ri ver restoration centre 18 annual network conference...eric gillies (cbec eco-engineering)...
TRANSCRIPT
River Restoration Centre
18th Annual Network Conference River Restoration: Addressing Uncertainty
4th – 5th April 2017 – The Hilton Metropole Hotel, Brighton
Kindly sponsored by:
Abstracts
2018
RIVER RESTORATION CENTRE 19TH ANNUAL NETWORK CONFERENCE
"Engaging with Rivers" 24th and 25th April 2018 – EMCC, Nottingham
PROGRAMME OF EVENTS
DAY 1: - - - TUESDAY 24TH APRIL - - -
09:00
REGISTRATION at Reception Opens at 08:30
NETWORKING & EARLY VIEWING POSTER SESSION
in the Exhibition Hall
60 mins
Session 1 Conference Theatre
CHAIR: Martin Janes (the River Restoration Centre)
10:00 River Restoration Centre introduction & welcome Martin Janes (the River Restoration Centre)
15 mins
10:15 Engaging with rivers - restoration in Scotland and New South Wales - a tale of two Tweeds Chris Spray (University of Dundee)
15 mins
10:30 A partnership approach to misconnections in London: the ‘outfall safari’ two years on Joe Pecorelli (The Zoological Society of London)
15 mins
10:45 Discussion 15 mins
11:00 SHORT BREAK with coffee and tea 35 mins
11:35 Handing over design of a major flood relief channel and its surrounds to stakeholders – did it make a difference? Vicky Lutyens (Black & Veatch)
15 mins
11:50 Natural Flood Management: Shaping success through Partnerships Jenny Broomby (JBA Consulting)
15 mins
12:05
Infrastructure development: Opportunities and challenges for managing rivers and their catchments Tom Styles & Oana Iacob (Arup)
15 mins
12:20 Discussion 15 mins
12:35 LUNCH in the Exhibition Hall 60 mins
RIVER RESTORATION CENTRE 19TH ANNUAL NETWORK CONFERENCE
"Engaging with Rivers" 24th and 25th April 2018 – EMCC, Nottingham
Session 2
Conference Theatre
Natural Flood Management in Practice
Conference Suite 2
Evidencing Change
Conference Suite 3
Barriers
CHAIR: TBA CHAIR: David Harper (Welland Rivers Trust) CHAIR: Andrew Kerr (the Sustainable Eel
Group)
13:35
NFM: Delivering multiple benefits through Flood Risk Management Alex Fraser (Jacobs) & Sim Reaney (Durham University)
Evaluating river restoration techniques: Settlement ponds in the Afon Eden catchment, North Wales Sue Hearn (Natural Resources Wales) & Heather Marples (Bangor University)
Novel design, installation and assessment of coarse fish passage using Low Cost Baffle (LCB) solution at a gauging station Toby Hull (South East Rivers Trust)
15 mins
13:50
Reducing Flood Risk through Green Infrastructure on the River Soar, Leicester Alex McDonald (Environment Agency)
The Rottal Burn restoration project: Collaborative evidence and impact from River Champions, Research Collaborators (and lots of student projects) Rebecca Wade (Abertay University) & Kelly Ann Dempsey (River South Esk Catchment Partnership)
The impact of weir removal on the foraging and activity of British Bats Sarah Scott (Environment Agency)
15 mins
14:05
Discussion
Discussion
Discussion 10 mins
RIVER RESTORATION CENTRE 19TH ANNUAL NETWORK CONFERENCE
"Engaging with Rivers" 24th and 25th April 2018 – EMCC, Nottingham
Session 2 – continued…
14:15
Prioritising restoration and NFM in the River Peffery, Scotland Emma Lewin (Jacobs)
Implementing Flood Risk Management and river restoration to conserve instream habitat for brown trout Natalie Angelopoulos (University of Hull)
New guide to fish passage and screening at Flood Risk Management and land drainage structures based on practical experience Omar Sholi (AECOM)
15 mins
14:30
Do we need an NFM reality check? Eric Gillies (cbec eco-engineering)
Engaging with rivers in four dimensions Lucy Shuker (Thames 21/Cartographer Studios Ltd)
Approaching 10 years on - shedding light on stream daylighting around the world Adam Broadhead (Arup)
15 mins
14:45
Discussion
Discussion
Discussion
10 mins
14:55
POSTER SESSION in the Exhibition Hall with tea and coffee
Vote for your top poster (not just your friends!)
45 mins
RIVER RESTORATION CENTRE 19TH ANNUAL NETWORK CONFERENCE
"Engaging with Rivers" 24th and 25th April 2018 – EMCC, Nottingham
Session 3
Conference Theatre
Working in Partnership
Conference Suite 2 Managing Sediment
and Pollutants
Conference Suite 3 Novel ways of
using Data
CHAIR: TBA
CHAIR: TBA CHAIR: TBA
15:40
Better Together - How working in partnerships has achieved so much more in Telford's urban catchment Guy Pluckwell (Environment Agency)
Contaminated sediment: Assessing risks in UK rivers Ian Dennis (Royal HaskoningDHV)
Historical studies for informing sustainable river restoration strategies Jennifer Cox (Ricardo/University of Portsmouth)
15 mins
15:55
Towards a wilder River Crane: Benefits of partnership delivery Tom White (London Wildlife Trust)
Managing accumulated sediments: Beneficial Use of Dredged Material (BUDM) and Working with Nature (WwN) William Manning (Exo Environmental)
Simple mapping for flood risk and storage Marc Naura (the River Restoration Centre) 15 mins
16:10
Discussion
Discussion
Discussion
10 mins
RIVER RESTORATION CENTRE 19TH ANNUAL NETWORK CONFERENCE
"Engaging with Rivers" 24th and 25th April 2018 – EMCC, Nottingham
Session 3 – continued…
16:20
Living Heritage of the River Don Rachel Walker (Don Catchment Rivers Trust)
Silt management can be easy... why are so many people getting it wrong? Richard Haine (frog environmental)
CatMan: A Natural Capital framework based on whole catchment modelling of land use, asset improvement, diffuse pollution and flood risk Rachelle Ngai (JBA Consulting)
15 mins
16:35
‘Smarter Water Catchments’ in the Evenlode - working in partnership to reduce phosphorus in rivers Jonathan Westlake (Thames Water)
Partnership working in the Sussex Ouse catchment Simon Lohrey (South East Water) & Emily Long (National Trust)
Community Modelling – Shaping the future of London rivers Rosie Nelson (Thames 21)
15 mins
16:50 Discussion Discussion Discussion 10 mins
17:00 SHORT BREAK TO MOVE TO KEYNOTE SESSION 10 mins
RIVER RESTORATION CENTRE 19TH ANNUAL NETWORK CONFERENCE
"Engaging with Rivers" 24th and 25th April 2018 – EMCC, Nottingham
Session 4
Conference Theatre
CHAIR: TBA
17:10 Keynote address – Natural Capital Paul Leinster, Professor of Environmental Assessment, Cranfield University
25 mins
17:35 Questions and reflections 20 mins
17:55 Poster competition prizes, final announcements and close Martin Janes (the River Restoration Centre)
5 mins
18:00 END OF DAY 1
19:30 – PRE-DINNER DRINKS RECEPTION
Entrance Foyer &
20:00 – UK RIVER PRIZE AWARDS DINNER Banqueting Suite
RIVER RESTORATION CENTRE 19TH ANNUAL NETWORK CONFERENCE
"Engaging with Rivers" 24th and 25th April 2018 – EMCC, Nottingham
DAY 2: - - - WEDNESDAY 25TH APRIL - - -
Registration Opens at 8:30 am
Session 5
9:00 CHOICE OF ONE SITE VISIT OR ONE WORKSHOP 3 h 30 min
Workshop A: A Focus on Floodplains
Key players in floodplain degradation Seb Bentley & George Heritage (AECOM)
Multi-objective floodplain restoration from California, USA Chris Bowles (cbec eco-engineering)
High impact river and floodplain restoration of the Hampshire Avon near Upavon Martijn Antheunisse (Wiltshire Wildlife Trust)
Workshop B: Large Wood in Rivers
The Influence of Large Woody Dams on Sediment Dynamics Matthew McParland (University of Liverpool)
The impact of wood on benthic and hyporheic invertebrates. Chiara Magliozzi (Cranfield University)
Practical Aspects of Using Large Wood in River Restoration & Channel Management David Holland (Salix)
Workshop C: River Restoration for Biodiversity
Restoring Freshwater Mussel Rivers Ceri Gibson (Freshwater Biological Association)
Understanding Historic Change and Using Natural Processes to Inform Future Decision Making Matthew Hemsworth (JBA Consulting)
Workshop D: Natural Capital and Ecosystem Services:
Accounting for Benefits Monetising environmental benefits – three case studies Angus Pettit (JBA Consulting)
What have wetlands ever done for us? David Gasca (Atkins
Workshop E: Managing Sediment already in Rivers
Site visit 1: TBA
Site visit 2: TBA
12:30 LUNCH 65 mins
RIVER RESTORATION CENTRE 19TH ANNUAL NETWORK CONFERENCE
"Engaging with Rivers" 24th and 25th April 2018 – EMCC, Nottingham
Session 6
Conference Theatre
Natural Processes and Morphological Adjustment
Conference Suite 2
Approaches to Planning and Implementation
Conference Suite 3
Catchment Scale Thinking
CHAIR: TBA CHAIR: TBA CHAIR: TBA
13:35
The importance of decadal scale morphological change in flood risk management - The Cashen Estuary, County Kerry Claire Barrett-Mold (Black & Veatch)
River Restoration Wipeout Simon Whitton & Di Hammond (Affinity Water)
Improving natural functioning at the catchment scale Louise Webb (Natural England)
15 mins
13:50
Let the river erode! Giving a gravel-bed river back its freedom space… what do you get? Richard Williams (University of Glasgow)
Alien invaders ahead! - Are you watching out for them? Phil Aldous (Thomson Ecology Ltd)
Riverlands - Exploring people's connections to rivers as a catalyst for change Richard Higgs (National Trust)
15 mins
14:05
Discussion
Discussion
Discussion 10 mins
RIVER RESTORATION CENTRE 19TH ANNUAL NETWORK CONFERENCE
"Engaging with Rivers" 24th and 25th April 2018 – EMCC, Nottingham
Session 6 – continued…
14:15
Sediment and Managed Naturalisation: Results from the Monitoring of Swindale Beck George Heritage (AECOM)
South Calder Water - Challenges in Urban River Restoration Chris Pittner (Peter Brett Associates)
Are we achieving integrated catchment management in practice? Ed Rollason (Durham University)
15 mins
14:30
How do we properly implement the process-based river restoration approach? Hamish Moir (cbec eco-engineering)
Erosion Risk Screening in Engineering Design on Major Infrastructure Projects Helena Parsons (Jacobs)
Network topology: the "missing link" in understanding catchment controls on instream habitats? Eleanore Heasley (Kings College London)
15 mins
14:45 Discussion Discussion Discussion 10 mins
14:55 MOVE TO GRAND FINALE! 10 mins
11
RIVER RESTORATION CENTRE 19TH ANNUAL NETWORK CONFERENCE
"Engaging with Rivers" 24th and 25th April 2018 – EMCC, Nottingham
Session 7
Conference Theatre
CHAIR: TBA
15:05 10 Minute Wake-up and Provocation 10 mins
15:15 Incised lowland sand-bed streams in the Netherlands Christian Huising & Maarten Veldhuis (Waterboard Vallei en Veluwe) 15 mins
15:30
Recreating anastomosing streams to restore channel-floodplain connectivity and recover lost habitats and ecosystem services, Mid-West, USA Colin Thorne & Janine Castro (University of Nottingham)
15mins
15:45 Restoring UK catchment scale biodiversity - rivers, lakes, ponds and wetlands Stewart Clarke (National Trust)
15 mins
16:00 Questions, Thoughts and Parting Insights 30 mins
16:30 END OF CONFERENCE
with tea and coffee
Day1: Tuesday 24th April
Session 1: Conference Theatre
ENGAGING WITH RIVERS - RESTORATION PRIORITIES IN SCOTLAND AND NEW SOUTH WALES - A TALE OF TWO TWEEDS
C. SPRAY1, L. COMINS2, D. ROBESON2 & T. ALLETSON3 1 University of Dundee, 2 Tweed Forum, 3 Tweed Shire Council, New South Wales
On the face of it, the Tweed in the Scottish Borders and the Tweed in New South Wales might
be expected to have little in common, other than possible ancient claims of historic
connectivity. However, what began as an idle moment of web-based curiosity has developed
in to a real partnership between two key organisations involved in promoting and
implementing sustainable management of their respective catchments over 16,000 km apart.
Growing realisation that Tweed Shire Council in New South Wales (NSW) and Tweed Forum
in Scotland shared many challenges when it came to river and catchment management was
further strengthened by discovery that they had both developed innovative approaches to
meeting them. This led to further communication and, eventually to two visits to Australia
hosted by Tweed Shire Council (Tom Alletson) - in 2016 (Derek Robeson) and 2017 (Luke
Comins and Chris Spray).
In this presentation we report on the comparative river management challenges facing the
local communities and institutions in the two locations. We explore the importance of
stakeholder engagement and the different governance mechanisms in place, we describe the
approaches developed towards river restoration and we showcase examples of action on the
ground in Australia and Scotland.
The dominant land uses of the two Tweed catchments, present and past, frame the current
approaches to river management and restoration initiatives. Forestry and farming, especially
sugar cane (NSW), sheep and barley (Scotland) are important drivers when it comes to
decision-making on river management. Whilst flood risk has always been part of the
background to decisions on farming practices and indeed settlement locations, recently the
increasing threats of major floods has added a new dimension to thoughts of catchment
management and flood risk reduction. At the same time, the loss of riverine biodiversity is
becoming ever more apparent, alongside the encroachment of invasive non-native species.
