scholarly journals River linking in India: Downstream impacts on water discharge and suspended sediment transport to deltas

Elem Sci Anth ◽  
2018 ◽  
Vol 6 ◽  
Author(s):  
Stephanie A. Higgins ◽  
Irina Overeem ◽  
Kimberly G. Rogers ◽  
Evan A. Kalina
Keyword(s):  
Sediment Transport ◽  
Suspended Sediment ◽  
Water Discharge ◽  
Suspended Load ◽  
Trapping Efficiency ◽  
Future Climate Change ◽  
Suspended Sediment Transport ◽  
Delta Front ◽  
Annual Water ◽  
Annual Water Discharge

To expand agricultural production and address water scarcity, India is moving forward with the National River Linking Project (NRLP), which will connect 44 rivers via 9,600 km of canals. Here, we compile the first complete database of proposed NRLP dams, reservoirs and canals, including operating schedules for Himalayan infrastructure. We evaluate potential NRLP-derived changes to mean annual water discharge for 29 rivers and mean monthly water and sediment discharge for six rivers flowing to five major deltas. Sediment rating curves are used to quantify the impacts of changing water discharge within the rivers, and basin-wide trapping efficiency is established for new reservoirs. Given full implementation of the NRLP, we forecast reductions in annual suspended sediment transport to deltas of 40–85% (Mahanadi), 71–99% (Godavari) and 60–97% (Krishna) due to profound reservoir trapping and peak streamflow reductions. The Ganga before its confluence with the Brahmaputra is projected to experience a 39–75% reduction in annual suspended load. The Brahmaputra before its confluence with the Ganga is projected to experience a 9–25% reduction in suspended load, despite losing only 6% of its annual water flow. We calculate a projected corresponding aggradation decrease for the Ganga-Brahmaputra delta from 3.6 to 2.5 mm y–1, which is a large enough change to drive relative sea-level rise at the delta front. At the remaining four deltas, the NRLP will exacerbate current sediment starvation. We reconstruct the annual water transfer volume proposed for the NRLP to be 245 km3 y–1, higher than previous estimates due to the inclusion of along-canal usage. If completed, the NRLP will transform watershed boundaries, with more than half of the land in India contributing a portion of its runoff to a new mouth. These impacts may have profound environmental and public health implications, particularly in the context of future climate change.

scholarly journals Suspended Sediment Analysis: Case Study of Berounka Sources

Geografie ◽  
1997 ◽  
Vol 102 (2) ◽  
pp. 130-138
Author(s):  
Zdeněk Kliment ◽  
Jan Kopp
Keyword(s):  
Seasonal Variation ◽  
Sediment Transport ◽  
Suspended Sediment ◽  
Inorganic Material ◽  
Suspended Sediments ◽  
Suspended Load ◽  
Suspended Sediment Transport ◽  
Sediment Analysis ◽  
Load Characteristics

The article examines suspended sediment transport in Mže, Radbuza, and Úhlava Rivers over the period 1989-95. Data on suspended sediments was collected at five observing sites. The research has been carried out in collaboration with Czech Hydrometeorological Institute, Plzeň. Apart from the suspended load characteristics also the seasonal variation of suspended sediments, siltation of Hracholusky and České Údolí Lakes, and the share of inorganic material in suspended sediments have been examined.

scholarly journals Hysteresis effects of suspended sediment transport in relation to geomorphic conditions and dominant sediment sources in medium and large rivers of the Russian Arctic

2013 ◽  
Vol 46 (2) ◽  
pp. 232-243 ◽  
Author(s):  
Nikita I. Tananaev
Keyword(s):  
Sediment Transport ◽  
Suspended Sediment ◽  
Large Scale ◽  
Water Discharge ◽  
Sediment Flux ◽  
Large Rivers ◽  
Suspended Sediment Transport ◽  
Russian Arctic ◽  
Sediment Formation ◽  
Arctic Rivers

Preliminary analysis of long-term hydrological data shows that sediment dynamics of Russian Arctic rivers is largely affected by hysteresis effects in relation of water discharge to suspended sediment concentration (SSC). The role of large-scale geomorphic and geocryological conditions in sediment transport is still relatively understudied. This research aims to assess the links between hydrogeomorphology and regularities of sediment formation and movement in Russian Arctic rivers. A dataset containing information on measured water discharges and SSC for 27 gauges on 16 medium and large rivers of the Russian Arctic was used in this research. Clockwise hysteresis is typical during spring events, while in summer counterclockwise and ‘figure eight’ curves are widely observed. The results show that the form of the rating curve can be attributed to the dominant sediment source, dominant channel pattern and, to certain extent, to the cross-section position within the river basin. Seasonality in hysteresis effects reflects the role frozen ground dynamic plays in sediment flux formation. Thus, reaction of permafrost landscapes on the widely observed climate shift should lead to significant changes in sediment transfer systems.

