Primerjava različnih analitičnih modelov za analizo spremembe gladine podzemne vode zaradi spremembe gladine v rečni akumulaciji : magistrsko delo

Skaza, Valentin (author), Vižintin, Goran (mentor)

Na območju srednje Save je načrtovana postavitev treh pretočno akumulacijskih hidroelektrarn (HE), in sicer HE Renke, HE Trbovlje in HE Suhadol. Zaradi izgradnje pregrad se bo za zajezbo ustvarila rečna akumulacija. Spremembe v nivojih površinske vode bodo posledično vplivale tudi na dvig nivojev podzemne vode. Obsežnejše raziskave se na območju izvajajo od leta 2009, ko so bili izvrtani piezometri, in z izvedbo črpalnih poskusov ugotovljene hidravlične lastnosti geoloških formacij. Monitoring nivojev podzemne vode se je izvajal z ročnimi popisi, na nekaterih piezometrih tudi zvezno z uporabo tlačnih sond. Zbrani in poenoteni so bili podatki o predhodnih raziskavah. Opravljena je bila analiza hidrogeološke situacije iz podatkov o popisih vrtin ter geoloških in hidrogeoloških kart. Analiza je bila izvedena v programski opremi QGIS, ki spada pod orodja GIS (Geografski informacijski sistem) in omogoča obdelavo ter analizo prostorskih podatkov. Na podlagi analize je bila situacija poenotena v hidrogeološke razrede. Na podlagi zbranih podatkov je bilo potrebno oceniti obseg vpliva dviga vode v akumulaciji na dvig podzemne vode v neposredni okolici reke. Za pomoč pri oceni vpliva so bile uporabljene analitične metode za enodimenzionalen tok podzemne vode. Izračun je bil narejen v programu MS Excel, rezultati pa nato prikazani z grafi. Zaradi nezveznosti podatkov so bili izračuni narejeni za izbrane karakteristične profile, ki so poimenovani po piezometrih, ki jih prečkajo, in za vsako pregrado hidroelektrarn. Ob upoštevanju hidrogeološke situacije so izračunani vplivi prikazani na karti, ki je bila ustvarjena v programu QGIS. Rezultati kažejo, da ima največji vpliv na podzemno vodo prepustnost geološke formacije, nato pa znižanje oz. višinska razlika med nivojem površinske in podzemne vode. Pri oceni vpliva je poleg izračunov upoštevana hidrogeološka situacija ter lokacijske posebnosti.

• Language: Slovenian
• Keywords: hidrogeologija, GIS, QGIS, tok podzemne vode, monitoring podzemne vode, piezometer
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: NTF - Faculty of Natural Sciences and Engineering
• Place of publishing: Ljubljana
• Publisher: [V. Skaza]
• Year: 2022
• Number of pages: XV, 65 f.
• PID: 20.500.12556/RUL-142321
• UDC: 622
• COBISS.SI-ID: 133653251
• Publication date in RUL: 29.10.2022

Secondary language

• Language: English
• Title: Comparison of different analytical models for analysing changes in groundwater level due to changes in river reservoir level : master's thesis

Abstract

Three run-off hydropower plants (HPP) with storage are planned to be built in the Central Sava River area, namely the Renke HPP, the Trbovlje HPP and the Suhadol HPP. The construction of the dams will result in river accumulation behind each dam. Changes in surface water levels will consequently also have an impact on the rise in groundwater head. More extensive field research of the area was carried out in 2009, when piezometers were installed, and pumping tests were carried out to determine the hydraulic properties of the geological formations. Groundwater levels have since been monitored manually and, in some piezometers, continuously using pressure probes. Data from previous research was collected and consolidated. The hydrogeological situation was analysed from borehole data, pumping tests, geological and hydrogeological maps. The analysis was carried out using QGIS software, a Geographic Information System (GIS) tool for processing and analysing spatial data. Based on the analysis, the situation has been unified into hydrogeological classes. The goal was to assess the extent to which the rise of water in the reservoir has an impact on the groundwater levels in the immediate vicinity of the stream, based on the data collected. Analytical methods for one-dimensional groundwater flow were used to assist in the impact assessment. The calculations were made in MS Excel and the results were exported as graphs. Due to uneven distribution of the available borehole data, the calculations were made for selected characteristic profiles, named after the piezometers, they cross, and for each barrier of the hydropower plants. Considering the hydrogeological situation, the calculated impacts are shown on a map generated in QGIS. The results show that the permeability of the geological formation has the greatest impact on groundwater, followed by the elevation difference between accumulation head and groundwater head. In addition to the calculations, the hydrogeological situation and local topography are taken into account in the impact assessment.

• Keywords: hydrogeology, GIS, QGIS, groundwater flow, groundwater monitoring, piezometer