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River Quaggy Case Study Geography

River management case studies

HARD Engineering in the Mississppi
  • The US needed to prevent the yearly floods and tame the river to make it navigable in order to develop
  • Before management schemes were implemented the river constantly shifted its channel and eroded its banks
  • They used stone dykes to trap sediment and provoke the river to erode vertically so that the channel was deep enough for paddle steam boats to use
  • More wing dykes were constructed along with reserviors, levees and channel straightening, channelisation (concrete matressing) and dregding were also used -----> this all made the river faster as they increased the gradient along the rivers long profile
  • All of this management, like all river management in the America, was completed by the US Army Corps of Engineers and costs $180 million a year in maintainence as the force of the water sweeps away thousands of dollars worth of management each year. It is hard to manage rivers as they constantly change (in a state of dynamic equilbrium) and so management techiniques are based on guess work and trialed in labs. Some people, though, think that management of the Mississippi has made the floods worse......
    • 1993 = 3 months of torrential rain -----> defences were not designed for the such large size of flood that occured and the local people chose not to pay for the levees to be heightened. The levees failed. However, many think that if the levees didn't fail then the flooding would have been worse as they are believed to constrict water movement, block up the channel and increase pressure.
    • Floodplain development has raised the flood risk as concrete increases surface runoff by reducing infiltration. Also the removal of vegetation reduces the interception store and, because there is nothing to trap the sediment, can raise the level of the river bank. Drains etc, which are designed to imitate the natural processes like throughflow,are a lot more efficient and so the water enters the channel quicker. Therefore scientists conclude that floodplains should not be built on as they are a natural flood defence that is supposed to flood.
SOFT Engineering in the River Rhine
  • The high flooding of the River Rhine in 1993 and 1995 , in combination with the growing awareness of global climate change, made the public and respective authorities realise that constantly raising the height of levees and dykes, for example, is neither economically or environementally sustainable and that, instead, it is more appropriate to allow the river more room so that it can deal with a higher discharge at a lower water level. This reflects a new philosophy that we should adapt to the shape and behaviour of the river basins nto alter them to suit us. This has been approached by:
    • Landuse change and relocation of habitats - not allowing building developments to be constructed on flood plains as they are supposed to flood
    • Floodplain land use zoning - land is being zoned for uses that will not be damaged by winter floods like forests and parks etc.
    • Afforestation - the planting of trees has increased the interception store, prevented the net movement of sediment and so reduced the amount of water and sediment reaching the river
    • Room for the River scheme which includes:-
      • An increase in water meadows which can be allowed to flood when necessary. The sealing of the soil surface with tarmac or concrete in vulnerable areas is being limited to slow the water run off into the rivers
      • Ground coverage of vegetation with woodlands and grasslands is being increased
      • The use of fertilisers on soil is being carefully monitored because these affect the soil structure and its ability to retain water
      • To allow more space for trees on the floodplain, metres of silt accumulated over many years has been stripped and deep trenches constructed
  • All of these soft engineering methods have increased the time taken for water to enter the channel, reduced the amount of water that does enter the channel, created a channel that has a larger cross section and so can accomodate a larger volume of water and moved people away from the most vulnerable areas - remeber that disasters, like a flood, only occur when people come in close contact with a risk!
  • Some hard management options are still being used though like the building of flood relief channels to siphon off the Rhine flood water when the delta becomes overloaded, making the course of the river straighter and shorter and increasing the height of some of the levees.
SOFT Engineering in the River Quaggy
  • The River Quaggy runs through southeast London and since the 1960's it has been heavily managed by building artifical channels and culverts to divert the flow beneath the surface as it passed through Greenwich.
  • The areas of Lewisham and Greenwich have become more densely populated and the flood risk has increased, due to the continued development, and so more is needed to be done to protect the surroundign area. Further widening and deepening of the channel were considered but instead teh Environment Agency decided a softer option was most appropriate. A solution was proposed by the local residents, who formed the Quaggy Waterways Action Group, that would improve the local environment whilst also provided protection against floods.
  • The plan was to bring the river back above ground once again , cutting a new channel through Sutcliffe Park, and creating a new multi-functional open space. This method improves both the flood management and quality of the park. A culvert did remain to take soem of the excess water, during times of flood, underground but a new lake was built to allow the are to deal with the majority of the excess water when the river floods.
  • The park itself was lowered and shaped to create a new floodplain where watercould naturally collect, instead of rushing downstream through the previous artifical channels to flood Lewishantown centre. The parks flood storage capacity is equivalent to 35 Olympic swimming pools, has reduced the risk of flooding for 600 homes and businesses in the local area and created a diverse environment for wildlife
  • By reducing the river to a more natural course and including a flood storage area, the scheme has created a wetland environment with reedbeds, wildflower meadows and trees. This scheme won the Natural Environment category in the 2007 Waterways Renaissance Awards and the Living Wetland Award.
This is the remainder of the river case studies we need to know for the exam. I don't know if any of you feel the same, but after going through the mock yesterday, I realised that it is so much easier to do well if you know the case studies really well. So next I think I will go through the population case studies as there are rather a lot of them - the population policies and migration case studies are already on here........