scholarly journals Setting Up of an Experimental Site for the Continuous Monitoring of Water Discharge, Suspended Sediment Transport and Groundwater Levels in a Mediterranean Basin. Results of One Year of Activity

Water ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 3130
Author(s):  
Stefano Giorgio Pagano ◽  
Donato Sollitto ◽  
Marco Colucci ◽  
Davide Prato ◽  
Fabio Milillo ◽  
...  
Keyword(s):  
Surface Water ◽  
Sediment Transport ◽  
Suspended Sediment ◽  
Continuous Monitoring ◽  
Water Discharge ◽  
Suspended Sediment Transport ◽  
Flood Events ◽  
Experimental Site ◽  
Groundwater Levels ◽  
Set Up

The study of suspended sediment transport requires continuous measurement of water discharge to better understand the sediment dynamics. Furthermore, a groundwater monitoring network can support the stream discharge measures, as it reveals how the interactions between surface water and groundwater may affect runoff and consequently sediment transport during flood events. An experimental site for the continuous monitoring of water discharge, suspended sediment transport and groundwater levels was set up in the Carapellotto basin (27.17 km2), which is located in Apulia, Southern Italy. Seven flood events that occurred in the operation timespan were covered with a full record of both water discharge and sediment concentration. Some monitoring problems, largely due to the clogging of the float by mud, suggested to improve the experimental set up. The results show high values of suspended sediments concentration which indicate the sub-basin’s key role in the sediment delivery to the whole river system, while counter-clockwise hysteresis loops are the most frequent due to the basin characteristics. The effects of the interaction between surface water and groundwater are related not only to the flood magnitude but also to the hydrogeological features in the hyporheic zone.

scholarly journals SEDIMENT TRANSPORT FIELD DATA AND NUMERICAL MODELING STUDY TO SUPPORT DREDGE PIT INFILL RATE ESTIMATES

2020 ◽  
pp. 57
Author(s):  
Atilla Bayram ◽  
Sean O'Neil ◽  
Yang Zhang
Keyword(s):  
Sediment Transport ◽  
Suspended Sediment ◽  
Field Data ◽  
Transport Model ◽  
Phase 1 ◽  
Field Measurements ◽  
Suspended Load ◽  
Suspended Sediment Transport ◽  
Sediment Transport Model ◽  
Project Site

Site specific bedload and suspended sediment transport data collected at two test pit locations over a four-day period during April 2015 were analyzed to calibrate a numerical sediment transport model of Cook Inlet, AK. The field data campaign was designed to collect suspended load and bedload field measurements and was carried out in two phases. During Phase 1, both suspended load and bedload measurements were taken at approximately 55 ft water depth. The suspended sediment concentration was observed to be nearly uniform over the water column. Laboratory analysis showed the suspended sediment had an effective grain size of approximately 0.03 mm with 0.005 mm within a 95percent confidence interval. During Phase 2, hydrodynamic, suspended load and bedload measurements were collected over four tidal cycles in the surfzone. A two-dimensional sediment transport model was developed to simulate sediment transport infill rates at the dredged areas of the Project site. The model was calibrated by comparing measured suspended load measurements made at two offshore locations. Calibration results showed that the suspended load transport rate, which is the dominant sediment transport regime in the area, can be predicted accurately at the project site. Based on the calibrated sediment transport model, preliminary annual sediment infill rates were estimated to lie between 1.1 to 1.6 ft/yr at offshore and nearshore locations, respectively, for the presently observed and measured conditions.

scholarly journals Estimating long term sediment yields from sediment core analysis

2010 ◽  
Vol 42 (1) ◽  
pp. 115-126 ◽  
Author(s):  
Patricia Kennie ◽  
Jim Bogen ◽  
Hans Olsen
Keyword(s):  
Sediment Transport ◽  
Suspended Sediment ◽  
Sediment Core ◽  
Water Discharge ◽  
Sediment Cores ◽  
Monitoring Station ◽  
Suspended Sediment Transport ◽  
Core Analysis ◽  
Sediment Yields