Challenges of economic and agricultural productivity remain, as does the need to engage with
local communities in the development of solutions.
We describe the development of approaches by the two organisations to increased
stakeholder engagement across different facets of river life and management. We place river
restoration centrally in this discussion, drawing out comparative barriers and solutions from
the two locations, with examples of ongoing programmes and successes in each catchment.
Finally, we look at what general lessons could be learned by others from our experiences.
A PARTNERSHIP APPROACH TO MISCONNECTIONS IN LONDON: THE ‘OUTFALL SAFARI’ TWO YEARS ON
J. PECORELLI1 & J. BRYDEN2 1 The Zoological Society of London, 2 Thames21
Within the Greater London Authority boundary there are 600km of rivers and stream
comprising of 39 rivers, of which, so far, only one has been classified as achieving ‘good’
ecological potential under the Water Framework Directive.
One of the major threats to water quality in these rivers is misconnections that send foul
waste to rivers via the surface water drainage system. Misconnections have been cited by the
Environment Agency as one of the reasons for waterbodies in London not achieving “good”
ecological status (or potential) and could contribute to failing phosphate levels. This is not the
only way that surface water outfalls convey pollution to our rivers. Blockages in the foul
sewers, caused for example by a build-up of fat or wet wipes, can also pollute rivers by causing
foul wastewater to back up in the sewers and drain into the surface water network and then
to rivers. Poorly designed or dilapidated sewer infrastructure can also allow foul waste to
enter surface water pipes.
In recent years, there has been no systematic surveying of outfalls to identify and report
pollution problems to the Environment Agency and Thames Water. ZSL, working in
partnership with fellow NGO’s, Thames Water, the Environment Agency and communities
across London, has developed an innovative, citizen science technique for locating, reporting
and prioritising polluted outfalls and gathering further evidence on the scale of the problem.
Known as the Outfall Safari, the survey method is devised to fill the evidence gathering and
reporting gap. An Outfall Safari involves training teams of volunteers how to assess outfalls
for pollution. Once trained, volunteers conduct coordinated surveys, walking the riverbanks
in groups, armed with a specially created app that allows them to geolocate, photograph and
assess outfalls for evidence of pollution, including sewage fungus, sanitary products and
discoloured water.
Between May 2016 and November 2017, 142km of river were surveyed in Greater London
and 1,177 outfalls assessed of which 356 showed signs of pollution.
Thames Water is responsible for the majority of outfalls in Greater London; the remainder are
Highways Agency, Local Authority or privately owned. This presentation will show the findings
of the Outfall Safaris, the response by Thames Water and other stakeholders to the data
generated and how the method has been adapted and applied to other catchments outside
London. We will also present thoughts on what other measures need to be adopted to tackle
misconnections, a serious problem that blights urban rivers across the UK.
For more information, www.zsl.org/londons-rivers
HANDING OVER DESIGN OF A MAJOR FLOOD RELIEF CHANNEL AND ITS SURROUNDS TO STAKEHOLDERS – DID IT MAKE A DIFFERENCE?
V. LUTYENS1 1 Black & Veatch
The River Thames Scheme (Datchet to Teddington) is one of the UKs largest flood risk
management schemes of recent years. It will reduce flood risk to 15,000 homes and
businesses and involves construction of a 17km long major flood relief channel through west
London plus associated measures. Black & Veatch is leading outline design for the
Environment Agency and partners.
A deliberative approach was adopted to engage with the wide variety of stakeholders,
including authorities, user groups, conservation bodies and landowners. This paper discusses
how, through a series of meetings, stakeholders suggested 100s of enhancement
opportunities that were captured in the design of the channel and surrounding landscape. It
will summarise how: a) design suggestions from stakeholders were incorporated and shaped
a vision that linked the history of the River Thames with the functionality of the scheme; b)
consultees were able to influence areas of uncertainty.
Specific examples will be shown of design areas that were influenced by engagement, in
particular:
Channel alignment in areas of design uncertainty (including at sites of high nature
conservation importance and archaeological sensitivity)
10km of new public access adjacent to the proposed channel
The four large-scale Landscape Enhancement Areas, and their ‘beacon concept’ providing
long range views across the floodplain
The 100 ha+ of water dependant habitat creation at two large sites
The presentation will conclude by summarising some of the challenges faced in opening
up design to multiple voices (technical, legal, and financial), and the next steps in taking
forward proposals
NATURAL FLOOD MANAGEMENT: SHAPING SUCCESS THROUGH PARTNERSHIPS
J. BROOMBY1 1 JBA Consulting & University of Leeds
The recent paradigm shift away from traditional flood defence to more holistic approaches
such as natural flood management (NFM) and catchment management has stimulated a
discussion regarding the means by which such measures can be successfully implemented.
Working with Natural Processes (WWNP), defined by the Environment Agency as “taking
action to manage fluvial and coastal flood and coastal erosion risk by protecting, restoring
and emulating the natural regulating function of catchments, rivers, floodplains and coasts”,
often requires work across whole catchment areas as well as across a wide set of participants
and skills. Partnerships are increasingly seen as a necessary method of tackling complex,
multi-level and multi-scalar issues, such as flooding, catchment management, habitat
enhancement and river restoration.
This study explored partnership working in WWNP schemes across the UK, focusing on the
factors that impact and shape success, drawing awareness to their experiences and allowing
future partnerships to learn from past projects. Whilst the role of individual contexts is
important to consider, there were a number of commonalities identified across 60 NFM
documented case studies, including schemes such as Holnicote, Pickering, Haweswater,
Belford, Blackbrook, Stroud Rural SuDS and Haltwhistle, which could provide valuable
guidance for future NFM partnerships and initiatives.
Local communities, landownership and the evidence gap are examples of factors that can
both drive a partnership as well as act as a barrier to progress. Other factors that drive and
enable the creation of partnerships are project champions; pre-existing relationships
between partner organisations; a common vision; local organisations; authorities and
democratically-elected project officials; the use of trial catchments; and the role of neutral
agents such as NGOs and academic institutions. In addition, during a partnership, the
incorporation of local knowledge, clear governance structures and a common vision between
partners further contribute to the success of the project overall. These factors determine the
levels of proximity within a partnership, which, in its 6 different forms (physical, spatial,
institutional, social, technological and relational), is crucial to the success of a project and
must be addressed both prior to and during a partnership to ensure as smooth and equitable
a process as possible.
The application of partnership working to NFM is relatively recent and unique, with little
academic research conducted to date. This work provides some practical guidance to NFM
and river restoration initiatives as well as contributing to this burgeoning area of research.
INFRASTRUCTURE DEVELOPMENT: OPPORTUNITIES AND CHALLENGES FOR
MANAGING RIVERS AND THEIR CATCHMENTS
T. STYLES1 & O. IACOB1
1 Arup
Flagship river and catchment management projects in the UK are typically focused on
environmental and local community outcomes, and are often constrained by scarce funding
and limited resources. Against this, the UK is in the middle of an infrastructure boom, with
HS2, Crossrail, Thames Tideway and Hinkley Point for example having a combined cost
potentially reaching £100 bn. In addition, thousands of miles of road and railway are built or
upgraded each year, hundreds of thousands of houses and millions of square meters of
commercial space constructed.
This contribution to the conference proposes that in addition to stand-alone river restoration
or catchment management projects, the application of innovative management techniques
on watercourses and catchments associated with infrastructure projects can, in aggregate,
unlock significant multifunctional benefits associated with traditional river restoration
schemes. By challenging the status-quo, actors in these projects can bring their influence to
bear on realising tangible and significant environmental enhancements, by looking beyond
mitigation and creatively identifying opportunities for the environment and society at
negative or low marginal cost for the scheme funder, most particularly when maintenance is
considered.
This presentation seeks to explore the balance of constraints and opportunities in this context
and provoke debate on how opportunities can be better realised. This will be undertaken
through an analysis of drivers for innovative and sustainable river and catchment
management as they currently exist across regulation, reputation and the influence of
stakeholders. Constraints and barriers to these approaches will also be examined and
consideration given as to how these might be overcome.
These points will be illustrated through the use of case study projects that the presenters
have personally worked on which draw on a range of experiences across sectors and client
types, and with varying degrees of influence.
Brief examination will also be given as to the range of future scenarios, and the new
challenges and opportunities presented through seismic shifts such as Brexit, in terms of
funding for infrastructure investment and regulatory context that may determine potential
for realising environmental benefits through infrastructure projects.
Session 2: Parallel Sessions Conference Theatre: Natural Flood Management in Practice
NFM: DELIVERING MULTIPLE BENEFITS THROUGH FLOOD RISK
MANAGEMENT
A. FRASER1 & S. REANEY2 1 Jacobs, 2 Durham University
The impact of flooding throughout the United Kingdom is significant and the financial burden
felt by individuals, communities and Government. Many flood alleviations schemes use hard
engineered approaches providing high standards of protection but do not address the root of
flood risk. The financial costs of these schemes cannot always be justified using the current
cost-benefit criteria. Furthermore, the delivery of these schemes can have significant negative
impacts upon river systems. Justifying the need to investigate sustainable, lower-cost
initiatives that can be delivered more holistically and sustainably. Natural Flood Risk
Management (NFM) is an area of great interest for this reason by supporting flood risk
reduction at a catchment scale as well as providing opportunity to deliver multiple benefits
to the catchment.
Durham University used two complementary approaches to appraising potential:
1. Rapid connectivity and risk mapping assessment (SCIMAP-Flood)
2. Detailed physically based, fully spatially distributed, simulation of catchment hydrology
(CRUM3)
Combining, these methods provides a powerful toolkit to target interventions within the
catchment and simulate potential impact on flood peak through a variety of NFM
interventions. Rapid risk mapping identifies the areas at greatest risk of generating overland
flow, a key factor in flood risk generation in rural catchments. The detailed simulation of
catchment hydrology provided by CRUM3 then provides a mechanism by which these
targeted interventions can impact upon flood peak reduction. Fraser (2017) found that
targeted interventions using SCIMAP-Flood yielded more efficient reductions in peak flow
compared to other targeting techniques. Additionally, as sediment transfer and diffuse
pollution are synonymous with overland flow by targeting interventions that intercept
overland flow or reduce its connectivity to the watercourse it is possible to achieve Water
Framework Directive benefits.
A variety of flood mitigation strategies were investigated; including land cover change, Large
Woody Debris (LWD) dams and spatially targeted attenuation. LWD offered the most efficient
peak flow reduction particularly when combined with spatially distributed attenuation.
REDUCING FLOOD RISK THROUGH GREEN INFRASTRUCTURE ON THE RIVER SOAR, LEICESTER
A. McDONALD1, H. O’BRIEN2 & R. NEEDHAM3 1 Environment Agency, 2 Leicester City Council, 3 Trent Rivers Trust
Leicester is a city of high flood risk whilst the River Soar and tributaries running through the
city suffer from diffuse pollution and physical modification. The Environment Agency &
Leicester City Council are working in partnership alongside the Soar Catchment Partnership
to solve this. Through tackling flood risk as a blocker to regeneration we’ve been able to
deliver schemes that improve the environmental, social and economic value of the river
corridor whist improving community ownership.
The Leicester conveyance scheme targeted underused public open space of low ecological
value. By reconnecting the river with its floodplain more opportunity for wetland species was
created. Solutions to flood risk were designed that incorporated pockets of natural habitats
to help to build more diverse and resilient ecological communities.
Improvements include a large wetland at Ellis Meadows linked to the River Soar. The area was
designed to have a permanent area of water to benefit aquatic invertebrates and amphibians.
The fringes of the wetland have been planted with species that can tolerate a range of water
levels, providing cover throughout the year. When water levels are low, mud will be exposed
providing foraging areas for waterfowl. Since its creation, grey heron and little egret have
been regularly seen along with an abundance of different types of dragonflies and bats are
regularly seen foraging over the wider habitat network. The connection with the River Soar
allows the area to function as a fish refuge helping to sustain fish populations in the main river
should a flood event occur. In total 1.5Ha of wetland habitat along the river corridor has been
created.
The new wetland area incorporates a series of boardwalks, providing interest and accessibility
to the new habitat created through the scheme. A series of information boards have been
included to raise awareness of environmental issues such as flooding and provide information
about the wildlife and plant species present. Usage of the public open space has increased
and the area is being used by schools as an outside classroom.
Scrapes within the floodplain improve the habitat interest. The scheme has also incorporated
a programme of Japanese Knotweed and Himalayan Balsam control in places along the river
corridor, aiding the establishment of more native marginal vegetation. In total around 100
trees and 7000 shrubs have been planted improving the foraging habitat available for the
local badger populations. 1 Ha of wild flower meadow has been created which will help to
support pollinators within the urban area. Bee posts and bat boxes provide additional
features and the mitigation badger sett is very well used.
This talk will cover how working in partnership, green infrastructure was put at the heart of a
flood scheme, the benefits seen to urban regeneration and the local community as well as
the ecology of the area.
PRIORITISING RESTORATION AND NFM IN THE RIVER PEFFERY, SCOTLAND E. J. T. LEWIN1 & H. REID2
1 Jacobs, 2 SEPA
SEPA’s Morphological Impact Assessment System (MImAS) tool, uses a series of spatial
datasets and impact ratings to determine the morphological status of a waterbody to assign
a Water Framework Direct (WFD) classification. MImAS has been used during the planning
stage of the Dingwall Flood Protection Scheme (FPS) commissioned by The Highland Council,
to develop a FPS for Dingwall and Blairninich, Scottish Highlands. The project aims to reduce
flood risk at Dingwall through both conventional and Natural Flood Management methods.
MImAS datasets were used with field observations to split the Peffery into a series of reaches.
Calculations were then applied to identify the reaches and pressures causing a reduction in
WFD status. The assessment was then used to give a score for a range of aspects, including
overall status of the waterbody, status of each reach and to highlight the impacts of different
pressures. These scores quickly identified the locations of specific pressures within the
catchment that are impacting on the morphological status of the Peffery. The outputs were
then used to prioritise the locations and types of restoration works, focusing on reaches
where improvements would make the greatest impact on morphological quality. High level
restoration options focusing on in-channel and floodplain NFM measures have then been
presented for each reach and modelled to quantify their impact on downstream flood risk.