Email: g.wharton@qmul.ac.uk
Telephone: +44 (0)20 7882 5439
Room Number: Geography Building, Room 111

Profile

I am a Professor of Physical Geography and a Chartered Geographer (Geomorphology) with over 20 years’ research experience in hydrogeomorphology and hydroecology. My research on rivers focuses on:

  • interactions between water, plants and sediments;
  • entrainment and transport of fine cohesive sediments;
  • river restoration and natural flood management.

Bere Stream at Snatford Bridge is one of my study sites in the Frome-Piddle Catchment, Dorset, UK (photo: G.Wharton).

After completing a BSc Honours degree in Geography at the University of Sheffield and a PhD at Southampton University, I held a Natural Environment Research Council (NERC) Post-Doctoral Research Fellowship before joining the School of Geography at Queen Mary, University of London.

I am currently a member of the NERC Peer Review College, a Subject Editor for the Journal of Soils and Sediments, and a Director of the International Association for Water Sediment Science. Past appointments have included: Chair of the Board of Directors of the UK River Restoration Centre; Honorary Secretary of the Royal Geographical Society with Institute of British Geographers; and Secretary of the Geography Section of the British Association for the Advancement of Science.

Some of my key recent publications are:

  • Grabowski, R. C., Wharton, G., Davies, G. R., & Droppo, I. G. (2012). Spatial and temporal variations in the erosion threshold of fine riverbed sediments. JOURNAL OF SOILS AND SEDIMENTS, 12(7), 1174–1188. doi:10.1007/s11368-012-0534-9
  • Grabowski, R. C., Droppo, I. G., & Wharton, G. (2011). Erodibility of cohesive sediment: The importance of sediment properties. EARTH-SCI REV, 105(3-4), 101-120. doi:10.1016/j.earscirev.2011.01.008
  • Grabowski, R. C., Droppo, I. G., & Wharton, G. (2010). Estimation of critical shear stress from cohesive strength meter-derived erosion thresholds. LIMNOL OCEANOGR-METH, 8, 678–685. doi:10.4319/lom.2010.8.678
  • Heppell, C. M., Wharton, G., Cotton, J. A. C., Bass, J. A. B., & Roberts, S. E. (2009). Sediment storage in the shallow hyporheic of lowland vegetated river reaches. In HYDROLOGICAL PROCESSES Vol. 23 (pp. 2239–2251). doi:10.1002/hyp.7283

Teaching

I teach at all undergraduate levels and I am currently contributing to the following modules:

  • GEG4206 Introduction to Environmental Ideas and Practice
  • GEG5203 Earth System Cycles
  • GEG5211 Research Strategies in Physical Environments
  • GEG6000 Independent Geographical Study
  • GEG6203 Environmental Hazards
  • GEG6212 Project in Environmental Science
  • GEG6218 Integrated Catchment Management

My teaching draws on my empirically-based research on rivers and, through my work in river restoration, students are introduced to current policy and practice in river restoration. Classes are interactive with frequent opportunities for discussion and debate, and site visits to restoration schemes allow students to gain first-hand knowledge of restoration design and develop an appreciation of the challenges and benefits of restoring rivers.

At masters level, I teach modules on:

MSc Integrated Management of Freshwater Environments

  • GEG7304 Catchment Hydrology: Managing Water Resources and Hydrological Extremes
  • GEG7307 Hydrogeomorphology: River and Floodplain Appraisal and Management

MSc Environmental Science by Research 
Current and recent supervisees and projects:

  • Michael Brierley (2012–3): Assessing the impact of stormwater outfalls on the sediment quality of the River Wandle. In collaboration with, and partly-funded by, the Wandle Trust.
  • Rebecca Shears (2008–9): Integrated pre-project appraisal of Mayesbrook Park river restoration scheme. Funded by the Environment Agency.
  • Claire Hulbert (2005–6): Integrated post-project appraisal of an urban river restoration scheme: the River Quaggy, Sutcliffe Park, South East London. Funded by the Environment Agency.

