The Impact of Using Water Why is Continuous Sediment Transfer in Reservoirs and Rivers so important for Sustainability in the Water-Energy-Food Nexus?

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1 The Impact of Using Water Why is Continuous Sediment Transfer in Reservoirs and Rivers so important for Sustainability in the Water-Energy-Food Nexus? GWSP WEF Nexus Conference Bonn, Germany, Dr. Dietrich Bartelt, DB Sediments, Germany

DB Sediments GmbH Based on Environmental Know how Founded on 09.03.

ground, project management, renewable energies Management experience, environmental leadership International

2 DB Sediments GmbH Based on Environmental Know how Founded on in Duisburg, Germany Founders experts each with more than 20 years of international utility back ground, project management, renewable energies Management experience, environmental leadership International research programs since 1994 (i.e. 5th EU FWP, ) Innovation Management Environmental Technology Made in Germany Headquarter at Tectrum Technologie Zentrum 2

Global Water Storage Capacity Increasing Loss 7000

3000 2000 1000 Year 1900 1905 1910 1915 1920 1925 1930

1990 1995 2000 2005 2010 2015 2020 2025 2030 2035 2040

(Sedimentation/Siltation) Source: Based on data from

3 Global Water Storage Capacity Increasing Loss 7000 Global Storage Capacity [Billion m³] Year Net Storage Capacity Storage Capacity Lost Capacity (Sedimentation/Siltation) Source: Based on data from Jenzer and Cesare (2005) and GWSP Digital Water Atlas (2008)

4 Global Risk Perception Survey Environmental Risks are most likely and have highest impact Environmental Risks Extreme weather events Natural catastrophes Man-made environmental catastrophes Biodiversity loss and ecosystem collapse Water crises Climate change Source: World Economic Forum; Global Risks Perception Survey ; 4

5 Sediment Mismanagement Increasing Flood Risk Pakistan, Strong Monsoon, August 2010 Source: AG Friedensforschung; 5

6 The Use of Water Impact to the Ecosystem There is more than water that flows in a river The reduction of velocity causes sedimentation and siltation 6

7 The Two Sides of Sedimentation Sediment Surplus upstream / Sediment Deficit downstream 7

Problems without Sediment Example: Sediment deficit River Rhine

000 t/a artificial adding of Sediments about 230.

000 t/a Adding Sediments is expensive 2012: WSA Duisburg 24 Mio.

8 Problems without Sediment Example: Sediment deficit River Rhine Sedimentdeficit D/NL-boarder: about t/a artificial adding of Sediments about t/a Locks Iffezheim: about t/a Adding Sediments is expensive 2012: WSA Duisburg 24 Mio. Source: Alpreserve *, Bundesanstalt für Wasserbau (Koblenz), Hülskens Wasserbau (Wesel) WSA DU, 8

9 Wave Dynamics Qualitative Change with/without Sediment Transport Wave without Sediment Wave with Sediment 9

10 A river is an Eco-system Sediments are an integral part of this system Source: Global Water System Project 10

11 Sediment Deficit Coast Erosion (e.g. Egypt, ) Source: Google Maps (2011)

12 Mississippi River System Decoupling of water and sediment flows Quelle: Meade, R. H. (2010). Sediment Transport and Deposition in Rivers: The Case for Non-Stationarity. In World Bank Group (Ed.): World Bank Document, A REVIEW OF SELECTED HYDROLOGY TOPICS TO SUPPORT BANK OPERATIONS. Papers from the Workshop (pp , Annex)., National Geographics, May

New 1930 2010 Quelle: Don Swenson (2012)

13 Sediment Mismanagement DeathOrlea Threatns to the Delta (eg Mississippi) New Quelle: Don Swenson (2012) The Rise and Disappearance of Southeast Louisiana. hlandloss1.swf

14 ConSedTrans Method System Sensitive Solution - Continuous Transfer of Sediments 14

15 RWE Innogy GmbH Continuous Sediment Management in Olsberg, Germany 15

Suitable equipment System Sensitive Solution automated vessel size

to 15 m manual small dredge vessel - electric driven - depth up to

equipment upon request: - electric or diesel driven - dredging

16 Suitable equipment System Sensitive Solution automated vessel size 1 - diesel driven - electric driven - depth up to 40 m - depth up to 15 m manual small dredge vessel - electric driven - depth up to 8 m dredge vessel size 2 Larger/other/additional and customized equipment upon request: - electric or diesel driven - dredging depth up more than 200 m - unlimited capacity and/or sediment transfer range 16

Risk Analysis Existing and Projected Dams Assessment of the original storage volume - by processing of the original layout of the reservoir Determination of - the lost, silted or sedimented volume of

17 Risk Analysis Existing and Projected Dams Assessment of the original storage volume - by processing of the original layout of the reservoir Determination of - the lost, silted or sedimented volume of the reservoir, - the silting rate of the dam, and - the estimation of the probable dam life, under consideration of the necessary operational range of the reservoir. Furthermore, an analysis will comprise - possible consequences, like the blockage of the bottom outlet of the dams by sliding sediments and - risk of flooding caused by the reduction of the retention volume of the reservoir. 17

18 Roseau Reservoir St. Lucia Risk Analysis / Rehabilitation Dam/Reservoir 18

19 Nurek Dam, Tajikistan Site, Sedimenttransport 19

20 The new process spends multiple benefit Positive environmental effects: The process restores (and improves) natural river morphology. Sediment in Flow. It is environmentally and fish friendly. Keep quality and level of groundwater. Biodiversity in the river and in the coastal areas of the oceans.