The project aims to combine these restoration measures to reduce downstream flood risk
through further work.
MImAS has been successfully used to quickly highlight key areas in which to focus restoration
measures to improve morphological quality. MImAS and its associated datasets provide a
wealth of baseline information at a catchment scale for all WFD baseline waterbodies in
Scotland. They are useful not only for catchment scale restoration planning but a range of
geomorphological and ecological assessments. The tool robustly quantifies expert judgement,
allowing effective and rapid prioritisation of restoration measures at the catchment-scale.
While the MImAS output is extremely useful for indicating where to work in a catchment, it
should always be ‘sense-checked’ in the field to ensure that outputs are consistent with the
‘real-world’ morphological quality. Moreover, this allows restoration measures to be
designed to specifically tackle the geomorphic characteristics of degradation at a point. Could
a similar integrated dataset be collated for English and Welsh rivers as Fluvial Audits are
undertaken for projects? Could these be stored in an accessible online database and accessed
for other projects? This would allow us to rapidly assess 1) the distribution of river types and
their likely resilience to pressures, 2) the intensity of anthropogenic impacts at different
locations within catchments and 3) work out swiftly where we need to concentrate our efforts
and assess geomorphic condition and restoration options in more detail.
DO WE NEED AN NFM REALITY CHECK? E. GILLIES1, H. MOIR2 & L. CAMELO3
1 cbec eco-engineering UK Ltd and University of Glasgow, 2 cbec eco-engineering UK Ltd and University of the Highlands and Islands, 3 cbec eco-engineering UK Ltd
Many of the natural flood risk management tools we have at our disposal seem relatively
simple to apply: at a reach scale we often use the tools of embankment set back or
embankment removal, inset floodplains, and re-meandering, and large wood placements. In
some cases judicious use of these NFM tools works well at promoting reductions in flood risk
both adjacent to the intervention and downstream. Often it is a beneficial effect downstream
that is the main NFM design objective. However, an example where application of standard
NFM tools can have unforeseen, detrimental effects, is the case where existing embankments
are overtopped and greatly slow the return of water to the channel on its journey
downstream. In this situation, embankment set back can lower flood levels so embankments
are not overtopped, and/or embankment removal can speed up the return of floodwater back
to the channel resulting in an NFM design which increases the downstream hydrograph peak
compared to that for existing conditions. Often this effect is more apparent for extreme high
flows (like the 1:100/y and 1:200/year design events) compared to lower flood return
intervals. We use unsteady hydraulic modelling of several NFM scenarios where
embankments are moved, set-back or removed to demonstrate cases where NFM works, and
where NFM tools could be detrimental. However, we also show how the hydraulic modelling
can be used to tune and adjust a basic NFM design to achieve the desired natural lowering of
flood risk. We also describe minimum technical standards for modelling NFM scenarios at the
reach scale.
Conference Suite 2: Evidencing Change
EVALUATING RIVER RESTORATION TECHNIQUES: SETTLEMENT PONDS IN THE AFON EDEN CATCHMENT, NORTH WALES
H. MARPLES1 & S. HEARN2 1 Bangor University, 2 Natural Resources Wales
Freshwater pearl mussel populations are declining across Europe due to habitat degradation
and overfishing and are now classified at a European level as critically endangered on the
IUCN red list. The Pearls in Peril (PiP) LIFE funded project, which was completed in 2016, aimed
to improve habitat quality for the species in Special Areas of Conservation (SACs) across the
UK. The Afon Eden - Cors Goch Trawsfynydd SAC in North Wales, designated for pearl mussels,
was part of the PiP project and several catchment and in-stream restoration interventions
were carried out. Settlement ponds were created in a former conifer plantation (Brynteg
Forest) which had been identified as a source of suspended solids, nitrate and phosphate to
the Afon Eden. The intention was that the ponds would trap suspended solids and prevent
them from entering the Afon Eden SAC. This study re-visited ten of the ponds in 2017 (two
years’ post construction) and carried out water quality monitoring of the inflows and outflows
as well as measuring accrued sediment. It also analysed whether various water quality
parameters complied with the thresholds required for the survival of freshwater pearl
mussels.
In general, water in the outflows was found to have lower concentrations of suspended solids,
nitrates, phosphates and conductivity than water in the inflows, along with higher levels of
dissolved oxygen and water temperature. Concentrations of suspended solids were lower in
the outflow than the inflow of seven of the ten ponds, suggesting that they are retaining
sediment. In the three remaining ponds, the concentrations of suspended solids increase
from the inflow to the outflow, suggesting that they are already full and have no spare
capacity to retain further suspended solids. Despite this study not finding an overall significant
reduction in suspended solids, the accrued sediment shows that the ponds are effective at
trapping sediment. Pond size plays a key role in the rate of removal, with larger ponds
removing a greater percentage.
Suspended solids, nitrates, phosphates, dissolved oxygen and conductivity measured in the
outflows all met the current requirements for the survival of freshwater pearl mussels. The
pH was found to be too acidic, however this may have a limited effect on the mussel
population due to dilution downstream. Further study is recommended into: catchment
hydrology and pond functioning, impact of recent rain events on water quality, effect of pond
design on performance and alternative techniques for measurement of accrued sediment.
Suggestions are made for the design and location of constructed wetlands and measurement
of improvements on habitat quality for pearl mussels.
THE ROTTAL BURN RESTORATION PROJECT: COLLABORATIVE EVIDENCE AND IMPACT FROM RIVER CHAMPIONS, RESEARCH COLLABORATORS (AND LOTS
OF STUDENT PROJECTS) R. WADE1, K. A. DEMPSEY2, C. MacINTYRE3, A. BRAID4 & A. TOMCZYK5
1 Abertay University, 2 River South Esk Catchment Partnership, 3 Esk Rivers and Fisheries Trust, 4 Millard Consulting, 5 Jacobs
This presentation provides morphological, ecological, community and wider evidence of
change and impact from a restored river system monitored over 5 years. The Rottal Burn in
Angus, Scotland was remeandered in 2012. In the intervening years stakeholders and
researchers have worked together and have pieced together multiple student projects to
provide a broad and contextualised evidence base for the benefits. The evidence base
presented in this talk will track the morphological change, river habitat and ecosystem service
development, recorded as the system has matured and will also showcase stakeholder
perceptions and community and catchment outcomes. Whilst the multiple benefits of
working together are highlighted, the evidence gaps and research needs are also discussed in
this jointly delivered presentation.
IMPLEMENTING FLOOD RISK MANAGEMENT AND RIVER RESTORATION TO CONSERVE INSTREAM HABITAT FOR BROWN TROUT
N. V. ANGELOPOULOS1, J. P. HARVEY1, J. D. BOLLAND1, M. A. SMITH1, M. J. TAYLOR1, A. D. NUNN1, R. A. A. NOBLE1, I. G. COWX1, J. E. G. MASTERS2 & J. MOXON2
1 Hull International Fisheries Institute, School of Environmental Sciences, University of Hull, 2 Environment Agency, Fisheries, Biodiversity and Geomorphology
Flood Risk Management (FRM) is imperative to reduce the risk of flooding to properties and
infrastructure but can profoundly affect the physical habitat of a river and key biota, such as
fish. FRM can involve the removal of key riverine habitat characteristics, for example,
meanders and instream features such as trees, riparian vegetation, shallow gravel areas and
islands to create a wider, often deeper and less complex channel to support the conveyance
of large volumes of water. This process subsequently degrades the principle functional habitat
units in rivers required for fish spawning, recruitment, feeding and refuge and therefore, can
have undesirable effects on the survival of a particular life stage of fish, resulting in
displacement, gradual or sudden declines in populations or mortality.
FRM is dependent on political support through legislation, such as the European Floods
Directive (2007/60/EC) and in the UK, the Flood and Water Management Act ((FWMA) 2010),
developed in response to the Pitt Review (2008) commissioned following the 2007 floods.
Historically, FRM in Europe was used to merely support economic and social benefits, but
now, where possible, the process endeavours to incorporate ecological integrity under the
European Water Framework Directive (EU WFD) and Habitats Directive. This synergistic
approach between cross-sectoral river ecosystem services such as FRM and river restoration
aims to support and maximise multiple benefits between sectors. FRM activities are predicted
to intensify in the future because of an increase in extreme flow events, yet few studies
provide ecological monitoring and evaluation for the integration of FRM and river restoration,
limiting our understanding of how rivers and fish populations respond to instream works. The
lack of studies are often due to restricted timescales and limited funding for monitoring and
evaluation but post implementation evaluation is critical to inform river mangers, policy
makers, project partnerships and stakeholder groups in the planning and development of
future FRM and river restoration projects.
In June 2007, following a 1-in-150 year flood event in Sheffield, South Yorkshire, England,
4,000 homes and 1,800 businesses were flooded (Pitt Review 2008). In England, the
Environment Agency is responsible for delivering sustainable FRM and in 2009 they undertook
FRM works at Malin Bridge, Sheffield to reduce the risk of flooding. Subsequent river
restoration aimed to rehabilitate the physical habitat and conserve the local brown trout
(Salmo trutta L.) populations. In this paper we present the findings of long term (8 years)
habitat and brown trout investigations at Malin Bridge, and includes, pre-FRM works (2009),
post-FRM works (2010), post-restoration works (2011) and subsequent annual investigations
(2011-2016). Specific objectives were to compare juvenile, sub-adult and adult brown trout
(i) habitat quality and availability (ii) population density and (iii) utilisation of habitat, before,
during and after FRM and river restoration works.
ENGAGING WITH RIVERS IN FOUR DIMENSIONS L. SHUKER1, A. M. GURNELL2, G. WHARTON2, J. ENGLAND3 & D. J. GURNELL4
1 Thames 21/Cartographer Studios Ltd, 2 Queen Mary, University of London, 3 Environment Agency, 4 Cartographer Studies Ltd
Many excellent biological and water quality monitoring initiatives are evolving across
catchment partnerships, with several including the potential to engage enthusiastic citizen
scientists. However, existing methods provide sparse information about physical processes,
structure and habitat of rivers.
The Modular River Survey provides a versatile framework for river managers and volunteers
to investigate and monitor physical aspects of river environments. The survey combines data
at three scales: short river reaches (MoRPh survey: 10-40m length) to link with biological data;
intermediate reaches (MultiMoRPh survey: 100-400m length) to synthesise the river’s
physical habitat structure and functioning; and long reaches (HydroMoRPh analysis: 10+km)
to précis the river type (slope, width, sinuosity, number of active channels), modifications
(land use, infrastructure) and rate of adjustment (widening, narrowing, migrating) over
decades. The three scales of survey are nested to reveal the changing physical character of a
river in space, and the fourth dimension: time.
This presentation will explain the rationale behind the MoRPh (Modular River Physical),
MultiMorph and HydroMoRPh surveys and analysis, and will elaborate on their
complementary roles in describing and assessing river physical characteristics at over a range
of space and time scales.
We report on the first year of application of MoRPh and MultiMoRPh in terms of the quantity
and geographical distribution of the data that have been collected and overarching trends;
providing also an update on future directions in development of the Modular River Survey
framework.
Conference Suite 3: Barriers
NOVEL DESIGN, INSTALLATION AND ASSESSMENT OF COARSE FISH PASSAGE USING LOW COST BAFFLE (LCB) SOLUTION AT A GAUGING STATION T. HULL1, A. LOTHIAN2, C. GARDNER1, J. TUMMERS2, D. GRIFFITHS3, M. LUCAS2
1 South East Rivers Trust, 2 Durham University, 3 Environment Agency
Kingston gauging weir on the Hogsmill River, a tributary of the Lower Thames, is the most
downstream obstruction in the catchment and presented a complete barrier to fish passage.
The gauging weir was atypical, having a downstream face slope of 1:3.3 (30%) instead of the
1:5 (20%) slope that the standard Low Cost Baffle (LCB) arrangement was designed for. The
use of a standard LCB solution on this steep gradient is unproven and unlikely to be effective
due to hydraulic considerations. Standard LCB on a 24% sloped weir have previously been
shown to be effective in facilitating upstream passage of brown trout Salmo trutta. However,
there is no peer-reviewed literature on the use of LCB in aiding upstream passage of coarse
fish, although one grey literature report does provide some evidence of successful passage of
coarse fish. Furthermore, there is no literature regarding the use of LCB in facilitating fish
passage at a weir with such a steep slope as the Kingston gauging weir.
A collaborative project between the South East Rivers Trust and Environment Agency aimed
to achieve multi-species passage whilst maintaining gauging accuracy. A novel design of LCB
was developed which theoretically would provide suitable conditions for the passage of
coarse fish. Further investigations were undertaken to inform the position of the upper baffle
so not to compromise gauging accuracy.
Passage efficiency of dace, chub, roach and barbel from wild (n=274) and farmed sources
(n=239) was studied by Durham University using Passive Integrated Transponder (PIT)
telemetry. The study covered five months through the peak migratory season to measure
passage performance. This information will i) inform locally on fish passage at the site, ii) give
insight for the suitability of LCB at similar weirs elsewhere and, iii) contribute to a PhD
academic study.
The study has demonstrated 45% and 35% passage efficiency over the baffles and whole
structure respectively, for a range of coarse fish species of different sizes. The study explored
the effects of various parameters on passage including flow discharge, temperature, diurnal
patterns and fish size. Now that the novel LCB design has been demonstrated to be effective,
the principle can be disseminated and implemented on other weirs with similar gradients,
which have previously been considered unsuitable for the LCB solution.