Research

Research Interests:


Submerged aquatic vegetation (Ranunculus sp. / Watercrowfoot) on the River Frome at Maiden Newton, Dorset, UK (photo: G.Wharton)

Interactions between water, plants and sediments in rivers
Many rivers contain aquatic plants growing in the centre of the channel (submerged) and at the margins (emergent) and they act as important ecosystem engineers, modifying flow patterns and the processes of sediment deposition, entrainment and transport (Cotton et al., 2006). Invertebrates (such as blackfly larvae) that live on these plants modify sediment properties, resulting in organic-rich and highly-aggregated fine sediments (Wharton et al., 2006). These are some of the processes that were investigated and quantified as part of the NERC Lowland Catchment Research Thematic Programme (NER/T/S/2001/00932: Fine sediment and nutrient dynamics of lowland permeable streams: establishing the significance of biotic processes for sediment modification). Because contaminants such as fertilisers and pesticides adsorb to fine sediments and the nutrient-rich sediments within the aquatic plants release methane (Sanders et al., 2007) there are implications for river health.  


Measurement of flow velocity on the River Lambourn at Boxford using an Acoustic Doppler Velocimeter (photo: G.Wharton)

The Environment Agency is using these findings, including a knowledge of the sediment habitats associated with different plants (Wharton et al., 2006; Clarke and Wharton, 2001) to develop and refine a software tool called LEAFPACS. The tool helps in the assessment of a river’s ecological status by predicting what plants should be present and comparing this to actual observations.

Another important issue in lowland vegetated rivers is weed cutting, routinely carried out for flood risk management. Current research is being conducted on the River Lambourn (Adam Sutcliffe, CEH NERC Studentship) to measure and model the detailed flow hydraulics following different weed cutting strategies to inform management decisions about the optimum levels of aquatic plant cover.


Excessive fine sediment deposits within a macrophyte stand over a gravel bed affecting river health (photo: L. Baldock)

Entrainment and transport of fine cohesive sediments
In recent decades increased inputs of fine sediments to lowland rivers have resulted in the ingress of silts, clays and sands into gravels, excessive surficial deposits, and elevated levels of sediment-bound contaminants.

Recent research in the Frome-Piddle Catchment, Dorset, (Robert Grabowksi QMUL PhD Studentship) in collaboration with Ian Droppo (Environment Canada) examined the spatial and temporal variations in the erodibility of fine sediment deposits, using a Cohesive Strength Meter (Grabowski et al., 2012). And associated experimental flume work developed a calibration to allow CSM measurements taken in the field to be expressed as critical shear stress values to help further knowledge of entrainment thresholds for fine cohesive sediments (Grabowski et al., 2010) based on an understanding of the physical, biological and chemical factors that determine a sediment’s erodibility (Grabowski et al., 2011). Parallel research (Luke Warren NERC PhD Studentship; Grieg Davies NERC PhD Studentship) focused on quantifying how much fine sediment is transported in vegetated river reaches (Warren et al., 2009) under seasonally changing vegetation cover and how much fine sediment is stored (Heppell et al., 2009). This work is being developed to consider the residence times of fine sediments and sediment-bound contaminants in vegetated rivers. 


Measuring the erodibility of surficial fine cohesive sediments in the field using a Cohesive Strength Meter (photos: R. C. Grabowski).

Publications

For full details, see my online published profiles on ResearcherID and Google Scholar