Estimating long term sediment yields from sediment core analysis Sediment cores from lakes and reservoirs can be used to estimate sediment yields. In proglacial lakes, the bed sediment typically accumulates as varves, reflecting changes in seasonal and annual sedimentation. This report compares the results from two different methods of measuring suspended sediment transport in a Norwegian glacial river and lake. Sediment yields obtained from a study of sediment cores in the proglacial lake Nigardsvatn along with measurements of the delta topset were compared with a 25-year record of sediment transport based on automatic water sampling and water discharge measurements at a monitoring station at the inflowing river. During the period from 1980 to 2005, analyses of sediment cores taken from the lake bed along with measurements and grain size distribution analysis of the delta indicated that a volume of 175,670 to 202,697 m3 was deposited in the lake Nigardsvatn and corresponding river delta. The year 1980 was selected as a convenient starting point because a large-magnitude flood with a 100-year recurrence interval occurred at the end of 1979, leaving an easily recognizable sediment layer and accurate reference point. Sediment cores were taken at a total of 24 locations throughout the lake and 25 locations in the delta. The densities of the sediment cores were found to vary between 1.3 and 1.5 g/cm3 during the period examined in this study, giving a total suspended sediment load of between 175,670 and 202,697 tons. The measurements carried out at the sediment station in the glacier melt-water river gave a value of 294,800 tons during the same period. A final value of 211,100 tons is calculated from the monitoring station results after deduction of the sediment fraction which passes through the lake without being deposited. This gives a discrepancy between the two methods of 8,403 to 35,430 tons (4-20%). This can be partially attributed to the difficulties of measuring the water discharge in the unstable glacier meltwater river. In conclusion, sediment cores may be used to extrapolate or correct measurements from sediment monitoring stations over longer periods but caution should be made when considering single years.

Cascading processes of the Vaia storm in the italian Rio Cordon mountain catchment 

2021 ◽  
Author(s):  
Giacomo Pellegrini ◽  
Riccardo Rainato ◽  
Lorenzo Martini ◽  
Luca Mao ◽  
Lorenzo Picco
Keyword(s):  
Sediment Transport ◽  
Suspended Sediment ◽  
Forest Cover ◽  
Water Discharge ◽  
Management Strategies ◽  
Dilution Method ◽  
Suspended Sediment Transport ◽  
Mountain Catchment ◽  
Cascading Processes ◽  
Direct Discharge

<p>Mountain basins can be affected by Large Infrequent Disturbances (LIDs) that have the power of changing their forest cover and morphological settings, and supplying high amounts of sediments to river networks. The resulting cascading processes are often underestimated although their understanding would improve river management strategies. The recent improvements in the field of sediment transport monitoring and analysis allow to gather a deeper understanding of these long-lasting and complex chains of processes, especially in mountain streams. This contribution aims at investigating the suspended sediment transport exhibited by two recent (summer-autumn 2020) over-bankfull (> 2.3 m<sup>3</sup>/s) flood events occurred in the Rio Cordon, an alpine basin (5 km<sup>2</sup>) strongly altered by the Vaia storm (October 2018). This LID blew down 139 trees along the main active channel that were removed by local forest operations after the event, leaving exposed banks and increasing the availability of fine sediment. Two water quality sondes were placed upstream and downstream the windthrow affected area (WAA) to monitor the Suspended Sediment Load (SSL) and quantify the contribution of the WAA in supplying sediments. Water discharge and suspended sediment transport were continuously measured by the two instrumentations, while water samples and direct discharge measurements (salt dilution method) were taken to derive rating curves and calibrate the turbidity meters. Results show that the early September 2020 event (Q<sub>max</sub>=2.67 m<sup>3</sup>/s) produced a SSL = 39.27 t and a SSL increase of +5% between the downstream and upstream cross-section. To this, it was also registered a +44% variation of SS maximum concentration (SSC g/l) which can be ascribed to the contribution of the WWA. The event of October 2020 (Q<sub>max</sub>=3.05 m<sup>3</sup>/s) instead, registered a SSL of 179.22 t and a SSL and SSC<sub>max</sub> variation of +334% and +81%, respectively. The preliminary results suggest that the SS is not related to the water discharge but for this reason, further analysis and data collection will be made, also considering rainfall data. However, the ongoing monitoring of this area represents a suitable and promising approach for understanding the cascading processes on the SS dynamics in a mountain basin affected by a LID.</p>

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