Fluctuation Effect of Reservoir Water Level on the Seepage of Earth-Fill Dam

Lots of dam failures are the result of uncontrolled seepage. The collapse of the Situ Gintung Dam in Tangerang, Banten-Indonesia in 2009 due to heavy rains caused the dam structure to collapse. This is due to increased pore water pressure in the landfill. To anticipate collapse due to uncontrolled seepage, it is necessary to monitor it based on the behavior of changes in rainfall and reservoir water levels. Seepage within the dam body is often monitored using instrumentation tools such as standpipe piezometer (standpipe piezometer) or electric piezometer. But often the piezometer cannot work properly because it is clogged, so it cannot monitor the condition of the seepage. Other instrumentations such as V-Notch are also used to measure seepage discharge. This study aims to determine the behavior of changes in the reservoir water level caused by changes in rainfall and its effect on body seepage of the earth-fill Type dam. By knowing the phenomenon of the behavior of the relationship between reservoir water infiltration and rainfall, it will obtain information on rainfall that endangers the dam which will affect the downstream. In this study, a case study of the Selorejo Dam was taken which has a large enough reservoir capacity of about 31 million m3 which is included in the Brantas River Basin. The results showed that 5 piezometers devices were damaged (SL 1, SL 2, SL 4, SL 6, and SL 7) where they could not read the phreatic water level properly, and 2 piezometers were less sensitive to reading fluctuations in reservoir water levels. namely SL 10 and SL 11 which showed R2 values of 29.78% and 39.4%, respectively. While the maximum seepage discharge is recorded at 1474 liters/minute, this is still below the critical discharge of 1630 liters/minute allowed for this dam, but this needs to be a concern, especially the discharge from toe drain from the left side seepage and C-area which is the leakage from the left support pedestal also contributes a larger discharge than other observation points.

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Experimental and numerical study of upstream slope stability in an earth dam reservoir under rapid drawdown conditions

Innovaciencia Facultad de Ciencias Exactas Físicas y Naturales ◽

10.15649/2346075x.1006 ◽

2020 ◽

Vol 8 (1) ◽

pp. 1-15

Author(s):

Seyed Habib Mousavi Jahromi ◽

Mansour Pakmanesh ◽

Amir Khosrojerdi ◽

Hossein Hassanpour Darvishi ◽

Hossein Babazadeh

Keyword(s):

Water Level ◽

Pore Water Pressure ◽

Numerical Study ◽

Water Pressure ◽

Earth Dam ◽

Dam Reservoir ◽

Reservoir Water ◽

Reservoir Water Level ◽

Seepage Analysis ◽

Upstream Slope

The rapid ‎drawdown of the dam reservoir is one of the most common situations occurring in the lifetime of a dam. For this reason, one of the main factors in the design of the upstream slope is the rapid drainage of the reservoir. In this case, the upstream slope is in a critical condition and the slope may be unstable. When the water surface in the reservoir is drawdown suddenly, the water level in the dam body does not decrease at the same time as the reservoir water level. The analysis of seepage from the earth dam body and calculation of the water loss play an important role in calculating the amount of pore water pressure, and, consequently, the stability analysis of the dam body. In addition, any seepage analysis is dependent on the hydraulic properties of the dam materials. In order to investigate the effect of hydraulic conductivity on the rapid drawdown of water level and the seepage, an experimental model was constructed of an earth dam. By accurate measurement of hydraulic parameters of the materials in saturated and unsaturated media, the flow through this model was modeled using a disk penetrometer by seep/w software. The results were then compared with the observed data.

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The Analysis about Seepage of the Bank Slope under the Cycle Rising and Drawdown of Reservoir Water Level

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.353-356.112 ◽

2013 ◽

Vol 353-356 ◽

pp. 112-115

Author(s):

Xiao Wen Liu ◽

Wen Wan ◽

Xi Zhong Shen

Keyword(s):

Water Level ◽

Pore Water Pressure ◽

Water Pressure ◽

Reservoir Water ◽

Reservoir Water Level ◽

Bank Slope ◽

Saturation Region ◽

Distribution Laws ◽

Seepage Theory ◽

Stabilization Period

Bank slope seepage field is analyzed by saturated-unsaturated seepage theory under the three times cycle conditions of water level rising and drawdown . The pore water pressure distribution laws of the water level rising period, the stabilization period, the period of decline and decline stable period for every cycle are researched. The result shows soil near slope region is saturated easily after many rounds of water level rising and drawdown, and saturation region gradually increases. Soil phreatic line near slope falls fastly in the drawdown period, away from the slope, phreatic line declines slowly.

