Groundwater Recharge Assessment Using Multi Component Analysis: Case Study at the NW Edge of the Varaždin Alluvial Aquifer, Croatia

Exploring the interaction between precipitation, surface water, and groundwater has been a key subject of many studies dealing with water quality management. The Varaždin aquifer is an example of an area where high nitrate content in groundwater raised public concern, so it is important to understand the aquifer recharge for proper management and preservation of groundwater quality. The NW part of the Varaždin aquifer has been selected for study area, as precipitation, Drava River, accumulation lake, and groundwater interact in this area. In this study, groundwater and surface water levels, water temperature, water isotopes (2H and 18O), and chloride (Cl−) were monitored in precipitation, surface water, and groundwater during the four-year period to estimate groundwater recharge. Head contour maps were constructed based on the groundwater and surface water levels. The results show that aquifer is recharged from both Drava River and accumulation lake for all hydrological conditions–low, mean, and high groundwater levels. The monitoring results of water temperature, chloride content, and stable water isotopes were used as tracers, i.e. as an input to the mixing model for estimation of the contribution ratio from each recharge source. The calculation of mixing proportions showed that surface water is a key mechanism of groundwater recharge in the study area, with a contribution ratio ranging from 55% to 100% depending on the proximity of the observation well to surface water.

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Quality of Surface Water and Groundwater in Iraq

10.47260/jesge/1124 ◽

2020 ◽

pp. 161-199

Author(s):

Nadhir Al-Ansari ◽

Sabbar Saleh ◽

Twana Abdullahand ◽

Salwan Ali Abed

Keyword(s):

Water Quality ◽

Drinking Water ◽

Surface Water ◽

Water Resources ◽

Middle East ◽

Human Life ◽

Water Levels ◽

Aquifer System ◽

Surface Water And Groundwater

Insufficiency of water resources in the Middle East Region represents vital factors that influence the stability of the region and its progress. Expectations indicate that the condition will be dimmer and more complicated, especially in Iraqi territory. Iraq, which is situated in the Middle East, it covers an area of 433,970 square kilometers and populated by about 32 million inhabitants. Iraq greatly relies in its water resources on the Tigris and Euphrates Rivers as a surface water resources, and several productive groundwater aquifers in which from the hydrogeological point of view divided into several major aquifer units including Foothill, Al-Jazira, Aquifer System, Mandali-Badra-Teeb, Mesopotamian and Desert Aquifer system. Recently, Iraq is suffering from water shortage problems. This is due to external and internal factors affecting the water quality of water resources; they are controlled and uncontrolled factors. The uncontrolled factors are climate change and its consequences, such as reduction of precipitation and temperature increasing. The controlled factors have a significantly negative influence on water resources, but their effects involve more specific regions. The controlled factors are mainly represented by building dams and irrigation projects within the upper parts of the Tigris and Euphrates catchments, Al-Tharthar Scheme, waste water, solid wastes and wastes from wars, which has a significant effect on surface water in Iraq because about 80% of the water supply to Euphrates and Tigris Rivers come from Turkey. In addition, the pressures resulting from the high demand for water resources, and the continued decline in their quantity rates have led to major changes in the hydrological condition in Iraq during the past 30 years. The decrease in surface water levels and precipitation during these three decades reflects the drop in the levels of water reservoirs, lakes, and rivers to the unexpected levels. The level of main country’s water source, Tigris, and Euphrates Rivers has fallen to less than a third of its natural levels. As storage capacity depreciates, the government estimates that its water reserves have been reduced precariously. According to the survey from the Ministry of Water Resources, millions of Iraqi people have faced a severe shortage of drinking water. Since of the importance of water for human life and the need to monitor temporal and spatial changes in quality and quantity, there is a need to develop a general Iraqi Water Quality Index (Iraq WQI) to monitor surface water and groundwater and classify it into five categories, very good, good, acceptable, bad and very bad, in terms of suitability for domestics, irrigation and agriculture depending on the Iraqi and WHO standards for drinking water. In addition, strict establishment for the regular quantitative monitoring surface water and groundwater setting and processes. Prospects are more negative for all riparian countries. This implies that solving these problems requires actual and serious international, regional, and national cooperation to set a prudent plan for water resources management of the two basins. Iraq being the most affected country should seriously set a prudent, scientific, and strategic plan for the management and conservation of its water resources. Keywords: Pollution, Water Quality, Waste, Surface water, Groundwater, Iraq.

