Tomaszewski ◽  
Dariusz Wrzesiński ◽  
Leszek Sobkowiak

The study applied the method of hydrological season identification in a time series of river total and base flows and in groundwater levels. The analysis covered a series of daily measurements from the period 2008–2017 in nine catchments located in different geographical regions of Poland. The basis of the classification of hydrological seasons, previously applied for river discharges only, was the transformation of the original variables into a series reflecting three statistical features estimated for single-name days of a year from a multiyear: average value, variation coefficient, and autocorrelation coefficient. New variables were standardized and after hierarchical clustering, every day of a year had a defined type, valorizing three features which refer to quantity, variability, and the stochastic nature of total and base river flow as well as groundwater stage. Finally, sequences of days were grouped into basic (homogenous) seasons of different types and transitional seasons including mixed types of days. Analysis indicated determinants of types, length, and frequency of identified hydrological seasons especially related to river regime, hydrogeological and hydrometeorological conditions as well as physiographical background were directly influenced by geographical location. Analysis of the co-occurrence of the same types of hydrological seasons allowed, in some catchments, periods of synchronic alimentation (groundwater and base flow, mainly in the cold half-year) and water shortages (all three components, mainly in the warm half-year) to be identified.


2010 ◽  
Vol 75 (1) ◽  
pp. 113-128 ◽  
Author(s):  
Simona Murko ◽  
Radmila Milacic ◽  
Marjan Veber ◽  
Janez Scancar

The applicability of nitric acid, palladium nitrate and a mixture of palladium and magnesium nitrate as matrix modifiers was estimated for the accurate and reproducible determination of cadmium (Cd), lead (Pb) and arsenic (As) in sediments of the Sava River by electrothermal atomic absorption spectrometry, ETAAS. Decomposition of the samples was done in a closed vessel microwave-assisted digestion system using nitric, hydrochloric and hydrofluoric acids, followed by the addition of boric acid to convert the fluorides into soluble complexes. The parameters for the determination of Cd, Pb and As in sediments were optimized for each individual element and for each matrix modifier. In addition, two sediment reference materials were also analyzed. In determination of Cd and Pb, nitric acid was found to be the most appropriate matrix modifier. The accurate and reliable determination of Cd and Pb in sediments was possible also in the presence of boric acid. The use of a mixture of palladium and magnesium nitrate efficiently compensated for matrix effects and enabled the accurate and reliable determination of As in the sediments. Quantification of Cd and As was performed by calibration using acid matched standard solutions, while the standard addition method was applied for the quantification of Pb. The repeatability of the analytical procedure for the determination of Cd, Pb and As in sediments was ?5 % for Cd, ?4 % for Pb and ?2 % for As. The LOD values of the analytical procedure were found to be 0.05 mg/kg for Cd and 0.25 mg/kg for Pb and As, while the LOQ values were 0.16 mg/kg for Cd and 0.83 mg/kg for Pb and As. Finally, Cd, Pb and As were successfully determined in sediments of the Sava River in Slovenia.


2011 ◽  
Vol 54 (1-2) ◽  
pp. 121-127 ◽  
Author(s):  
Nada Horvatinčić ◽  
Jadranka Barešić ◽  
Ines Krajcar Bronić ◽  
Bogomil Obelić ◽  
Krisztina Kármán ◽  
...  

2015 ◽  
Vol 15 (12) ◽  
pp. 2380-2386 ◽  
Author(s):  
Janja Vrzel ◽  
Nives Ogrinc

2016 ◽  
Vol 25 (1) ◽  
pp. 57-70 ◽  
Author(s):  
Zorana Mataruga ◽  
Snežana Jarić ◽  
Branko Karadžić ◽  
Miroslava Mitrović ◽  
Olga Kostić ◽  
...  
Keyword(s):  

Author(s):  
René Garreaud ◽  
Camila Alvarez-Garreton ◽  
Jonathan Barichivich ◽  
Juan Pablo Boisier ◽  
Duncan Christie ◽  
...  

Abstract. Since 2010 an uninterrupted sequence of dry years, with annual rainfall deficits ranging from 25 to 45 %, has prevailed in Central Chile (western South America, 30–38° S). Although intense 1- or 2-year droughts are recurrent in this Mediterranean-like region, the ongoing event stands out because of its longevity and large spatial extent. The extraordinary character of the so-called Central Chile Mega Drought (MD) was established against century long historical records and a millennial tree-ring reconstruction of regional precipitation. The largest MD-averaged rainfall relative anomalies occurred in the northern, semi-arid sector of central Chile but the event was unprecedented to the south of 35° S. ENSO neutral conditions have prevailed since 2011 (but for the strong El Niño 2015) contrasting with La Niña conditions that often accompanied past droughts. The precipitation deficit diminished the Andean snowpack and resulted in amplified declines (up to 90 %) of river flow, reservoir volumes and groundwater levels along central Chile and westernmost Argentina. In some semiarid basins we also found a conspicuous decrease in the runoff-to-rainfall coefficient. A substantial decrease in vegetation productivity occurred in the shrubland-dominated, northern sector, but a mix of greening and browning patches occurred farther south where irrigated croplands and exotic forest plantations dominate. The ongoing warming in central Chile, making the MD one of the warmest 6-year period on record, may have also contributed to such complex vegetation changes by increasing potential evapotranspiration. The understanding of the nature and biophysical impacts of the MD contributes to preparedness efforts to face a dry, warm future regional climate scenario.


Sign in / Sign up

Export Citation Format

Share Document