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The Monitoring-Based Analysis on Deformation-Controlling Factors and Slope Stability of Reservoir Landslide: Hongyanzi Landslide in the Southwest of China

Geofluids ◽

10.1155/2018/7391517 ◽

2018 ◽

Vol 2018 ◽

pp. 1-14 ◽

Cited By ~ 3

Author(s):

Bing Han ◽

Bin Tong ◽

Jinkai Yan ◽

Chunrong Yin ◽

Liang Chen ◽

...

Keyword(s):

Water Level ◽

Water Pressure ◽

Monitoring Program ◽

Significant Risk ◽

Controlling Factors ◽

Seepage Water ◽

Reservoir Water ◽

Reservoir Water Level ◽

Reservoir Area ◽

Reservoir Landslide

Reservoir landslide is a type of commonly seen geological hazards in reservoir area and could potentially cause significant risk to the routine operation of reservoir and hydropower station. It has been accepted that reservoir landslides are mainly induced by periodic variations of reservoir water level during the impoundment and drawdown process. In this study, to better understand the deformation characters and controlling factors of the reservoir landslide, a multiparameter-based monitoring program was conducted on a reservoir landslide—the Hongyanzi landslide located in Pubugou reservoir area in the southwest of China. The results indicated that significant deformation occurred to the landslide during the drawdown period; otherwise, the landslide remained stable. The major reason of reservoir landslide deformation is the generation of seepage water pressure caused by the rapidly growing water level difference inside and outside of the slope. The influences of precipitation and earthquake on the slope deformation of the Hongyanzi landslide were insignificant.

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Application of Neural Network Models and ANFIS for Water Level Forecasting of the Salve Faccha Dam in the Andean Zone in Northern Ecuador

Water ◽

10.3390/w13152011 ◽

2021 ◽

Vol 13 (15) ◽

pp. 2011

Author(s):

Pablo Páliz Larrea ◽

Xavier Zapata Ríos ◽

Lenin Campozano Parra

Keyword(s):

Neural Network ◽

Water Level ◽

Clustering Algorithm ◽

Network Models ◽

Water Levels ◽

Subtractive Clustering ◽

Neural Network Models ◽

Reservoir Water ◽

Reservoir Water Level ◽

Maximum Delay

Despite the importance of dams for water distribution of various uses, adequate forecasting on a day-to-day scale is still in great need of intensive study worldwide. Machine learning models have had a wide application in water resource studies and have shown satisfactory results, including the time series forecasting of water levels and dam flows. In this study, neural network models (NN) and adaptive neuro-fuzzy inference systems (ANFIS) models were generated to forecast the water level of the Salve Faccha reservoir, which supplies water to Quito, the Capital of Ecuador. For NN, a non-linear input–output net with a maximum delay of 13 days was used with variation in the number of nodes and hidden layers. For ANFIS, after up to four days of delay, the subtractive clustering algorithm was used with a hyperparameter variation from 0.5 to 0.8. The results indicate that precipitation was not influencing input in the prediction of the reservoir water level. The best neural network and ANFIS models showed high performance, with a r > 0.95, a Nash index > 0.95, and a RMSE < 0.1. The best the neural network model was t + 4, and the best ANFIS model was model t + 6.

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Analysis of Pore Water Pressure and Piping of Hydraulic Well

Water ◽

10.3390/w13040502 ◽

2021 ◽

Vol 13 (4) ◽

pp. 502

Author(s):

Jinman Kim ◽

Heuisoo Han ◽

Yoonhwa Jin

Keyword(s):