THE IMPACT OF WEIR REMOVAL ON THE FORAGING AND ACTIVITY OF BRITISH BATS
S. SCOTT1, C. TURTLE1 & J. COLLINS2 1 Environment Agency, 2 Bat Conservation Trust
Bats are useful bio-indicators of environmental health and are used by Defra as indicators of
environmental change. Some bats are affected by the habitat quality and water quality of
British rivers. This project considers the impact of in-channel habitat changes following weir
removal on the foraging and activity of British bats, and the need to address this in river
restoration schemes.
The Water Framework Directive (2000/60/EC) sets strict criteria for rivers to meet Good
Ecological Status. This is assessed as a measure of a river’s hydromorphological, chemical and
biological state. Fish, aquatic invertebrates and macrophytes are used as biological indicators.
For a river to meet ‘Good Ecological Status’ all quality parameters need to be met. In-channel
structures are often a reason for ecological failure. Weirs have previously been introduced to
river systems for milling, hydropower and aesthetic reasons. However, they are a barrier for
fish passage and affect in-channel morphology. In-channel structures which prevent fish
passage are often removed to deliver the Water Framework Directive actions.
Sections of smooth water are found behind weirs; the length of still water depends on the
head of the impoundment and the gradient of the river channel. When a weir is removed the
river will revert to ‘natural’ geomorphic processes. Dependent on the flow regime and
sediment load within the channel, pool/riffle systems will be formed. The creation of ‘natural’
conditions has multiple benefits for wildlife, particularly those species which require areas of
faster flow and gravels in their life-cycle.
However, removing areas of smooth water can potentially have a negative effect on some
species. For example, bats use a sophisticated system of echolocation for navigation that can
be disrupted by irregular/highly mobile objects. Sound echoes produced from echolocation
calls scatter when in contact with irregular surfaces and make foraging and navigation
difficult. On rivers, bats have been known to avoid using riffle habitats for this reason. Some
bats, are also adapted to forage over smooth water. For example, Daubenton’s bats feed by
trawling for insects over water using specially adapted feet to clasp aquatic invertebrates
close to the water’s edge.
The impact of weir removal on bat activity is not widely considered when carrying out river
restoration schemes. Removing large areas of important foraging habitat could affect the
conservation status of British bats, particularly the Daubenton’s bat. The Environment Agency
and Bat Conservation Trust are working in partnership to investigate this issue. The outcome
will be an evidence directory of case studies, monitoring methodology and guidance on
mitigation techniques.
NEW GUIDE TO FISH PASSAGE AND SCREENING AT FLOOD RISK MANAGEMENT AND LAND DRAINAGE STRUCTURES BASED ON PRACTICAL
EXPERIENCE O. SHOLI1, R. PILCHER1, T. HARDING2, J. BOLLAND3, A. DEACON1 & R. HORSFIELD2
1 AECOM, 2 THA Aquatic Ltd, 3 Hull Institute of Fisheries
We are developing a new guide and supporting tools which synthesise existing research,
guidance and practical experience to help the planning/appraisal, design, construction and
maintenance of fish and eel screens, deterrents, passes and fish-passible pumps at structures
such as pumping stations, weirs, locks, sluices and tidal outfalls.
Production of the new guide is being directed by a Project Advisory Panel comprising end-
user representatives from organisations such as the Environment Agency, Natural Resource
Wales, Internal Drainage Boards, Lead Local Authorities and Natural England.
The new guide will also be relevant to anyone interested in passage and deterrent measures,
especially as it is intended to help link fisheries science with practical implementation. The
primary audience of the new guide will be the flood risk management authorities (RMAs) and
we anticipate it being particularly useful to Internal Drainage Boards.
The project and fish passage measures described have strong links to River Restoration. Many
of the solutions outlined, such as weir removal, are classically considered to be river
restoration techniques. Through the provision of fish and eel passage measures at sites, each
of the solutions outlined in the guide provide a naturalisation of the system in accordance
with the tenants of river restoration.
The project has strong links to both existing fisheries scientific knowledge and current
research studies, with the guide and decision support tool being built in order to facilitate the
appropriate design and delivery of the passage solutions (whether at new builds or when
retrofitting solutions).
Central to the aims of the project are to encourage partnership working through gaining
knowledge on design solutions from scientists and suppliers as well as meeting with
practitioners on site and those that have built solutions. Lessons learned have been gleaned
through interviews with experts and from our extensive programme of sites visits, which are
discussed further below.
The guide and decision support tool are to be designed so that they can be adaptive. They are
to be based on fish behaviour and in channel infrastructure, taking into account current
legislation and funding mechanisms, noting that the latter two will likely change in the years
ahead (for example once the full impacts of Brexit have come to fruition).
The project team have recently completed a literature review and programme of
approximately 40 site visits throughout the United Kingdom at a range of in channel
structures, varying in nature and scale. This has been complimented by an extended visit to
the Netherlands where the project team visited a further 10 sites and witnessed first-hand
some of the innovations the Dutch have applied to help improve fish and eel passage at
structures.
Work on producing the new guide started in November 2016 and is due to be completed and
disseminated by the middle of 2018.
APPROACHING 10 YEARS ON - SHEDDING LIGHT ON STREAM DAYLIGHTING AROUND THE WORLD
A. T. BROADHEAD1 & T. C. WILD2 1 Arup, 2 University of Sheffield
Deculverting, or 'daylighting', involves opening up buried watercourses and restoring them to
more natural conditions. It is often claimed to provide multiple benefits to society, the
environment and the economy, and spans multiple disciplines in river restoration, flood risk
management, urban design and ecology. As a form of river restoration, it has arguably gone
mainstream in the last decade, with numerous projects from understated to prize-winning,
large and small, urban and rural, across the UK and internationally in recent years. Daylighting,
and specifically “lost rivers”, are subjects that continue to inspire the public and popular
media. However, the outcomes and objectives of deculverting projects are rarely published,
which makes it difficult to evaluate their true effectiveness, determine the best methods to
use, or provide quantitative evidence to encourage future projects. To address this challenge,
www.daylighting.org.uk was established as a map-based website where practitioners and
researchers working on deculverting projects are encouraged to enter case study information,
as well as browse past case studies for inspiration or information and contact details. This talk
will assess the current state of stream daylighting in 2018, drawing on nearly 10 years of
collecting hundreds of case studies from around the world via www.daylighting.org.uk. We
hoped that disseminating the results of deculverting projects would help to deliver improved
practices and policies to promote deculverting. We examine changes in policy and practice,
look at the best examples and lessons learnt, and attempt to shed light on the future of
daylighting our lost urban rivers.
Session 3: Parallel Sessions Conference Theatre: Working in Partnership
BETTER TOGETHER - HOW WORKING IN PARTNERSHIPS HAS ACHIEVED SO MUCH MORE IN TELFORD'S URBAN CATCHMENT
G. PLUCKWELL1 1 Environment Agency
The Love Your River Telford project is a holistic, all inclusive, partnership approach, aimed at
improving water quality, biodiversity and flood resilience within the town of Telford by
complimenting physical improvements with community engagement. By bringing together
organisations with similar aspirations and working with volunteers, schools, businesses and
the local community, significant benefits have been achieved. This efficient and proactive
partnership approach has resulted in both non-financial and financial gains.
The hub of the whole idea we’ve called the Clean Stream Team (CST). The CST has 4 members:
the EA, Water Company and the Local Authority. They are supported by the town’s
community and the other project partners. The CST’s objectives are to proactively seek and
resolve as many water environment issues in the town for the life of the project by sharing
local knowledge, equipment, expertise and powers. The community recognises visual signs of
water pollution and how to alert the CST to the problems.
Shropshire Wildlife Trust are the main delivery partner and oversee most of the work on the
ground. Our community awareness initiative has engaged with over 1000 school children
through the River Ranger Education Programme, over 200 businesses through the Blue
Business Awards, over 10 different volunteer groups through training and providing them
with monitoring equipment, as well as local residents through the media and awareness
leaflets. All of our engagement highlights how to identify the signs of pollution in the water
environment and how to alert the CST.
Community engagement directly compliments the physical improvements we’ve made to the
town’s watercourses. Physical improvements have taken many forms and include: 300m of
deculverted watercourse, >1km of bankside habitat improved, 3 “Depave” raingardens
implemented, a highways SUDS deployed, >4000m2 of flood storage created, woody debris
structures along >400m of watercourse, >2000m2 of wetland regenerated and a
bioremediation island installed.
The project is in its 4th year. The community engagement continues as described above and
will compliment further physical improvements planned.
Environment Agency monitoring data, combined with the projects intensive monitoring
programme and volunteer collected data helps the project locate issues, target resources,
identify mitigation measures and detect improvements.
Watercourses in the town have already shown improvements with a jump up in at least 1
WFD status in 5 of the 8 present. Habitats have been created and enhanced, localised flood
risk reduced and efficiencies resulting in a potential saving in excess of £3M for project
partners realised.
The urban catchment management model created in partnership in Telford compliments
community engagement with physical improvements works. It has gained recognition both in
the UK and overseas, resulting in a number of towns either implementing the model or
seeking funding to do so.
TOWARDS A WILDER RIVER CRANE: BENEFITS OF PARTNERSHIP DELIVERY T. WHITE1 & P. SOVIC DAVIES1
1 London Wildlife Trust
London Wildlife Trust staff worked with Ealing, Hillingdon, Hounslow & Richmond-upon-
Thames councils to develop & deliver river improvement plans for over 5km of river, covering
10 public green spaces throughout the River Crane catchment in west London.
The design of habitat interventions was driven by several key requirements such as delivery
by local volunteers, use of local recycled materials, funding restrictions & a desire to improve
site appeal (including security) & public access, in addition to the challenges posed by the
urban nature of the River Crane. A volunteer training programme, covering the conservation
rationale, practical restoration work & health & safety aspects, was key to the project’s
success & good volunteer retention, enabling over 30 key volunteers to confidently deliver
work over a six-month period. Training was delivered over four sessions in different locations,
providing local volunteer opportunities. Following completion of the project, a large
proportion of volunteers joined other Trust activities in the Crane Valley.
A series of habitat improvements were delivered at Brookside Open Space, Crane Park Island,
Yeading Brook Meadows & Gutteridge Wood Nature Reserve between autumn 2016 & winter
2017. Following tree work delivered by local authorities & a specialist contractor, volunteers
recycled cut branches to create brash berms within the river channel to soften reinforced
river banks, create variation in flow, & encourage development of in-channel vegetation. In
addition to this, flow deflectors & hinged trees were installed in appropriate locations, while
unnecessary bank reinforcements were removed. These interventions significantly improved
the river’s habitat for fish, invertebrates & other wildlife, in line with local BAP objectives.
At all sites access was improved by opening up a riverside trail & clearing accumulated litter.
The newly cleared areas of river bank with footpaths reduced anti-social behaviour, improved
perception of safety & encouraged local residents to access the sites & appreciate the river,
which was reflected in documented positive feedback. Through the project the Trust worked
with more than 200 volunteers, ensuring that local people develop a duty of care for the river,
whilst reinstating the Crane corridor as an important green asset. In addition, they assisted in
contributing towards the London BAP targets for river restoration.
The project demonstrated that several components were key to strategic delivery of habitat
improvements across several local authorities, particularly liaison with stakeholders through
the catchment partnership & a close working relationship with the local authorities, through
all stages of the project. This approach built a clear understanding of responsibilities of all
involved partners, which, together with an intense public engagement volunteer training
programme, will be the main driver to secure long-term maintenance of the improved sites.
LIVING HERITAGE OF THE RIVER DON
R. WALKER1 1 Don Catchment Rivers Trust
The ambition of Don Catchment Rivers Trust (DCRT) is to reconnect people, communities and
decision makers back to the River Don and its rich natural, cultural, built and industrial
heritage. We want to change their beliefs and attitudes so that the River Don and its heritage
will be better valued as a major asset to South Yorkshire and better protected into the future.
Whilst identifying funding for a fish passage scheme in Sheffield on five un-owned weirs the
Trust took the opportunity to progress this ambition by applying for major funding with the
Heritage Lottery Fund. There was an emphasis on engaging partners and communities and
the project has three main aims: To inspire and mobilise the community; to develop skills for
heritage and capacity; to foster understanding and change perceptions.
Working under these three aims, the Trust set about creating a programme of engagement,
employing a Community Engagement Officer and project staff. To ‘inspire and mobilise the
community’ the Trust opened itself to recruiting and training volunteers to carryout
conservation work. DCRT now has a dedicated group of volunteers as well as corporate
volunteers. We tackle ‘hot spot’ areas along the river, improving access and removing decades
of litter and overgrown vegetation to make the river a better place to be for people and an
asset to their local communities. We have also created our ‘River Guardian’ school sessions,
which aim to bring classes out to visit the river and learn about their local environment – why
learn about the River Nile when the River Don is on your doorstep!
A key aim of the project is to upskill people so that they feel confident in volunteering, so to
‘develop skills for heritage and capacity’ we run a programme of formal and informal training
days for volunteers on subjects ranging from identification skills to first aid courses. We also
now employ an apprentice, who is working towards a Level 2 qualification in Environmental
Conservation.
Perhaps the most important aim is to foster understanding and change people’s perceptions
of the river. 40 years ago the River Don was ‘dead’ owing to decades of industrial activity. This
is an image that sticks in people’s minds, so we run community discovery events and walks
and make sure we get out and about to events. The Trust has set up the Don Valley Way
walking trail to encourage people to visit and look after the river.
Don Catchment Rivers Trust does not own or have responsibility for any part of the river, so
of course for Living Heritage of the River Don to be successful we had to develop our
partnerships. We work closely with statutory bodies, organisations, charities, as well as
community groups, and partnership working permeates everything we do. From getting
permissions for works, to tapping into local authority marketing outlets, to getting piles of
rubbish collected by the Council - partnerships have become an important part of Don
Catchment Rivers Trust.