Selected publications since 2000

  • Wharton, G., Kronvang, B., Ogrinc, N., & Blake, W. H. (2012). Interactions between sediments and water: perspectives on the 12th International Association for Sediment Water Science Symposium. JOURNAL OF SOILS AND SEDIMENTS, 12(10), 1497–1500. doi:10.1007/s11368-012-0606-x
  • Grabowski, R. C., Wharton, G., Davies, G. R., & Droppo, I. G. (2012). Spatial and temporal variations in the erosion threshold of fine riverbed sediments. JOURNAL OF SOILS AND SEDIMENTS, 12(7), 1174–1188. doi:10.1007/s11368-012-0534-9
  • Sgouridis, F., Heppell, C. M., Wharton, G., Lansdown, K., & Trimmer, M. (2011). Denitrification and dissimilatory nitrate reduction to ammonium (DNRA) in a temperate re-connected floodplain.. Water Res, 45(16), 4909–4922. doi:10.1016/j.watres.2011.06.037
  • Grabowski, R. C., Droppo, I. G., & Wharton, G. (2011). Erodibility of cohesive sediment: The importance of sediment properties. EARTH-SCI REV, 105(3-4), 101-120. doi:10.1016/j.earscirev.2011.01.008
  • Grabowski, R. C., Droppo, I. G., & Wharton, G. (2010). Estimation of critical shear stress from cohesive strength meter-derived erosion thresholds. LIMNOL OCEANOGR-METH, 8, 678–685. doi:10.4319/lom.2010.8.678
  • Warren, L. L., Wotton, R. S., Wharton, G., Bass, J. A. B., & Cotton, J. A. (2009). The transport of fine particulate organic matter in vegetated chalk streams. ECOHYDROLOGY, 2(4), 480–491. doi:10.1002/eco.86
  • Heppell, C. M., Wharton, G., Cotton, J. A. C., Bass, J. A. B., & Roberts, S. E. (2009). Sediment storage in the shallow hyporheic of lowland vegetated river reaches. In HYDROLOGICAL PROCESSES Vol. 23 (pp. 2239–2251). doi:10.1002/hyp.7283
  • Sanders, I. A., Heppell, C. M., Cotton, J. A., Wharton, G., Hildrew, A. G., Flowers, E. J., Trimmer, M. (2007). Emission of methane from chalk streams has potential implications for agricultural practices. FRESHWATER BIOL, 52(6), 1176–1186. doi:10.1111/j.1365-2427.2007.01745.x
  • Wharton, G., Cotton, J. A., & Clarke, S. J. (2006). Spatial and temporal variations in the sediment habitat of Ranunculus spp. in lowland chalk streams - implications for ecological status?. Water, Air and Soil Pollution, 6, 393–401. doi:10.1007/s11267-006-9051-4
  • Wharton, G., Cotton, J. A., Wotton, R. S., Bass, J. A. B., Heppell, C. M., Trimmer, M., Warren, L. L. (2006). Macrophytes and suspension-feeding invertebrates modify flows and fine sediments in the Frome and Piddle catchments, Dorset (UK). J HYDROL, 330(1–2), 171–184. doi:10.1016/j.jhydrol.2006.04.034
  • Cotton, J. A., Wharton, G., Bass, J. A. B., Heppell, C. M., & Wotton, R. S. (2006). The effects of seasonal changes to in-stream vegetation cover on patterns of flow and accumulation of sediment. GEOMORPHOLOGY, 77(3–4), 320–334. doi:10.1016/j.geomorph.2006.01.010
  • Wharton, G., & Gilvear, D. J. (2006). River restoration: meeting the needs of both the EU Water Framework Directive and flood defence?. International Journal of River Basin Management, 5, 1–12.
  • Clarke, S. J., Bruce-Burgess, L., & Wharton, G. (2003). Linking form and function: towards an eco-hydromorphic approach to sustainable river restoration. AQUAT CONSERV, 13(5), 439–450. doi:10.1002/aqc.591
  • Clarke, S. J., & Wharton, G. (2001). Sediment nutrient characteristics and aquatic macrophytes in lowland English rivers. SCIENCE OF THE TOTAL ENVIRONMENT, 266(1–3), 103–112.

PhD Supervision

Postgraduate research opportunities in Earth Surface Science

Current PhD Students (with source of funding)

  • Adam Sutcliffe (NERC CEH Studentship) Effects of seasonal plant growth and weed cutting regimes on river flow hydraulics. Supervisors: Dr P Rameshwaran (CEH, Wallingford), Dr P Naden (CEH, Wallingford), Dr G Wharton (QMUL).
  •  Matthew Cashman (Erasmus Mundus PhD Studentship) Hydromorphological and ecological responses to habitat heterogeneity and large wood. Supervisors: Dr G Harvey (QMUL), Dr G Wharton (QMUL), Dr M Pusch (IGB).
  • Francesca Pilotto (Erasmus Mundus PhD Studentship) River channel response to changes in wood and sediment load: woody debris as a trigger for invertebrate habitat diversity in lowland rivers. Supervisors: Dr Martin Pusch (IBG), Dr G Harvey (QMUL), Dr G Wharton (QMUL).
  • Seyed Hossein Mohajeri (Erasmus Mundus PhD Studentship) Experimental study of the effects of colmation in a gravel bed in a free surface flow. Supervisors: Dr M Righetti (UniTN), Dr G Wharton (QMUL), Professor V Nikora (University of Aberdeen).
  • Tesfaye Haimonot Tarekegn (Erasmus Mundus PhD Studentship) Environmental impacts of river impoundments: reservoir and watershed sediment management. Supervisors: Dr.M Toffolon (UniTN), Dr M Righetti (UniTN), Dr G Wharton (QMUL) .
  • Sepideh Ramezani (Erasmus Mundus PhD Studentship) Nutrient dynamics and hydrological connectivity in agricultural floodplains. Professor A Bellin (UniTN), Dr C M Heppell (QMUL), Dr D Tonina (University of Idaho), Dr G Wharton (QMUL).
  • Mahdi Khademishamami (Erasmus Mundus PhD Studentship) Effects of colmation on fine sediment dynamics in gravel-bed rivers. Supervisors: Professor A Armanini (UniTN), Dr M Righetti (UniTN), Dr G Wharton (QMUL), Professor J Brasington (QMUL).
  • Stuart Smith (part-time, self-funding). Defining environmental flows in modified rivers. Supervisors: Dr G Harvey (QMUL) and Dr G Wharton (QMUL).
  • 2013-16: co-supervisor of two PhD students as part of the Marie Curie International Training Network with the University of Lyon and gIR Engineering, Germany.

