Discharge measurements at low-flow partial-record stations in Iowa

2021 ◽

Author(s):

Prashant Birbal ◽

Hazi Azamathulla ◽

Lee Leon ◽

Vikram Kumar ◽

Jerome Hosein

Keyword(s):

Gene Expression ◽

Traditional Method ◽

Gene Expression Programming ◽

Predictive Modelling ◽

Low Flow ◽

Rating Curve ◽

Hydrologic Processes ◽

Absolute Relative Error ◽

Efficient Management ◽

Discharge Measurements

Abstract Modelling the hydrologic processes is an essential tool for the efficient management of water resource systems. Therefore, researchers are consistently developing and improving various predictive/forecasting techniques to accurately represent a river's attributes, even though traditional methods are available. This paper presents the Gene-Expression Programming (GEP) modelling technique to accurately model the stage-discharge relationship for the Arouca River in Trinidad and Tobago using only low flow data. The proposed method uses the stage and associated discharge measurements at one cross-section of the Arouca River. These measurements were used to train the GEP model. The results of the GEP model were also compared to the traditional method of the Stage-Discharge Rating Curve (SRC). Four statistical paraments namely the Pearson's Correlation Coefficient (R), Root Mean Square Error (RMSE), Mean Absolute Relative Error (MARE) and Nash-Sutcliffe efficiency (NSE) were used to evaluate the performance of the GEP model and the SRC method. Overall, the GEP model performed exceptionally well with an R2 of 0.990, RMSE of 0.104, MARE of 0.076 and NSE of 0.957.

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Discharge Measurements In Low Flow Conditions With ADCP Technology – First Experiences In Nepal

Journal of Hydrology and Meteorology ◽

10.3126/jhm.v7i1.5615 ◽

1970 ◽

Vol 7 (1) ◽

pp. 40-48 ◽

Cited By ~ 1

Author(s):

J Merz

Keyword(s):

Cross Sections ◽

Measurement Errors ◽

New Technology ◽

Acoustic Doppler Current Profiler ◽

Low Flow ◽

Accurate Information ◽

Flow Measurements ◽

Low Flows ◽

Current Profiler ◽

Discharge Measurements

Low flows prevail during about nine months of the year in Himalayan rivers as a result of the influence of the monsoon climate. They account for a large portion of the annual water balance and accurate information about these flows is therefore critical for water resources planning, development, management and hydropower design. Issues that occur with the neighbouring country India are often related to low flows and make exact information on low flows a prerequisite for successful transboundary water management. However, reliable and long-term information on low flows are generally not available as most basins are ungauged. In addition low flow measurements are often associated with measurement errors as measurement cross-sections change during the flood season. Changes in measurement cross-sections are natural, but need frequent re-surveying of the sections in order to obtain good quality discharge measurements. This is often done on in-frequent basis and changes between big flood events are not recorded. The equipment used for discharge measurements is rarely recalibrated leading to additional errors. Internationally, in the last two decades river and stream discharge measurements have been improved with the introduction of Acoustic Doppler Current Profiler (ADCP) technology. This new technology for hydrologic data acquirement has so far not been used extensively in the Himalayan region. First experiences with a StreamPro ADCP in Nepal as a part of a technology evaluation confirmed the commonly stated advantages of this technology compared to current-meter measurements, and showed its promising potential for various future applications including the application for accurate low flow measurements. Keywords: Discharge measurement; ADCP; low flowDOI: http://dx.doi.org/10.3126/jhm.v7i1.5615 JHM 2010; 7(1): 40-48

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Low Flow Estimation and Hydrogeology in a Chalk Catchment

Hydrology Research ◽

10.2166/nh.1993.9 ◽

1993 ◽

Vol 24 (5) ◽

pp. 297-308 ◽

Cited By ~ 3

Author(s):

B. Clausen ◽

K. Rømer Rasmussen

Keyword(s):

Numerical Model ◽

Temporal Variation ◽

Low Flow ◽

Spatial And Temporal Variation ◽

Flow Estimation ◽

Ungauged Sites ◽

Regional Hydrogeology ◽

Modelling Studies ◽

The Difference ◽

Discharge Measurements

Procedures to estimate low flow statistics at ungauged sites and their relation to hydrogeology are presented. The discussion is based on an example of a Danish chalk catchment of 242 km2, within which the climatic variation is small compared to the physiographical variation. The spatial and temporal variation of streamflow was studied using synchronous discharge measurements and the application of a numerical model. The synchronous discharge measurements showed the runoff is unequally distributed within the catchment and depends primarily on the regional hydrogeology, but also on the lithology of the valley deposits. The numerical model was used to obtain an understanding of the hydrogeological effect on the temporal variation of the runoff from small subcatchments. This was not possible from the discharge measurements because of the high uncertainty of estimating the difference in flow between two nearby gauging stations. The temporal variation was found to be strongly related to the hydraulic gradient along the river. A knowledge of catchment processes and variability of runoff from modelling studies is shown to assist in low flow estimation.

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Discharge Data Collection and Analysis Strategies in Low Flow Studies

Hydrology Research ◽

10.2166/nh.1995.0011 ◽

1995 ◽

Vol 26 (3) ◽

pp. 191-204 ◽

Cited By ~ 7

Author(s):

B. Clausen

Keyword(s):

Data Collection ◽

Flow Regimes ◽

Low Flow ◽

Flow Paths ◽

Discharge Data ◽

Flow Estimation ◽

Low Flows ◽

Ungauged Sites ◽

Data Collection Strategy ◽

Discharge Measurements

The objective of this paper is to determine the most appropriate data collection strategy and analysis techniques which should be used to assess the low flow regime of a catchment. The data used were: a) synchronous discharge measurements during low flow periods, and b) continuous daily flow records. The analyses based on both types of data were able to distinguish different low flow regimes within a 114 km2 Danish catchment. Despite the limited spatial variation in climate and geomorphology there was a high spatial variability in low flows caused by differences in the lithology of sediments. This demonstrates the difficulties in using simple indices of catchment geology in regional low flow estimation. The results highlight the benefits of using synchronous discharge measurements, both for estimating low flows at ungauged sites, and for understanding groundwater flow paths. Analyses of daily flow records from six gauging stations in the catchment showed that a baseflow index was more useful than the flow duration curve for classifying low flow regimes when only short records were available. The paper illustrates the importance of estimating the uncertainty of discharge measurements when interpreting low flow data.

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