‘SMARTER WATER CATCHMENTS’ IN THE EVENLODE – WORKING IN PARTNERSHIP TO REDUCE PHOSPHORUS IN RIVERS
Y. de GARIS1, J. WESTLAKE1, M. HUBAND2 & S. OLNEY3 1 Thames Water, 2 Atkins, 3 Natural England
Excessive levels of phosphorus can damage the river environment, for instance by generating
algal blooms. In rural areas, run-off from agricultural land and discharge from sewage
treatment works can both be significant sources of phosphorus in natural waters. Thames
Water is committed to continued investment in treatment processes that improve the quality
of effluent discharged to river from its works. However, the company is also exploring
whether it can make a cost-effective contribution to managing phosphorus in natural waters
by supporting farmers in the implementation of catchment measures.
We set up a trial in three headwater catchments of the River Evenlode to explore how a water
company can work with local farmers and environmental partners to reduce the loss of
phosphorus to rivers. The trial set out to achieve the following:
Explore the logistics and practical challenges of a water company working with farmers
and other partners to deliver effective catchment management.
Understand the value of catchment management to customers. Is it a cost-effective use
of their money? Do measures to reduce phosphorus generate additional environmental
benefits that they also value?
Assess the effectiveness of measures at reducing phosphorus loss in a lowland Thames
catchment.
The project has now been running for just over two years, with a catchment management
scheme and associated measures launched in September 2017
(www.thameswater.co.uk/evenlodecatchment). This paper discusses the successes and
challenges experienced in the project so far, drawing out the some of the novel aspects of the
study by broadly focussing on the following themes:
Engagement: We have focussed on forging strong relationships with farmers as well as
partner organisations such as the Evenlode Catchment Partnership. This is an ongoing
process. Good advice depends on understanding the way a farm operates; farmers are
more likely to participate in a scheme if they know and trust the person providing advice.
Likewise, collaborative schemes with local environmental partners with the potential to
yield multiple benefits require close working relationships to plan, design and implement.
Developing an evidence base: a strong evidence base on the implementation costs and
effectiveness of measures to reduce phosphorus is needed a) to direct investment during
the trial and b) to assess the value catchment management delivers to customers.
Evidence on the wider environmental and social benefits of measures is also essential in
establishing the full ecosystem services provided by the scheme.
Flexibility The scheme has been designed to be broad enough to evolve flexibly in
accordance with the requirements of local farmers, and to take advantage of
opportunities to work with local partners. Farmers are encouraged to propose innovative
measures of their own.
Conference Suite 2: Managing Sediment and Pollutants
CONTAMINATED SEDIMENT: ASSESSING RISKS IN UK RIVERS I. DENNIS1, C. RODGERS1, P. WILLIAMSON1 & J. KWAN2
1 Royal HaskoningDHV, 2 CIRIA
Sediments in rivers often contain substances from both naturally occurring and
anthropogenic sources at concentrations that can potentially harm the health of the aquatic
environment and present a risk to human beings. These contaminants can be moved with
natural river sediment and stored in river channels and floodplains. They can also be disturbed
by natural flood flows, river maintenance and dredging, or development activities. The
contamination can affect the ecology of the water body and human health, through bathing
or fish consumption. The management of sediments has an important role to play as the UK
works to meet its Water Framework Directive (WFD) objectives to improve water quality and
achieve 'good status' in surface water bodies.
Royal HaskoningDHV is currently producing a guide for risk assessment and management of
contaminated sediment for the Construction Industry Research and Information Association
(CIRIA), to be published in Spring 2018. The aim of this national guidance is to provide practical
information on how to understand, assess and manage contaminated sediment in natural and
man-made water environments. This guide is targeted at a wide range of stakeholders who
have an interest in the management of contaminated sediment or who may encounter
contaminated sediment while undertaking works in the aquatic environment. It is designed
to provide the reader with a summary of the information they need to determine whether
contaminated sediment is present, characterise the extent and nature of contamination,
assess the risks that the contamination poses, and, where appropriate, provide guidance on
proactively and effectively managing these risks.
The CIRIA guide draws on the extensive literature available on this topic and Royal
HaskiningDHV’s practical experience in this field. It builds on Royal HaskoningDHV’s findings
from our recent research for the Department for Environment, Food and Rural Affairs (Defra)
into the risks posed by contaminated sediments across the country as part of the
organisation’s Non-Agricultural Diffuse Pollution Strategy. The project used an extensive
desk-based review of literature to produce a detailed conceptual model for potential
contaminated sediment risks in the freshwater and marine environments. A comprehensive
database of contaminated sediment quality was then compiled from available data sets and
combined with information on potential sources of contamination, receptor sensitivity and
physical characteristics to inform a GIS-based national risk assessment. This allowed the
likelihood and consequence of contamination to be determined, and the scale of risk to be
assessed.
Our presentation will discuss the key messages from this latest guidance for anyone working
in water environments where contaminated sediments are likely to be a risk, and will explain
how the CIRIA guide can be used to assess and manage this risk to support a healthy river
environment.
MANAGING ACCUMULATED SEDIMENTS: BENEFICIAL USE OF DREDGED MATERIAL (BUDM) AND WORKING WITH NATURE (WwN)
W. COULET1 & W. MANNING1 1 Exo-Environmental
Accumulated sediments within riverine and coastal systems pose a potential risk to
ecosystem health and functioning, flood management and navigation. Dredging is one tool
that can be employed in the management of accumulated sediments, helping to ensure good
water quality and habitat health, supporting the management and alleviation of flood risk and
providing sufficient water depth critical for navigation and the safe movement of waterborne
traffic.
Dredged material however is defined as a waste under the EU Waste Framework Directive
(WsFD). Consequently, the handling, transportation and disposal of dredged material is costly,
logistically challenging and presents additional challenges to the management of
accumulated sediments. This often results in significant economic constraints and hinders the
long-term management of historic coastal and inland navigational waterways.
The WsFD waste management hierarchy promotes “preparing for re-use” as a preferred
sediment management strategy for all arising material and can be achieved through various
applications of “Beneficial Use of Dredged Material (BUDM)”. This practice considers dredged
material to be a resource rather than a waste and when applied appropriately, BUDM can
offer significant economic, social and environmental benefits over historic sediment
management techniques, such as disposal offshore or in landfill. Similarly, employing the
“Working with Nature” philosophy during the design of BUDM projects, allows win-win
solutions to be identified and realised simultaneously for both infrastructure developments
and the natural environment.
The presentation by Exo Environmental Ltd “Managing Accumulated Sediments: Beneficial Use of Dredged Material (BUDM) and Working with Nature (WwN)”, aims to provide an introductory overview of available options for BUDM, following best practice according to current guidelines from specialist bodies such as the Central Dredging Association (CEDA) and International Navigation Association (PIANC) with illustrated case studies having relevance to flood defence, habitat restoration and agricultural improvements. Potential techniques that will be highlighted include:
- The use of geotextile tubes for sediment containment and habitat creation, - Restoration of intertidal habitats in an estuarine system, to enhance biodiversity and
support local sea defences, - The valorisation of a waste material through the development of products for
applications in coastal defence, and - Agricultural spreading for soil enhancement.
SILT MANAGEMENT CAN BE EASY...WHY ARE SO MANY PEOPLE GETTING IT WRONG? R. HAINE1
1 frog environmental
This presentation will draw from the practical experience of frog environmental and our
associate practitioners over the past 12 months from visiting construction projects that have
had varying degrees of impact on nearby rivers.
A review of the main underlying reasons for failures that lead to silt pollution events will be
discussed. These range from organisational issues such as poor communication through to
more practical issues such as a lack of site investigation and monitoring.
Climate change, a dynamic evidence base and a firmer line taken by regulators regarding silt
pollution all lead us towards a rethink on how we should be managing the risk of silt pollution.
This talk will also use practical examples of good practice to demystify some of the challenges
of controlling silt and put forward the argument that with good planning the majority of
projects can protect local watercourses by using low cost, passive methods that are readily
scalable.
PARTNERSHIP WORKING IN THE SUSSEX OUSE CATCHMENT S. LOHREY1, R. KELLY2 & E. LONG3
1 South East Water, 2 Natural England, Catchment Sensitive Farming, 3 National Trust
Drinking water resources in the River Ouse catchment in Sussex are being compromised by
increasing levels of pesticides and turbidity. In 2015 South East Water began catchment
management work in the River Ouse by undertaking investigation work alongside the delivery
of pilot trials to test the effectiveness of catchment measures. The aim of the catchment
investigation work was to identify the possible sources of pesticides and turbidity and their
pathways to water, and to identify solutions. These investigations included water quality
monitoring, desktop studies, catchment walkover surveys and modelling work. Catchment
Management has been delivered in partnership with Natural England’s Catchment Sensitive
Farming officers, working with farmers and land managers to address the sources of diffuse
pollution.
Part of the catchment investigation work and options appraisal has focused on Working with
Natural Processes and how these options can deliver multiple environmental and social
benefits. In 2015 South East Water identified an opportunity to work with the National Trust
on a river restoration project at their Sheffield Park estate in East Sussex.
The River Ouse has been heavily modified over the years and certain stretches have been
deepened and straightened to allow for navigation. The National Trust’s aspiration for the
Sheffield Park project was to reconnect the River Ouse back to its original 8 hectares of flood
meadows and to reinstate historic meanders. The National Trust’s objectives were twofold;
to restore and enhance the ecological function of the site and reconnect people to nature,
improving visitor experience at Sheffield Park. The catchment investigation work identified
an opportunity to use the floodplain to temporarily store river water during high flows, thus
encouraging the deposition of sediments and nutrients and the biological breakdown of
pesticides. This approach builds upon similar smaller scale techniques used to tackle diffuse
pollution in agriculture such as constructed wetlands and swales.
South East Water worked with the National Trust, the River Restoration Centre and CBEC to
design a scheme which met both parties’ aspirations. The final design incorporates bank
regrading, in-channel hydraulic controls and floodplain scrapes to encourage sediment
deposition. This design has meant that the meanders have been partially reinstated but the
main river channel has been left open. Works were largely completed during autumn 2017,
with further work planned for spring 2018. Monitoring will include the installation of turbidity
sensors in the river channel at upstream and downstream locations and also trialling
‘sediment mats’ that are to be positioned on the floodplain. The National Trust will also
monitor the biodiversity of the site and visitor numbers.
South East Water will use the evidence gathered from the Sheffield Park project to evaluate
river restoration as a measure to deliver water quality improvements.
Conference Suite 3: Novel ways of using Data
HISTORICAL STUDIES FOR INFORMING SUSTAINABLE RIVER RESTORATION STRATEGIES
J. COX1 1 Ricardo/University of Portsmouth
Understanding the history of rivers is important for shaping their future. The accessibility to
resources that may support historical studies has improved over the last two decades. This
project aimed to explore these resources to inform river restoration strategies of the River
Rother, West Sussex. The river drains 350 square kilometres of the South Down National Park
and has been a critical water resource for the local population for over a millennium.
Concerns for the river’s ecological health have been raised due to poor fisheries and in-
channel fine sediment deposits. Fine sediment accumulation near a drinking water
abstraction point also has the potential to disrupt the operations of a local water company.
These issues have largely been attributed to increased fine sediment inputs from agricultural
sources since the 1970s. This project challenges previous research with new evidence that
suggests in-channel sediment transport processes may be responsible for a significant
amount of the fine sediment issues observed in the lower catchment.
A range of methods were used to examine how the river has changed over time and assess
which areas of the river may naturally scour, transfer or accumulate sediment. Methods
include a review of archival evidence, a reconnaissance field survey and the application of
broad-scale sediment budgeting tools. Archival sources suggest that problems associated
with fine sediment accumulation resulting in poor fisheries are not new. Historic channel
modifications, including the construction of mills and the cutting of the Rother Navigation,
have significantly altered sediment transport processes. In-channel structures have been a
major control of deposition and erosion within the catchment such that the channel itself may
be a main source of sediment.
It is possible that more recent agricultural practices on the immediate floodplain and the
introduction of invasive species of flora have exacerbated rates of bank erosion. Indeed,
evidence suggests that bank erosion rates have increased since the mid-1970s. The acts of
widening, straightening and increasing river bank heights have probably promoted in-channel
sediment accumulation and reduced the potential for floodplain sediment storage. Evidence
suggests these floodplains have been actively managed for over a millennium, with flooding
and deposition of fine sediment promoted to improve agricultural productivity. The inherent
low slope and overwide channel geometry within the lower catchment indicates that the
lower reaches of the river are highly likely to aggrade, even if sediment inputs from the
catchment are reduced. Thus, the restoration of longitudinal and lateral sediment
connectivity within the system may be critical. The findings of this study, which were informed
mostly by open data sources, highlight the importance of reviewing historical evidence to
inform sustainable river restoration strategies.
CATMAN: A NATURAL CAPITAL FRAMEWORK BASED ON WHOLE CATCHMENT
MODELLING OF LAND USE, ASSET IMPROVEMENT, DIFFUSE POLLUTION AND
FLOOD RISK
R. NGAI1, R. SMALE2 & S. FOX3 1 JBA Consulting, 2 Vivid Economics, 3 United Utilities
Defra and environmental regulators are increasingly asking key sectors to look at utilising
natural capital approaches and valuation to represent the flow of benefits for investment
decisions in relation to asset or whole catchment management solutions. Consequently,
United Utilities is looking to pilot natural capital approaches in anticipation of more
catchment based approaches. This would include developing an options appraisal process at
a catchment level from a WFD perspective to determine multiple benefits for stakeholders.
JBA Consulting, in partnership with Vivid Economics, was tasked to create a natural capital
decision support model for the Petteril catchment in Cumbria to test and target solutions to
achieve the best value outcomes for the catchment and United Utilities’ customers. A
methodology was created to integrate flood risk and water quality modelling that could be
inputted into a natural capital economic model to appraise a range of risks and benefits across
the catchment. This methodology needs to be transferable and replicable. Fundamentally,
such an appraisal requires integrated modelling of these different catchment risks informed
by expertise from different disciplines from flood and diffuse pollution modelling to carbon
and economic accounting.