Numerical Analysis ◽

Water Level ◽

Pore Water ◽

Large Scale ◽

Pore Water Pressure ◽

Water Pressure ◽

Hydraulic Gradient ◽

Water Levels ◽

Seepage Velocity ◽

Seepage Analysis

This paper shows the results of a field appliance study of the hydraulic well method to prevent embankment piping, which is proposed by the Japanese Matsuyama River National Highway Office. The large-scale embankment experiment and seepage analysis were conducted to examine the hydraulic well. The experimental procedure is focused on the pore water pressure. The water levels of the hydraulic well were compared with pore water pressure data, which were used to look over the seepage variations. Two different types of large-scale experiments were conducted according to the installation points of hydraulic wells. The seepage velocity results by the experiment were almost similar to those of the analyses. Further, the pore water pressure oriented from the water level variations in the hydraulic well showed similar patterns between the experiment and numerical analysis; however, deeper from the surface, the larger pore water pressure of the numerical analysis was calculated compared to the experimental values. In addition, the piping effect according to the water level and location of the hydraulic well was quantitatively examined for an embankment having a piping guide part. As a result of applying the hydraulic well to the point where piping occurred, the hydraulic well with a 1.0 m water level reduced the seepage velocity by up to 86%. This is because the difference in the water level between the riverside and the protected side is reduced, and it resulted in reducing the seepage pressure. As a result of the theoretical and numerical hydraulic gradient analysis according to the change in the water level of the hydraulic well, the hydraulic gradient decreased linearly according to the water level of the hydraulic well. From the results according to the location of the hydraulic well, installation of it at the point where piping occurred was found to be the most effective. A hydraulic well is a good device for preventing the piping of an embankment if it is installed at the piping point and the proper water level of the hydraulic well is applied.

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Interpretasi Instrumentasi Piezometer Dalam Rangka Pemantauan Keamanan Bendungan Kedung Ombo

SIKLUS Jurnal Teknik Sipil ◽

10.31849/siklus.v7i2.7460 ◽

2021 ◽

Vol 7 (2) ◽

pp. 131-145

Author(s):

Gerald Guntur Pandapotan Siregar ◽

Fajar aldoko Kurniawan

Keyword(s):

Pore Water ◽

Pore Water Pressure ◽

Water Pressure ◽

Water Level Fluctuations ◽

Embankment Dam ◽

Reservoir Water ◽

Reservoir Water Level ◽

Embankment Dams ◽

The World ◽

Earthfill Dams

The embankment dam is the most widely built dam in the world, especially in Indonesia. However, embankment dams are also prone to collapse. Dam failures due to the piping process through the dam body account for 30.5% of the total dam collapses worldwide. Therefore, it is necessary to periodically monitor and evaluate the condition of pore water pressure and seepage in a dam which is usually carried out using installed instrumentation. Very little has been done on instrumentation interpretation of earthfill dams in Indonesia, which is a very worrying condition. It is possible that old or even new dams have shown behavior that leads to a decrease in safety. This condition can be monitored by instrumentation in the dam if interpreted properly. Kedung Ombo Dam as an old embankment dam but has a fairly complete instrumentation can be evaluated for safety related to pore water pressure and phreatic line (seepage line). Pore water pressure evaluation is carried out by collecting piezometer readings and reservoir water level fluctuations over a period of several years. The results of the research on the interpretation of piezometer readings indicate that the overall safety of the Kedung Ombo dam is still good in terms of pore water pressure conditions. However, there are some anomalous conditions that should be investigated further

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Research and Application of Key Technologies for Dynamic Control of Reservoir Water Level in Flood Season

Water ◽

10.3390/w13243576 ◽

2021 ◽

Vol 13 (24) ◽

pp. 3576

Author(s):

Jun Zhang ◽

Yaowu Min ◽

Baofei Feng ◽

Weixin Duan

Keyword(s):

Water Supply ◽

Water Level ◽

Real Time ◽

Flood Control ◽

Dynamic Control ◽

Water Levels ◽

Reservoir Water ◽

Reservoir Water Level ◽

Danjiangkou Reservoir ◽

Flood Season

In today’s reservoir operation study, it is urgent to solve the issues on improving flood resource utilization, maximizing reservoir impoundment, and guaranteeing water supply through real-time regulation optimization under the premise of ensuring flood control safety and taking risks properly. Based on previous studies, the key real-time operation technologies for dynamic control of reservoir water levels in flood season are summarized. The Danjiangkou Reservoir was taken as an example, the division of flood stages, reservoir water level requirements for improving water supply guarantee, dynamic control indexes of reservoir water level for beneficial use in stages during the flood season, and flood control dispatching indexes are proposed. Moreover, a practicable real-time flood forecast operation scheme for Danjiangkou Reservoir was compiled. Its application in 2017 indicated that the established scheme can provide strong technical support to ensure the overall benefits of Danjiangkou Reservoir, including flood control, water supply, and power generation.