21 The new process spends multiple benefit. Positive operational and economical effects: The reservoir can be used completely again. avoid enormous dump costs and/or avoid generation losses. Reduction of flood risk

22 Final Remarks Dramatic developing decrease of global storage capacity for water The River is an Ecosystem - Sediments are an important part of the system There is an urgent need for a holistic sediment management in rivers and reservoirs Proper Flood Management needs Proper Sediment Management The impact of using water can be compensated by continuous sediment transport There is no economic solution without an ecological solution The ConSedTrans- Method can contribute to handle the risk of sedimentation and siltation, flooding, soil and coast erosion, and saltation of groundwater

If you cut the transport of sediment in a river you kill

Bonn, Germany, 15.11.2011 DB Sediments GmbH Bismarckstr.

23 If you cut the transport of sediment in a river you kill life in the river, as well as in the delta area of the river in the ocean. Juan Pablo Orrego Silva, Alternative Nobel Prize Winner, Bonn, Germany, DB Sediments GmbH Bismarckstr. 142 D Duisburg, Germany T F info@db-sediments.com

24 24

influence factors: rock/ground type precipitation level and intensity vegetation type and condition

25 Basics Solids/Sediment intrusion into water bodies explanation: ungrazed bush, forest land loss by erosion in tons per ha (hectare) grasslands, meadows surface flow in % of precipitation sorghum Major influence factors: rock/ground type precipitation level and intensity vegetation type and condition surface slope bald fallow land Source : Alpreserve, Wilhelm Bechteler: Sedimentationsquellen und Transportprozesse

26 Flowspeed in cm/s Basics Hjulström-Diagram Grainsize in mm 26

The Two Sides of Sediment Within the Reservoir: Sediment Surplus Sediment accumulation in reservoirs leads to: reduced flood protection reduced storage capacity for hydro power peaking/seasonal

27 The Two Sides of Sediment Within the Reservoir: Sediment Surplus Sediment accumulation in reservoirs leads to: reduced flood protection reduced storage capacity for hydro power peaking/seasonal storage Picture: Süddeutsche Zeitung , reduced storage for irrigation / drinking water supply reduced biodiversity inside the reservoir (and i.e. higher temperatures, less oxygen) WCD / ICOLD state that sedimentation in reservoirs exceeds the actual new build of reservoirs. Every year almost 1 % of worldwide storage volume is lost. 20 % of all reservoirs will be inoperable by sediment management is an urgent issue 27

28 The Two Sides of Sediment Downstream: Sediment Deficit Missing sediment/changed morphology downstream of reservoirs cause:... riverbed and bank erosion... foundation failure of civil hydro structures agricultural substrate deficit change of aquatic ecosystem... methane emissions from impounded rivers re-infiltration of saltwater into groundwater at river delta/coastline coastline erosion Replacement of missing sediment is costly (e.g. Colorado, Rhine) 28

29 Present solutions Attempts that cause negative effects 1. Reservoir flushing by opening the base outlet applicable when sedimentation reaches the dam effective only for area near to outlet loss of tremendous amounts of water and power production strong negative ecological effects downstream 2. Manual dredging usually plant offline for some months enormous dump cost reservoirs benthos structure destroyed further erosion downstream 3. Dredging campaign with disposal downstream requires large amounts of propulsion water destroys benthos structure up- and downstream short term sediment surplus downstream 29

30 Flushing of a Reservoir Langmannsperre, Austria,

Built in 1995; H=40 m Drinking Water Supply, Flood Protection Storage Capacity

31 Roseau Reservoir, St. Lucia Function and Purpose John Compton Dam is a concrete faced rockfill dam Built in 1995; H=40 m Drinking Water Supply, Flood Protection Storage Capacity 3.0 Mio m³ (2014 over 1.0 Mio. m³ lost through sedimentation/siltation) Mono-Use due to missing regulation besides drinking water pumps)

32 Risk Analysis Bathymetric Survey Water Depth 32

33 Risk Analysis Bathymetric Survey - Sediment Thickness ( ) 33

34 Risk Analysis Sediment Volume - Allocation per Section (50 m each) 34

up to 250-450 m³/h - High solid content Discharge distance up to 600m Working

35 ConSedTrans Method Remote Controlled Dredgers Winches for mooring an positioning Safer because no humans are needed onto the barge Pump capacity up to m³/h - High solid content Discharge distance up to 600m Working depth up to 35m Power 100 HP Delivery pipe diameter 200 mm (8 ) Solids passage 60 mm 35

ConSedTrans Method Continuous Sediment Transfer A way to overcome the problem of Sedimentation

ConSedTrans Method Continuous Sediment Transfer A way to overcome the problem of Sedimentation German American Chambers of Commerce Round Table, Milwaukee, USA, 30.10.2013 Dr. Dietrich Bartelt, DB Sediments,