The trial of this methodology for the Petteril catchment was largely informed by local
stakeholder consultation. The consultation was essential to gain local knowledge and
information on the Petteril catchment and the types of interventions that can be
implemented. Interventions chosen included asset based approaches and catchment based
approaches including sustainable wastewater treatment works and catchment interventions,
including working with natural processes. Catchment interventions included converting
grassland into woodland areas, soil improvements, and adding runoff attenuation features.
The methodology utilised existing water quality modelling tools. FARMSCOPER was used to
define the percentage change in diffuse load reductions for Nitrate and Phosphate with
subsequent reduction of diffuse load inputs in SIMCAT to compute the percentage change in
load and water quality at key monitoring sites. Additionally, JFlow (JBA’s 2D hydrodynamic
modelling software) was used to investigate the benefits of catchment interventions on flood
risk.
The outputs of this environmental modelling informed the natural capital approach and
valuation to determine the net present value of management options. The natural capital
approach and valuation results are presented in an integrated interface called the CatMan
(Catchment Management) tool. This CatMan tool will support United Utilities and its
stakeholders in determining the optimised solutions providing benefits beyond its fair share,
achieving more for less. It can be populated using outputs from different modelling packages,
and provides an interface for decision makers that takes on multiple benefits.
COMMUNITY MODELLING – SHAPING THE FUTURE OF LONDON RIVERS
R. NELSON1, P. WHITEHEAD2, G. BUSSI2 & C. LANDSTROM2 1 Thames 21, 2 University of Oxford
As environmental pressures increase, the need for creating a sustainable, evidenced based
approach to how governments, NGO’s and stakeholders manage a river is imperative.
Thames21 has worked with local communities to teach previously ‘academic’ techniques
providing communities with empirical evidence to make a difference. The concept of
community modelling and the computer integrated catchment model (INCA) used by
Thames21 was developed by University of Oxford.
Community modelling engages with residents and provides them with the tools to shape the
future of their local rivers. It has been successfully used in Otley, Leeds, to reduce the issue
of flooding. Thames21 and the University of Oxford, have adopted the technique to explore
water quality, bringing together citizens from a variety of walks of life; some with an avid
interest in utilising computer models and others with a desire to improve the environment.
Thames21 recognises the potential of engaging with communities by working collaboratively
to achieve community led decision making. Through disseminating and sharing knowledge of
water quality issues by using the computer model INCA to support decisions at a catchment
scale, communities feel engaged, valued and empowered. The merits of citizen science within
Thames21 has shown how large scale data sets collected by citizens can provide useful
evidence for researches and academics.
Thames21 has worked with 3 community groups in North London to identify sources, test
scenarios and prioritise actions to improve the water quality in each catchment. Acting as a
neutral facilitator, Thames21 created an inclusive engaging environment meeting monthly in
a community space. The groups began by establishing the water quality issues affecting the
catchments, and making decisions on the direction of how to resolve and improve water
quality.
After a series of walkovers and potential site investigations to connect the community with
their local river, various scenarios were tested to ascertain the potential impact caused by the
installation of SuDS among others. INCA was used as a decision support tool to help predict
where the biggest improvements will be witnessed, whilst also providing evidence of how
effective they will be in the future.
Community modelling has successfully demonstrated its’ versatility in use, providing solutions
for flood risk and water quality issues. With the uncertainty surrounding Brexit and as funding
bids become more competitive, the demand for empirical evidence increases, and thus the
need for community engagement. The potential for replication throughout London and the
UK for community modelling projects, across a spectrum to become the forefront of driving
environmental changes is as yet an untapped resource.
Day 2: Wednesday 25th April
Session 5: Workshops Workshop A – A Focus on Floodplains
KEY PLAYERS IN FLOODPLAIN DEGRADATION
S. BENTLEY1, N. ENTWISTLE2 & G. HERITAGE1 1 AECOM, 2 University of Salford
Regime analysis suggests that temperate alluvial watercourses overtop their banks on
average once every 1.5 years transferring water and sediment across the valley floor to form
floodplains. Lateral erosion and deposition also often operates to rework valley floor deposits
creating a variety of floodplain morphologic units in the process which retain a functional
connectivity with the main river. The result is a morphologically and ecologically varied
wetland dominated ecotone whose diversity is maintained by the action and flooding and
shallow groundwater processes. Floodplain areas are, however, sensitive to disruption and
many have been significantly degraded as a result of activities that alter flooding groundwater
processes and manage vegetation communities. Previous studies have highlighted the role of
agriculture in the loss of floodplain. Analysis of floodplain land use for rivers in England since
1990 reveals intense, progressive and near ubiquitous modification of natural floodplain
characteristics. Very little floodplain remains as rough largely uncultivated or wooded areas
with the majority of floodplain surfaces subject to farming pressures. This paper reviews the
progressive loss of natural floodplain in England and investigates the impact that this has had
on natural floodplain functioning, floodplain ecology and flooding regimes.
The review has revealed extensive and severe degradation of our floodplain systems in
England across both upland and lowland areas resulting in an almost complete loss of natural
floodplain functioning. River restoration remains concentrated on in-channel activity,
however, the push for natural flood management offers an opportunity to restore our
floodplains with an associated improvement in ecological value and flood driven functionality.
The research presented here suggests that it is not lack of floodplain storage space in the
upper catchment, rather the decreased efficiency of floodplain areas to retard flow linked to
grazing which is leading to increased downstream flood risk. Floodplain reconnection,
vegetative naturalization and selective grazing reduction are required to begin to restore
upstream floodplain flood function helping alleviate flooding pressure downstream.
MULTI-OBJECTIVE FLOODPLAIN RESTORATION FROM CALIFORNIA, USA
C. BOWLES1 1 cbec eco-engineering
Multi-objective floodplain management (or floodplain management), as it is referred to in the
USA, is an approach that has progressed rapidly over recent years and we have learned much
through practice and experience. As a philosophy, floodplain management aims to remove
barriers to a river’s natural physical and ecological processes that help to promote healthy
riverine ecosystems, as well as providing opportunities for flood risk reduction through
attenuation of flood pulses on the floodplain. Floodplain management as an approach and
philosophy has been practiced in the USA for over 30 years.
This presentation is an update and an extension to a presentation given at the RRC Conference
in Brighton in 2017. Here a more in depth investigation of two large scale floodplain
restoration projects (case studies) will be presented as examples of floodplain restoration in
California, showing the successes and shortcomings of these projects. The first, the Bear River
Levee Setback Project, constructed in 2005, was the first of its kind in California and the
exposed floodplain that has been reconnected to the river now has a flourishing riparian
forest that has established on the frequently inundated floodplain. The multi-benefits of the
project include the increased level of flood protection to the local community and vastly
improved terrestrial and aquatic habitat that has established on the floodplain. Details will be
provided regarding the ecological design of the restored floodplain as well as construction
photos and post construction monitoring and evaluation. Lessons learned will also be
presented.
The second case study that will be presented is the Southport Levee Setback Project in
Sacramento, California. This project is currently under construction. It is unique in its location
and design in California. First, it is a large levee setback project located adjacent to the
Sacramento River between two cities, Sacramento and West Sacramento. Second, the new
setback levee will be constructed from material excavated from the floodplain, resulting in a
reconnected floodplain that will be ten feet (three metres) lower than the existing floodplain
prior to project construction. This is a large amount of excavation and lowering and will result
in a substantially more connected floodplain to the main river, in terms of inundation
frequency, duration and extent. The resultant ecological consequence of this increased
connectivity will be substantial, particularly for juvenile anadromous fish rearing, as well as
riparian forest recruitment. Details will be provided regarding the ecological design criteria
for a variety of species that were developed to evaluate restoration designs, the ecological,
hydrodynamic and morphological modelling utilized through the design, and photos and
videos of current construction.
HIGH IMPACT RIVER AND FLOODPLAIN RESTORATION OF THE HAMPSHIRE AVON NEAR UPAVON
M. ANTHEUNISSE1, P. WELLER1, R. SPENCER2 & L. DAHL1 1 Wiltshire Wildlife Trust, 2 Five Rivers Environmental Consulting
The River Avon in Wiltshire has recently been identified as the most diverse and healthy chalk
stream in England. Still, a significant number of the water bodies making up the catchment of
the Hampshire Avon are failing to achieve WFD targets and the SAC/SSSI is not in a favourable
condition. Historic, unsympathetic river management and maintenance practices (dredging,
straightening) have resulted in parts in a bare, uniform and over-wide river channel that is in
most places disconnected from its natural floodplain.
The Upper Avon near the village of Upavon has been moved to the edge of the floodplain
(18th century) to allow for maximum use as a water meadow. This system has fallen in
disrepair in the early 20th century and most physical evidence has since gone from the
landscape. However, a uniform channel, mostly disconnected from the floodplain and lacking
characteristic chalk stream features remained in place ever since.
In 2016, the Wessex Chalk Streams Project – a partnership between Wessex Water, local
Environment Agency, Natural England, Wiltshire Fisheries Association, Wessex Chalk Streams
& Rivers Trust and lead by Wiltshire Wildlife Trust – embarked on a project to improve this
particular 500m stretch of the River Avon. Based on LIDAR and additional topographical
survey data, a 1d/2d model was created and several scenarios were run to achieve optimum
dimensions, length and gradient of a channel at the lowest point of the floodplain.
Before the work could start, a Full Planning Permit, a Bespoke Environmental Permit for Flood
Risk Activities, an Archaeological Watching Brief and a Conservation Licence had to be in
place. The latter to make sure not to be in breach of the 1981 Countryside & Wildlife Act due
to the presence of water voles on site.
In September and October of 2017, a new channel according to the model specification was
excavated, with additional wood and gravel introduced. A key challenge during delivery
turned out to be the lack of appropriate sized gravel on site to recreate a stable river bed and
spawning riffles. Additional gravel had to be imported to overcome this.
Further to work on the channel, the floodplain was lowered by on average 300mm, up to 100
meters wide. Following the contracting work, volunteers planted 0.5 ha of native floodplain
woodland as well as bank-side trees to help with generating future natural woody material.
The development of the new channel morphology, as well as (re)colonization by flora and
fauna will be monitored in the years to come by volunteers and the local fishing syndicate.
This project was funded by the Environment Agency and Natural England as part of the River
Avon Restoration Plan, the winner of the 2017 UK Riverprize.
Workshop B – Large Wood in Rivers
THE INFLUENCE OF LARGE WOODY DAMS ON SEDIMENT DYNAMICS M. C. McPARLAND1 & J. HOOKE1
1 The University of Liverpool
A widely used technique for Natural Flood Management (NFM) is to construct Large Woody
Dams (LWDs) in a river to slow the flow of water and create flood water storage areas.
Research on LWDs has typically focused on quantifying the contribution LWDs make to
attenuating flooding by modelling changes to a streams hydrograph or assessing changes to
hydraulics. Multiple papers have demonstrated that LWDs reduce peak mean discharge, delay
time to peak discharge and lower flow velocity. However, research has tended to overlook
how LWDs can affect sediment dynamics.
Due to the limited amount of literature on this topic, analogous research on naturally
occurring Woody Debris Dams (WDDs) was used to assess what changes to sedimentary
processes might be caused by LWDs. WDDs have been shown to cause drastically increased
rates of sediment deposition and have induced large amounts of erosion and scour, with
streams having cut paths around the woody debris, bypassing the obstruction. If LWDs
similarly affect sediment dynamics then these changes could potentially feedback and alter
their effectiveness. Such geomorphological changes are currently not accounted for in the
planning or design of LWDs, and it represents a degree of negative risk for this NFM technique,
with negative risk being defined as factors that inhibit a project’s ability to achieve its targets
or objectives.
To assess the effects that LWDs have on sediment dynamics, post-project monitoring was
carried out on a set of LWDs that were installed on a small steam in Northwest England.
Monitoring involved conducting repeat cross section surveys and terrestrial laser scans, taking
sediment samples as well as in-situ monitoring of flow velocity and crest stage. This data was
also used as the basis for developing a two-dimensional model that assesses changes to
sedimentary processes based on the Bagnold sediment transport equations. The equations
have been solved deterministically and using interval analysis to quantify uncertainty from
which risk can be calculated.
A number of significant changes have already been observed. There has been a large amount
of sediment deposited in the channel immediately upstream of the LWD, reducing the
capacity of the flood water storage area and creating a channel constriction. The constriction
has accelerated the flow of water as it approaches the dam, causing erosion of the stream
bed, allowing the flow to undercut the LWD. These factors have contributed to lessening the
effectiveness of the LWD.
The model that has been created to predict these changes has been developed so that it can
be applied to LWDs that have been constructed in a range of different streams. As such, a tool
is presented that can be used to model how the changes to channel hydraulics induced by a
LWD can alter sedimentary processes. Associated uncertainties can also be calculated,
allowing risks to be evaluated.
THE IMPACT OF WOOD ON BENTHIC AND HYPORHEIC INVERTEBRATES C. MAGLIOZZI1, R. GRABOWSKI1, A. ROBERTSON2 & M. JANES3
1 Cranfield Water Science Institute, Cranfield University, 2 Centre for Research in Ecology, Department of Life Sciences, University of Roehampton, 3 the River Restoration Centre
Large wood (10 cm diameter and 1 m long- LW) is a key element of river channels and one of
its hypothesised benefits is an increase of hyporheic exchange flow which drives ecological
diversity. However, this connection has not been well evidenced in empirical studies of
hyporheic invertebrates. This study examined the effects of submerged, channel-spanning LW
on the hyporheic and benthic invertebrate communities. Invertebrates were surveyed
seasonally in the Hammer stream (UK) along with measurements of streamflow, sediment
size, water chemistry and wood morphology. Results show that LW produces consistent
patterns of habitat variability within the reaches. Such effects were more visible in the sandy
reach, where wood represents the main source of in-channel structural complexity. Results
of invertebrates’ diversity, abundance and biomass will be presented. This study is improving
our scientific understanding of how wood impacts on biological communities.