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Factors influencing surface water and groundwater interaction in alluvial fan

Journal of Water and Climate Change ◽

10.2166/wcc.2020.174 ◽

2020 ◽

Author(s):

Fanao Meng ◽

Changlai Xiao ◽

Xiujuan Liang ◽

Ge Wang ◽

Ying Sun ◽

...

Keyword(s):

Surface Water ◽

River Runoff ◽

Groundwater Level ◽

Alluvial Fan ◽

Water Levels ◽

Key Factors ◽

Groundwater Exploitation ◽

Factors Affecting ◽

Surface Water And Groundwater ◽

The Relationship

Abstract In this study, the surface water balance method was used to calculate the interaction between surface water and groundwater (SGW) in the Taoer River alluvial fan in Jilin Province, China, from 1956 to 2014. The automatic linear model was used to determine the key and non-key influencing factors, and correlation analysis was performed to evaluate their relationship with one another. River runoff and groundwater level were the key factors affecting the SGW interaction, and sand–gravel exposure in the fan was more conducive to SGW interaction. There was a positive correlation between runoff and SGW interaction, and the relationship between the groundwater and surface water levels was correlated and affected by groundwater exploitation and groundwater runoff. Groundwater exploitation and evaporation and precipitation indirectly influenced the SGW interaction by affecting the groundwater level and river runoff key factors, respectively, and were considered non-key factors.

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Groundwater recharge in the oasis-desert areas of northern Tarim Basin, Northwest China

Hydrology Research ◽

10.2166/nh.2020.071 ◽

2020 ◽

Vol 51 (6) ◽

pp. 1506-1520

Author(s):

Weihua Wang ◽

Yaning Chen ◽

Wanrui Wang

Keyword(s):

Stable Isotopes ◽

Surface Water ◽

Groundwater Recharge ◽

Tarim Basin ◽

Shallow Groundwater ◽

Northwest China ◽

Water Infiltration ◽

Ecological Processes ◽

Surface Water And Groundwater ◽

Northern Tarim Basin

Abstract Groundwater is an important source for maintaining desert ecological processes in arid areas. With the increasing intensity of climate change and human activities, the rivers in Tarim Basin are severely dried-up. Aiming at the dried-up river, vegetation degradation and oasis maintenance in the middle and lower reaches of dried-up river basin, groundwater recharge and groundwater-surface water interaction have become hotspots, but are not well known. We examined spatial distributions and controlling factors of groundwater stable isotopes and recharge at oasis scale using data from 247 samples surveyed in the four headwaters in the northern Tarim Basin. Stable isotopes of surface water and groundwater were different from each other, and varied among sampling sites. Surface water and groundwater isotopes generally became enriched towards the east throughout the study area, while surface water isotopes showed enrichment towards the upstream direction within each catchment, mainly due to cultivated area expansion. Surface water mainly originated from precipitation, groundwater, and meltwater, while shallow groundwater derived from lateral groundwater flow, river and irrigated water infiltration, and little precipitation. The mainstream water was directly recharged by the headwaters. The results could provide a new insight into groundwater cycling in oases of dried-up river basins, which is helpful for regional groundwater management.