Former PhD students (with date of award and source of funding)

  • Helen Dangerfield (2000; College studentship) A study of channel geometry-discharge relationships in semi-natural British rivers as a basis for river restoration.
  • Stewart Clarke (2000; College Studentship and Environment Agency) Macrophyte-sediment interactions in British rivers.
  • Lydia Bruce-Burgess (2004; NERC-ESRC Interdisciplinary Studentship CASE with the Environment Agency) Evaluation of river restoration appraisal procedures.
  • Marta Timoncini (2004; College Studentship) Detection of soil moisture under changing vegetation cover from ERS-2 SAR satellite imagery.
  • Luke Warren (2006; NERC Studentship LOCAR Thematic Programme) The biogenic transformation of fine sediments in lowland permeable catchments.
  • Fotis Sgouridis (2010; College studentship awarded to Geography and SBCS) Nitrate dynamics in a re-connected river floodplain system: the River Cole, Wiltshire, UK).
  • Robert Grabowski (2011; College studentship) The erodibility of fine sediment deposits in lowland chalk streams.
  • Grieg Davies (2012; NERC studentship). The transport of fine sediments in vegetated chalk streams.

Former students have been successful in gaining employment in research (QMUL, Open University, Keele University), the water industry (Southern Water), and environmental consultancies and agencies (Environment Agency, Natural England, Babtie, Royal Haskoning, National Trust, APEM).

I would be pleased to discuss developing research projects in my main areas of expertise. Please refer to the PhD applicants page for information on the application process. You may also wish to consider the EU Erasmus Mundus Joint Doctoral programme, SMART (Science for Management of Rivers and their Tidal Systems). Details on this programme can be found at: www.riverscience.eu

Public Engagement


Sutcliffe Park, River Quaggy, South East London. Post-project appraisals have documented changes in river morphology, macrophyte cover, sediment and water quality (photo: G.Wharton).

River restoration and natural flood management
I have a keen interest in the restoration of urban rivers and have conducted several appraisals of river restoration projects in the Thames catchment, funded by the Environment Agency, and resulting in R&D reports (see below). Over the past 13 years, I have also been closely involved in river restoration in an advisory capacity through my work as a Director and Chair of the UK River River Restoration Centre. Currently, I am working with Professor Angela Gurnell to develop the Urban River Survey  for application by the Environment Agency’s National Environment Assessment Service (NEAS).

R&D Reports


  • Mayes Brook, Barking, East London. Pre and post project appraisals have focused on the water and sediment quality of this urban river (photo: L. Shuker).
    Wharton, G., Spencer, K., Peel, K., Shears, R. and Tekin, V. (2010) Mayesbrook Park River Restoration Baseline Monitoring: a summary report of the water and sediment quality of Mayes Brook and Mayesbrook Lakes, and the usage of Mayesbrook Park. Environment Agency R&D Technical Report, 8 pp.
  • Hulbert, C. A. V., Wharton, G. and Copas, R. (2009) Integrated Post-Project Appraisal of an Urban River Restoration Scheme: The River Quaggy, Sutcliffe Park, South East London. Environment Agency R&D Report, 80 pp.
  • Wharton, G. (2002) Ingrebourne River Geomorphological Overview. A report to Havering Wildlife Partnership and Land Use Consultants. Commissioned by the River Restoration Centre. March 2002, 6pp.
  • Clarke, S. J. and Wharton, G. (2001) Using macrophytes for the environmental assessment of rivers: the role of sediment nutrients. Environment Agency R&D Technical Report E1-S01/TR, Environment Agency, Bristol, 90 pp.

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