PRACTICAL ASPECTS OF USING LARGE WOOD IN RIVER RESTORATION & CHANNEL MANAGEMENT
D. HOLLAND1 1 Salix
Large wood can be used to create multiple benefits in watercourses, however
practical issues can reduce the potential applications and limit successful delivery. Using
several case studies the best methods to anchor wood in the long term are considered as is
how to introduce wood into artificial high energy channels. Case studies will look different
large wood techniques based on range of differing risks and energy (River Rhiw Channel
stabilization, Cwmparc large wood scheme, West Newton Bridge). The River Rhiw is a high
energy river in Mid Wales and in 2013 underwent 8m of dramatic bank erosion that exposed
the main high pressure gas pipeline into mid Wales. A combination of large wood bank
revetments, tree deflectors and in channel large wood structures were installed to manage
bank erosion rates and subsequently reduce the rate of plan form adjustment. At Cwmparc
land reclamation works had created an artificial blockstone lined channel network that lacked
any geomorphic variability and accelerated flows down the valley towards urban areas. A
reach scale trial was undertaken to fix large wood structures into the artificial channel in order
to retain coarse bed load that would otherwise be lost downstream. The project aimed to
demonstrate that retaining large wood in such an artificial channel as practical and that
bedlam could be retained in the reach. Sourcing of suitable wood is discussed as well as key
design and installation lessons learned.
Workshop C – River Restoration for Biodiversity
RESTORING FRESHWATER MUSSEL RIVERS C. GIBSON1, R. A. SWEETING1, C. WEST2, M. WEST3, S. HIRST4 & I. MOSER5
1 Freshwater Biological Association 2 West Cumbria Rivers Trust, 3 South Cumbria Rivers Trust, 4 North York Moors National Park, 5 Devon Wildlife Trust
The Freshwater Pearl Mussel (FPM), Margaritifera margaritifera is critically endangered (IUCN
2011), in decline throughout its range and currently protected by the Habitat’s Directive. It is
long-lived with a complex lifecycle; the parasitic larval stage (glochidia) requiring specific host-
fish and pedal-feeding juveniles requiring pristine gravels.
In high numbers FPM have a natural capital role to play through filtering water, cleaning the
water column and stabilising river beds. River restoration requires clear validation. FPM and
its reliance on salmonids provide a useful long-term case study.
The Freshwater Biological Association (FBA) has spent 10 years running and improving an Ark
to conserve adult FPM and augment populations through its captive-rearing system. A recent
3 year national river restoration project has brought delivery and statutory advisory partners
together to raise awareness of the plight of FPM and improve FPM river conditions towards
reintroducing juvenile mussels to their native rivers.
This paper discusses the design of a short-term project requiring annualised deliverables
alongside the wider catchment and historic considerations as well as presenting monitoring
requirements for the reintroduced juveniles.
It describes how FPM river restoration has been prioritised through surveying, studying water
quality and assessing suitable habitat availability for both FPM and salmonids. In some cases
reintroduction sites have been identified and improved ready to receive juveniles captive-
reared at the FBA Ark. The engagement of local funders, land managers, volunteers and
experts has been utilised throughout towards gaining trust, permission, understanding in
business benefit, ‘mussel-power’ and achieving wider catchment benefits.
In spring 2017 seventy 8 year old juvenile FPM were reintroduced into their native river.
These juveniles, reared in a controlled system, were first conditioned in a bespoke-designed
flume and their behaviour to water flow, gravel and diurnal variation studied. The
reintroduction site was chosen for water quality, gravel sheer stress and access for
monitoring. Despite expert advice and careful consideration this remained nerve-wracking
and provided surprises. Maximisation of learning from this step and ideas for improving
monitoring of survival are also considered. A local captive-breeding system has also been set
up providing interesting comparison.
UNDERSTANDING HISTORIC CHANGE AND USING NATURAL PROCESSES TO INFORM FUTURE DECISION MAKING
M. HEMSWORTH1 & S. ROSE1 1 JBA Consulting
Too often flood risk management schemes have been implemented with little regard for
historic catchment change or understanding. A traditional engineering approach has
frequently been applied, walls have been built, channels straightened and the flooding
problem has been pushed elsewhere. Case studies will be described where past river works
have had an engineered form with little consideration of historic catchment change or existing
river processes. We will describe examples where channel straightening has caused significant
loss of channel length and subsequent morphological change and floodplain disconnection.
Any form of river works undertaken to manage flood risk need to understand catchment wide
processes and flow regimes. Crucially, an understanding of how the channel has been
modified over time will improve our understanding of existing channel processes and
responses, which should be used to inform future restoration and flood risk management
schemes. Several examples will be presented where an understanding of historic channel
planform change can be used to inform river restoration and be combined with natural flood
management methods in order to reduce flood risk.
This approach not only has the benefit of restoring and improving natural geomorphic
processes and reinstating natural channel and floodplain form and function, but it has the
added benefit of reducing the need for complex and costly engineering schemes in small rural
villages within catchments with high flood frequencies.
This presentation uses recent examples from across the UK to discuss the lessons learned to
date, potential cost implications and savings, together with the challenges ahead to overcome
the engineering barrier in order make this approach more attractive to landowners and
regulators.
Workshop D – Natural Capital and Ecosystem Services: Accounting for
Benefits
MONETISING ENVIRONMENTAL BENEFITS – THREE CASE STUDIES A. PETTIT1 & C. ANDERTON1
1 JBA Consulting
In a world of restricted budgets and competition for limited funds, the ability to demonstrate
that your project costs are outweighed by the benefits, in addition to achieving the stated
aims and wider benefits, is becoming ever more important. Whilst there are a multitude of
techniques available to consider and qualify project aims and any wider social/environmental
benefits, the failure to quantify the monetary benefits of restoration projects can risk
underselling a business case. We will present practical applications into the monetisation of
environmental benefits for three quite different environmental improvement projects:
Natural Flood Management study for the Yoker and Duntochter Burns in Greater Glasgow
Scotland, driven by the Scottish Flood Risk Management Act 2009 and comprised of two
neighbouring catchments, one an essentially rural catchment and the other an urban
catchment. This case study illustrates the use of widely available socio-environmental
benefits that allowed us to evaluate the potential benefits of the proposed NFM and
compare alternative sites. The study included benefits associated with flood damages,
habitat creation benefits, carbon sequestration, recreational and amenity benefits and
property premiums.
Managed realignment study in Wales where the benefits of habitat creation were
assessed to determine whether more managed approaches to the realignment were valid
and cost effective. The study used an ecosystem services approach to qualify the impacts,
with monetary values assigned to biodiversity gains, food services and climate regulation.
Dis-benefits associated with the loss of farm rent were also incorporated.
A theoretical forestry planting study in Nottinghamshire was used to compare typical
flood benefits of NFM against the wider environmental benefits. Reviews of academic and
grey literature, combined with value transfer approaches were used to assign monetary
benefits to the carbon sequestration of woodland, amenity and recreational benefits,
biodiversity and habitat gains and economic employment benefits. The research showed
that the inclusion of environmental benefits significantly helped to justify the proposals
and were essential when land compensation costs were included within the analysis.
We will highlight practical tools and applications for these three diverse projects and illustrate
the types of benefits that can easily be valued and incorporated within a benefit-cost
assessment or to assist with obtaining partnership funding. The impact of the inclusion (or
exclusion) of these environmental benefits will also be discussed.
WHAT HAVE WETLANDS EVER DONE FOR US? M. BARKER1 & D. GASCA1
1 Atkins Global
What ecosystem services do wetlands provide us with? How can we communicate their value
to an external audience? Should we invest in restoring degraded wetlands or creating new
ones? And how can we unlock funding to create more of what we want? These are all
questions that natural capital valuation can help us answer.
Whilst for many environmentalists the concept of natural capital creates a philosophical
dilemma, the approach provides a common and understandable language that can be used
to evaluate and communicate the benefits natural systems provide to society. The science
behind natural capital, however, is very much in its infancy. There are a number of
complementary and alternative approaches and tools to estimate the value of natural capital.
Formal assessments that fully reflect all ecosystem services can also require time intensive
and costly data collection.
This paper will present a framework for assessment designed for use as part of river and
wetland ecosystems that are located in different landscape settings, provide different
functions for local communities and have been funded by different stakeholder groups,
including government agencies, environmental charities and water companies.
We will discuss the use of natural capital valuation in demonstrating the impact of Camley
Street Natural Park, an urban wetland 1ha in size located in King’s Cross, London. Our
valuation study revealed that Camley Street Natural Park, which is managed by the London
Wildlife Trust, contributes a value of £2.8million to the local economy and society annually.
The Natural Capital valuation enabled London Wildlife Trust to take the first steps in securing
Camley Street’s future. The study was a key piece of evidence for a large, successful capital
fundraising strategy to construct new visitor facilities at the Park, ensuring the park’s legacy
and supporting the sustainable development of the Kings Cross area through delivery of
ecological and social benefits in a rapidly developing part of the city.
We will contrast this urban natural capital valuation with examples from more rural sites,
including Medmerry Managed Realignment Scheme. This has created 184 hectares of new
wetland habitat, now managed as a nature reserve that is delivering biodiversity, flood
defence, recreation and carbon sequestration. An in-depth value transfer study of this coastal
site estimated the net natural capital value of the scheme to be around £3.0million per year.
The paper will also consider potential ways of collecting some of the detailed social data that
are required to complete robust assessments. For example, how do we value the worth of
educational visits? How can we measure the flow of people to, from and through such
wetland sites? And how far do they come to visit them? These types of assessments require
sophisticated and innovative evaluation techniques and some pilot studies will be presented.
Session 6: Parallel Sessions Conference Theatre: Natural Processes and Morphological Adjustment
THE IMPORTANCE OF DECADAL SCALE MORPHOLOGICAL CHANGE IN FLOOD RISK MANAGEMENT - THE CASHEN ESTUARY, COUNTY KERRY
C. BARRETT-MOLD1 1 Black & Veatch
This presentation examines the importance of understanding the historical morphological
evolution and processes acting in an estuarine system over decadal timescales when
assessing management for flood risk.
The Cashen Estuary (County Kerry) is typical of the sediment rich, highly dynamic, bedrock
embayed coastline of western Ireland. The wider Cashen/River Feale Catchment is
predominantly agricultural and is managed with an extensive artificial drainage network and
polder system. In order to minimise the duration of flood water on the surrounding land the
main river channel has been historically dredged to maintain effective drainage.
As part of a review of the current flood risk management in the catchment the Office of Public
Works (OPW) commissioned Black & Veatch (BV) to undertake a conceptual
hydromorphological study of the estuary to inform future management decisions. The study
used historic maps and survey information together with present day site surveys, sediment
sampling and hydrological modelling to characterise the current hydromorphology of the
estuary and assess its evolution to the present state. This information was then used to inform
an options appraisal of future flood risk management in the catchment.
Analysis of historical information available identified a relatively rapid progradation of the
dunes at the mouth of the estuary approximately 160 years ago. This resulted in a constriction
that had the effect of throttling and increasing the period of the ebb tide with consequent
impacts on sedimentation and the hydrology of the estuary. Interrogation of the historic
mapping also identified a reduction in the elevation on the polders most likely due to the
improved drainage of the area; this too has had a significant impact on period of flood
inundation of the area. The identification of these key controls has meant that informed
management options can be proposed that are effective and sustainable in the long-term.
LET THE RIVER ERODE! GIVING A GRAVEL-BED RIVER BACK ITS FREEDOM SPACE…WHAT DO YOU GET?
R. WILLIAMS1, H. MOIR2, J. WHEATON3 & E. GILLIES4 1 University of Glasgow, 2 cbec eco-engineering UK Ltd & University of the Highlands and Islands, 3 Utah State
University, 4 cbec eco-engineering UK Ltd & University of Glasgow
River restoration practice is stuck in confusion about the concept of geomorphological
“stability”. There is a tendency to interpret “stability” as “static” and to thus promote
restoration designs that create & maintain a prescribed morphology. Resilient river systems
typically adjust their morphology; such systems yield the much more spatially and temporally
diverse, and productive habitats that are often the aim of restoration interventions. However,
restoration practitioners & managers don’t always identify “increased dynamism” as a design
objective and rarely “let the river do the work”. Broadly, there is irrational fear of channel
adjustment and a misunderstanding of the role that natural bank erosion plays in both
providing important local sediment supply and building diverse instream habitat. Such fear
has been accentuated by a lack of objective approaches to systematically quantify river
morphology & habitat to provide a necessary evidence base. One glimmer of hope, is that
high resolution topographic (HRT) surveys that capture river morphology before and after
restoration are proliferating, enabling the mapping and quantification of patterns of erosion
and deposition. However, such approaches to interpreting topographic change tell us little
about how habitat has been shaped. More traditional, field based approaches to mapping
morphology &habitat are always subjective, with high potential for ‘operator variance’ that
makes repeat surveys virtually quantitatively worthless.
This presentation will answer the question: “if we restore bank erosion & sediment transport
to what was once a dynamic, wandering gravel-bed river, do we get more diverse in-channel
habitat?” We use a series of before & after HRT surveys acquired from one river restoration
scheme (Allt Lorgy, Scotland) to systematically map a time-series of geomorphic unit (GU)
mosaics, using new GU Toolbox (GUT) software. This software implements topographic
definitions to discriminate between a taxonomy of fluvial landforms that have been
developed from an extension of the River Styles framework. There are three tiers of
processing: (1) differentiation between in-channel deposits & overbank areas; (2) classifying
form into one of six categories (mound, bowl, trough, saddle, plane, wall); & (3) mapping GUs
based on a range of attributes such as position & orientation.