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Climate Change Impact on Surface Water and Groundwater Recharge in Northern Thailand

Water ◽

10.3390/w12041029 ◽

2020 ◽

Vol 12 (4) ◽

pp. 1029 ◽

Cited By ~ 3

Author(s):

Chanchai Petpongpan ◽

Chaiwat Ekkawatpanit ◽

Duangrudee Kositgittiwong

Keyword(s):

Climate Change ◽

Surface Water ◽

Groundwater Recharge ◽

River Basin ◽

Climate Change Impact ◽

Annual Rainfall ◽

Northern Thailand ◽

Surface Water And Groundwater ◽

Rcp 8.5 ◽

Change Impact

Climate change is progressing and is now one of the most important global challenges for humanities. Water resources management is one of the key challenges to reduce disaster risk. In Northern Thailand, flood and drought have always occurred because of the climate change impact and non-systematic management in the conjunctive use of both sources of water. Therefore, this study aims to assess the climate change impact on surface water and groundwater of the Yom and Nan river basins, located in the upper part of Thailand. The surface water and groundwater regimes are generated by a fully coupled SWAT-MODFLOW model. The future climate scenarios are considered from the Representative Concentration Pathways (RCPs) 2.6 and 8.5, presented by the Coupled Model Intercomparison Project Phase 5 (CMIP5), in order to mainly focus on the minimum and maximum Green House Gas (GHG) emissions scenarios during the near future (2021–2045) periods. The results show that the average annual air temperature rises by approximately 0.5–0.6 °C and 0.9–1.0 °C under the minimum (RCP 2.6) and maximum (RCP 8.5) GHG emission scenarios, respectively. The annual rainfall, obtained from both scenarios, increased by the same range of 20–200 mm/year, on average. The summation of surface water (water yield) and groundwater recharge (water percolation) in the Yom river basin decreased by 443.98 and 316.77 million m3/year under the RCPs 2.6 and 8.5, respectively. While, in the Nan river basin, it is projected to increase by 355 million m3/year under RCP 2.6 but decrease by 20.79 million m3/year under RCP 8.5. These quantitative changes can directly impact water availability when evaluating the water demand for consumption, industry, and agriculture.

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Development of a coupled simulation framework representing the lake and river continuum of mass and energy (T-CHOIR v1.0)

10.5194/gmd-2021-75 ◽

2021 ◽

Author(s):

Daisuke Tokuda ◽

Hyungjun Kim ◽

Dai Yamazaki ◽

Taikan Oki

Keyword(s):

Surface Water ◽

Water Temperature ◽

Numerical Models ◽

Water Levels ◽

Geographical Information ◽

Modeling Framework ◽

Coupled Mode ◽

Rivers And Lakes ◽

Tightly Coupled

Abstract. Terrestrial surface water temperature is a key variable affecting water quality and energy balance, and thermodynamics and fluid dynamics are tightly coupled in fluvial and lacustrine systems. Streamflow generally plays a role in the horizontal redistribution of heat, and thermal exchange in lakes predominantly occurs in a vertical direction. However, numerical models simulate the water temperature for uncoupled rivers and lakes, and the linkages between them on a global scale remain unclear. In this study, we proposed an integrated modeling framework: Tightly Coupled framework for Hydrology of Open water Interactions in River–lake network (T-CHOIR). The objective is to simulate terrestrial fluvial and thermodynamics as a continuum of mass and energy in solid and liquid phases redistributed among rivers and lakes. T-CHOIR uses high-resolution geographical information harmonized over fluvial and lacustrine networks. The results have been validated through comparison with in-situ observations and satellite-based data products, and the model sensitivity has been tested with multiple meteorological forcing datasets. It was observed that the coupled mode outperformed the river-only mode in terms of discharge and temperature in downstream of lakes; it was also observed that seasonal and interannual variation in lake water levels and temperature are also more reliable in the coupled mode. The inclusion of lakes in the coupled model resulted in an increase in river temperatures during winter in mid-latitudes and a decrease in temperatures during summer in high latitudes, which reflects the role of lakes as a form of large heat storage. The river–lake coupling framework presented herein provides a basis for further elucidating the role of terrestrial surface water in in Earth’s energy cycle.