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ICESat-2 Reservoir Applications: A case study from the largest man-made reservoir in India

10.31223/x5dk9d ◽

2021 ◽

Author(s):

Surajit Ghosh ◽

Atul Kaushik

Keyword(s):

Water Level ◽

Water Levels ◽

Water Bodies ◽

Reservoir Water ◽

Reservoir Water Level ◽

Reservoir Storage ◽

Inland Water ◽

Change Impact ◽

And Performance ◽

Inland Water Bodies

Monitoring inland water levels is crucial for understanding hydrological processes to climate change impact leading to policy implementation. Satellite altimetry has proved to be an excellent technique to precisely measure water levels of rivers, lakes, and other inland water bodies. The ATL13 product of ICESat-2 space-borne LiDAR is solely dedicated to inland water bodies. The water surface heights were derived from ICESat-2's strong beams, and performance was assessed with respect to reservoir gauge observations. Statistical measurements were used to understand the agreement (R2= 0.99, %RMSE=0.08) among the datasets. An R2 value of 0.99 was observed between ICESat-2 derived water level anomaly and the reservoir storage anomaly. This study provides a unique opportunity to utilize the ATL13 data product to study reservoir water level variation and estimate the reservoir's storage. The methodology can also be helpful to understand the reservoir storage variation in a data-sparse region.

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Deformation and stability analyses of a near-dam rocky slope and its potential landslide-generated wave threats

Quarterly Journal of Engineering Geology and Hydrogeology ◽

10.1144/qjegh2021-018 ◽

2021 ◽

pp. qjegh2021-018

Author(s):

Ming-liang Chen ◽

Xing-guo Yang ◽

Shun-chao Qi ◽

Hai-bo Li ◽

Jia-wen Zhou

Keyword(s):

Water Level ◽

Rock Slope ◽

Limit Equilibrium ◽

Water Levels ◽

Reservoir Rock ◽

Water Diversion ◽

Reservoir Water ◽

Reservoir Water Level ◽

The Impact

Occurrence of a reservoir landslide and its potential secondary hazards near a dam can result in significant losses and casualties, such as those that resulted from the Vajont landslide. In this study, a cataclinal rock slope in the Maoergai reservoir was taken as a case to study the characteristics of the gravitational deformation process and to analyze the potential threat. The stability of rock slope is analyzed by the limit equilibrium method, and the potential landslide movement and subsequent waves are also simulated. Results indicate that lithology, geological structure, reservoir water level changes and artificial activities all play an important role for the large deformation of rock slope deformation, which is characterized by a combination of bending-toppling and principally shear-slip. Pre-calculations of potential threats indicated that the impact of a landslide wave would be greater at dead water levels than at the normal water level and could result in blockage of the inlet to the water diversion structure on the opposite right bank. These findings provide implication for the control of reservoir rock slopes: (i) serious attention should be paid to the influence of water on rock strength in early and (ii) infiltration must be prevented during water level rise.Thematic collection: This article is part of the Role of water in destabilizing slopes collection available at: https://www.lyellcollection.org/cc/Role-of-water-in-destabilizing-slopes

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Stability of No 7 Landslide Located at Ciha Gorge under the Condition of Reservoir Water Level Rise

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.368-373.1482 ◽

2011 ◽

Vol 368-373 ◽

pp. 1482-1486

Author(s):

Yan Hui Song ◽

Ying Wang ◽

Min Qi Huang

Keyword(s):

Shear Strength ◽

Water Level ◽

Slip Band ◽

Water Pressure ◽

Work Conditions ◽

Stability Factor ◽

Reservoir Water ◽

Reservoir Water Level ◽

Stability Calculation ◽

The Stability

Engineering geology characteristics of No. 7 landslide located at Ciha Gorge is described and shear strength of the slip band soils is determined. Based on the above, unbalanced pushing force method is used to calculate the stability factor of the landslide the under different work conditions. It shows that the influence of the reservoir water level rising on the No. 7 landslide mainly includes two points: (1) water makes the shear strength of slip band soils reduced and thus result in the reduction of the stability factor; (2) the rising of reservoir water level also exerts water pressure to the surface of landslide body, and this is beneficial to landslide stability. Calculation results show that with the rising of reservoir water level the stability factor will experience beginning’s reducing followed by later increasing. The minimum stability factor in the process of impounding is 1.05 and it will be 1.08 when reservoir water level reaches to normal impounded level. This shows that No. 7 landslide will maintain elemental stability status in the all process of impounding.

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