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Climate-Dependent Groundwater Discharge on Semi-Arid Inland Ephemeral Wetlands: Lessons from Holocene Sediments of Lagunas Reales in Central Spain

Water ◽

10.3390/w12071911 ◽

2020 ◽

Vol 12 (7) ◽

pp. 1911

Author(s):

Rosa Mediavilla ◽

Juan I. Santisteban ◽

Ignacio López-Cilla ◽

Luis Galán de Frutos ◽

África de la Hera-Portillo

Keyword(s):

Surface Water ◽

Water Balance ◽

Classical Model ◽

Sedimentary Facies ◽

Human Action ◽

Water Levels ◽

Central Spain ◽

Saline Groundwater ◽

Surface Water And Groundwater ◽

Semi Arid

Wetlands are environments whose water balance is highly sensitive to climate change and human action. This sensitivity has allowed us to explore the relationships between surface water and groundwater in the long term as their sediments record all these changes and go beyond the instrumental/observational period. The Lagunas Reales, in central Spain, is a semi-arid inland wetland endangered by both climate and human activity. The reconstruction of the hydroclimate and water levels from sedimentary facies, as well as the changes in the position of the surface water and groundwater via the record of their geochemical fingerprint in the sediments, has allowed us to establish a conceptual model for the response of the hydrological system (surface water and groundwater) to climate. Arid periods are characterized by low levels of the deeper saline groundwater and by a greater influence of the surface freshwater. A positive water balance during wet periods allows the discharge of the deeper saline groundwater into the wetland, causing an increase in salinity. These results contrast with the classical model where salinity increases were related to greater evaporation rates and this opens up a new way of understanding the evolution of the hydrology of wetlands and their resilience to natural and anthropogenic changes.

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Development of a coupled simulation framework representing the lake and river continuum of mass and energy (TCHOIR v1.0)

Geoscientific Model Development ◽

10.5194/gmd-14-5669-2021 ◽

2021 ◽

Vol 14 (9) ◽

pp. 5669-5693

Author(s):

Daisuke Tokuda ◽

Hyungjun Kim ◽

Dai Yamazaki ◽

Taikan Oki

Keyword(s):

Surface Water ◽

Water Temperature ◽

Numerical Models ◽

Water Levels ◽

Geographical Information ◽

Modeling Framework ◽

Coupled Mode ◽

Rivers And Lakes ◽

Tightly Coupled

Abstract. Terrestrial surface water temperature is a key variable affecting water quality and energy balance, and thermodynamics and fluid dynamics are tightly coupled in fluvial and lacustrine systems. Streamflow generally plays a role in the horizontal redistribution of heat, and thermal exchange in lakes predominantly occurs in a vertical direction. However, numerical models simulate the water temperature for uncoupled rivers and lakes, and the linkages between them on a global scale remain unclear. In this study, we proposed an integrated modeling framework: Tightly Coupled framework for Hydrology of Open water Interactions in River–lake network (TCHOIR, read as “tee quire”). The objective is to simulate terrestrial fluvial and thermodynamics as a continuum of mass and energy in solid and liquid phases redistributed among rivers and lakes. TCHOIR uses high-resolution geographical information harmonized over fluvial and lacustrine networks. The results have been validated through comparison with in situ observations and satellite-based data products, and the model sensitivity has been tested with multiple meteorological forcing datasets. It was observed that the “coupled” mode outperformed the “river-only” mode in terms of discharge and temperature downstream of lakes; moreover, it was observed that seasonal and interannual variation in lake water levels and temperature are also more reliable in the “coupled” mode. The inclusion of lakes in the coupled model resulted in an increase in river temperatures during winter at midlatitudes and a decrease in temperatures during summer at high latitudes, which reflects the role of lakes as a form of large heat storage. The river–lake coupling framework presented herein provides a basis for further elucidating the role of terrestrial surface water in Earth's energy cycle.

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