Consistent GU mapping shows that restoration of Allt Lorgy has created a rich assemblage of
GU diversity. Results show that once bank protection is removed & sediment supply
augmented, active bank erosion enables the formation of lateral and point bars, diagonal bar
complexes, and instream wood creates forced plunge pools & riffles. This presentation
provides: (i) the first systematic quantification of how geomorphic unit diversity increases
when a gravel-bed river is given freedom space; (ii) a framework for using HRT surveys to test
design hypotheses & conceptual ideas associated with process-based restoration.
SEDIMENT AND MANAGED NATURALIASTION: RESULTS FROM THE MONITORING OF SWINDALE BECK
G. HERITAGE1, L. SCHOFIELD2 & N. ENTWISTLE3 1 AECOM, 2 RSPB, 3 University of Salford
Restoration of rivers in the UK has undergone a significant change over the last decade with
approaches moving away from structural intervention in the form of deflectors and green
bank protection to control unwanted erosion, through to channel and floodplain modification
that is in line with current fluvial processes to increase the chances of longer term success.
The recognition that a river can do a lot of the restoration work itself has become recognised
and river naturalisation, where minimal targeted intervention is designed to rejuvenate fluvial
features and processes, has become a popular approach to improving our river and floodplain
systems. Here we review the short term (18 months) response of Swindale Beck, an active
upland gravel bed river in the English Lake District, to naturalisation. Monitoring of the site
has occurred following works on almost 3 km of watercourse, changing the system from a
straight revetted plane bed system to a mixed, pool-rapid and sinuous single thread system
strongly connected to its former floodplain.
The monitoring programme has measured erosional and depositional processes at the site
using repeat sUAV survey revealing an initial rapid adjustment to the imposed river template,
flushing of exposed silts and redistribution of finer bedload followed by a period of reduced
activity directional change in line with that anticipated for an active sinuous single thread
channel. Coarse sediment movement is seen to be integrated with the embryonic bar forms
to produce a river in dynamic equilibrium with an undisrupted bedload transport regime and
no significant morphological change has been recorded downstream following the initial flush
of finer gravels.
Fine sediment releases occurred as pulses for some time following the works resulting in
significantly elevated suspended loads being released downstream. It is particularly
interesting to note, however, that the bulk gravel monitoring sites located downstream did
not show increases in the volume of fines present in the bed. This suggests that the
downstream monitored reach is a high enough energy system to be robust to
sedimentological change and potentially too that the overall mass of fine sediment was small
enough to be integrated into the wider sediment transport regime.
HOW DO WE PROPERLY IMPLEMENT THE PROCESS-BASED RIVER RESTORATION APPROACH?
H. MOIR1 & E. GILLIES2 1 cbec eco-engineering UK Ltd and Highlands and Islands University, 2 cbec eco-engineering UK Ltd and
University of Glasgow
For practical reasons, individual river restoration projects often involve a limited number of
design components; for example, embankment removal/ set-back, channel realignment,
gravel augmentation, large wood placement, wetland establishment/ enhancement etc. For
the same reasons, they also tend to be limited in spatial extents (longitudinally and laterally).
Due to such issues, the application of the ‘process-based’ approach to river restoration is
limited; the factors that are impacting the fundamental controls on physical process cannot
be sufficiently addressed. Ideally, all factors that are affecting the supply, transport and
storage of water, sediments and large wood should be identified and their influence removed
or reduced through appropriate design and implemented measures. Often these fundamental
impacts are manifest out-with the specific river reach where the perceived problem exists.
We present information from a large-scale river restoration project in the headwaters of the
River Nairn, Highland. At the downstream limit of the study site, >60% of the mainstem river
is within the domain of the restoration project; as such, this represents a genuine practical
example of a catchment-scale project. The river had historically been straightened, dredged
and embanked, with the channel becoming significantly perched above its floodplain and
resulting in significant flooding and field drainage issues. The restoration approach was
fundamentally process-based; the root causes of impacts to geomorphic condition were
identified and specific restoration measures applied with the aim of reinstating natural
physical processes, within the practical limitations of site constraint. To achieve this aim,
specific design elements included the realignment of 1.5 km of channel (providing a ‘proto-
channel’ for geomorphic processes to adjust to an equilibrium state), >7000 m3 gravel
augmentation, the placement of 18 large wood structures, >2.5 km embankment removal and
the development of three ‘online’ wetland areas.
The development of the wetland areas represents an especially important restoration
component, in terms of restoration in a UK context. Human intervention has resulted in most
rivers becoming simplified, single-thread channels with the associated loss of physical
complexity and, specifically, wetlands. The impact of this to biological productivity/ diversity
has not been quantified but will be considerable. Specifically, wetlands provide ‘hotspots’ of
nutrient storage and ‘low energy’ physical habitat conditions; both factors are important for
biological productivity.
Post-implementation monitoring of the project is underway; repeat topographical and
sediment surveys reveal rapid channel adjustment towards increased complexity, especially
close to large wood structures. Furthermore, existing biological data (invertebrate samples,
electro-fishing surveys, redd counts) provide a baseline for measurement of the ecological
response to the scheme.
Conference Suite 2: Approaches to Planning and Implementation
RIVER RESTORATION WIPEOUT D. HAMMOND1 & S. WHITTON1
1 Affinity Water
You will all have seen presentations about successful river restoration projects, but what you
may not know is some of the detail behind achieving the final product. The path to success is
often as tricky to navigate as walking up an algae-covered rock-ramp in the dark and you are
guaranteed to get your feet wet, if not more. So, just when you thought it was safe to proceed
along the narrow, slippery path towards your goal, yet another issue or bit of bureaucracy
swings in from the side, knocks you off your feet and sends you back a few places – maybe
back to the Start.
Hazards to negotiate could include:
Landowner/project partner fickleness
Multiple stakeholders with conflicting advice or requirements
Inexperienced regulatory staff lacking pragmatism and sticking to the letter of the policy
Issues with land ownership and designations, such as dealing with Common Land and
“stopping up”, the transfer of land within a local authority from Highways to another
department
Site issues such as buried WW2 bunkers, bombs, Anglo-Saxon graves, unmarked utilities
and even issues with known utilities
Ecology and, in particular, protected species
Local Friends (or should that be “Fiends”?) groups
This presentation aims to illustrate some of these issues and to suggest useful ways to
negotiate your way through the River Restoration Wipeout Course.
ALIEN INVADERS AHEAD! - ARE YOU WATCHING OUT FOR THEM? P. ALDOUS1
1 Thomson Ecology Ltd
Legislation now exists around the control and management of invasive non-native species
(INNS) such as the Infrastructure Act 2015. Whilst these regulations aim to prevent the
introduction of INNS, eradicate their presence after detection and containment if eradication
is not feasible, liabilities exist if INNS are transferred onto third party land. With the cost of
INNS management to the UK of £1.7b everyone needs to play in managing and protecting the
environment from the spread of INNS. Many businesses have adopted biosecurity policies
whether that be in response to foot and mouth, BSE or INNS. But in practice are these
rigorously followed and have the water environment supply chain fully understood the risks
and responded appropriately. Either there is a wakeup call or good news story ahead. This
paper raises awareness of the INNS issue to all participants in river restoration and the
activities that they either individually can take or can apply to the supply chain to ensure that
INNS are not inadvertently spread across the UK.
SOUTH CALDER WATER - CHALLENGES IN URBAN RIVER RESTORATION
C. PITTNER1 1 WSP
SEPA and North Lanarkshire Council, embarked on an ambitious project to restore a reach of
the South Calder Water flowing through Shotts, North Lanarkshire. The South Calder Water
flows through the southeast margins of Shotts through artificial channels and culverts
emerging in natural open channel south of the town. Shotts has a rich industrial history of
coal mining and iron works, spanning 145 years from 1802. Lack of regulation in waste
disposal throughout this industrial period led to significant contamination of surrounding
public open spaces and the water environment. The objectives of the project were to restore
the river to improve ecological potential, and break the pollutant linkage with the
watercourse to improve water quality creating an environment where the local community
can enjoy and interact with a revived waterbody. The presentation will cover the
methodology and process of restored option selection, with particular focus on the many
challenges faced including contamination, mine workings, utilities, topography, restricted
working area, land ownerships, public interface and anti-social behaviour and how each of
these were overcome and managed in the design and delivery of the project.
EROSION RISK SCREENING IN ENGINEERING DESIGN ON MAJOR INFRASTRUCTURE PROJECTS
H. PARSONS1, K. KEMBLE1 & S. ROBERTS1 1 Jacobs
Changing perception of river engineering solutions to major infrastructure developments
poses not only one of our biggest challenges but also some of our biggest opportunities.
Following decades of engineering rivers to suit infrastructure design, through current
legislation we hold the power to influence design to reduce environmental impacts upon our
watercourses and deliver improvements and mitigation through design. Whilst this change of
approach to designing infrastructure and river engineering is taking greater account of fluvial
geomorphology, its wider catchment impacts and interrelationships with other disciplines,
such as ecology, geotechnical and landscape, incorporating fluvial geomorphology into design
is still often seem as something that can be ‘worked around’. Thus, it often takes bold moves
to influence engineering design at the early stages of projects. Often, drastic design solutions
voiced and immediately dismissed around the design table, become the preferred design
solution. This presentation provides examples of extreme design solutions to major
infrastructure projects that delivers not only benefits to the fluvial functioning of the river but
also provides significant benefits including: improvements to SAC, SSSIs, floodplain
connectivity, water quality, flood risk, river ecology and WFD water body improvements.
Some major infrastructure projects, in particular upgrades to existing infrastructure, carry
with them existing constraints on the fluvial functioning of our rivers, and/or the proximity of
the existing infrastructure is at risk from the fluvial dynamics of the river system, which
potentially puts both life and property at critical risk. Such design solutions pose significant
challenges. This is exacerbated when the watercourses hold designations such as SAC, SSSIs
etc. Where existing infrastructure requiring upgrade, such as road widening, occurs alongside
active river channels, erosion risk often poses a major threat to the existing and future asset.
Erosion control measures often require intrusive engineering and bank and bed stabilisation
measures, such as large boulders along the bank face and buried within the channel to protect
from scour. Where a Habitat Regulations Assessment (HRA) is required, such design solutions
are unlikely to comply with the HRA. Thus alternative design options need to be sought, which
may involve bold suggestions such as off-line solutions.
Through this work, investigations into river bank erosion risk is becoming an accepted part of
the scoping phase of major infrastructure projects. By voicing bold design options, such as,
‘move the road’ numerous cross-discipline environmental and infrastructure benefits have
been delivered on major projects. Furthermore, through influence in design,
geomorphologists are compiling a portfolio of case studies to promote the benefits we deliver
in engineering design thus improving our power of influence on future projects.
Conference Suite 3: Catchment Scale Thinking
IMPROVING NATURAL FUNCTIONING AT THE CATCHMENT SCALE L. WEBB1
1 Natural England, Catchment Sensitive Farming
This presentation explores the range of measures that have been delivered through
Catchment Sensitive Farming and considers their role in catalysing improved hydrological
function at the wider catchment scale. Integrated delivery for water quality and flood risk has
been trialled in pilot catchments. Lessons learnt from these catchments will be shared using
case study examples. The need to ensure the whole catchment's function is considered when
developing a river restoration programme will be raised and questions will be posed on how
to improve the links between this work and river restoration programmes.
RIVERLANDS - EXPLORING PEOPLE'S CONNECTIONS TO RIVERS AS A CATALYST FOR CHANGE
R. HIGGS1 1 National Trust
Riverlands - Healthy rivers and catchments, rich in wildlife, enjoyed and cared for by all.
Only 17% of England’s rivers are in good health, as intensive agriculture, development
pressures and the effects of climate change take their toll, and 13% of freshwater and wetland
species are now threatened with extinction from Britain. Solving this problem requires a
catchment-scale approach with people and organisations working in partnership. We think
it will only be by connecting people with their rivers and surrounding area that there will be
sustainable change and long term benefits.
Riverlands is a programme of work led by a national partnership of the National Trust, the
Environment Agency and Natural Resources Wales, and will take place in eleven catchments
in England and Wales, and the first phase of work will concentrate on the following seven:
The Upper Bure (Norfolk), The Upper Conwy (North Wales), The Derwent (Cumbria), The
Poulter (Nottinghamshire), The Doe Lea (Derbyshire), Porlock Vale streams (Somerset), The
Bollin (Cheshire).
The programme has three main aims:
1. Rivers and catchments that are healthy, clean and rich in wildlife
Improved water quality and habitat diversity
Key species recovery in progress
Increased area of valuable habitat
2. Rivers and catchments that are easily accessed, valued and loved for their heritage and
beauty
More people are able to access and enjoy rivers and the surrounding area
More people understand and are inspired by the role rivers play in their lives – past,
present and future
More people have the opportunity to make a difference to the long term care of rivers
and catchments
3. Sustainable long term care for river catchments that has a national impact
Better informed and shared land management practices at a catchment scale that
benefit nature
Better management of flood risk
Improved approach to working in partnership to deliver long term care
People are empowered to take greater ownership of the long term care of the
catchments
Riverlands covers the rivers themselves, the land that drains into them, and the species and
habitats that exist within the catchments. It will also focus on the cultural heritage of the river
catchments, including the ties that have bound people to the rivers in the past, the way that
people’s lives have been influenced by rivers and the surrounding land, and the traditions that
have arisen in relation to the rivers. A programme approach will give this work real impact on
a national scale.
Our approach is to start by exploring people’s connections rivers: as neighbours, users,
visitors or landowners. Through this we will find partners, advocates and supporters and from
there will flow land use change and local ownership. The programme will start in 2018 and
this first phase will be completed in 2024.
ARE WE ACHIEVING INTEGRATED CATCHMENT MANAGEMENT IN PRACTICE? E. D. ROLLASON1, L. J. BRACKEN1, R. J. HARDY1 & A. R. G. LARGE2
1 Durham University, 2 Newcastle University
The principles of Integrated Catchment Management (ICM) are increasingly embedded into
catchment management policy in England and Wales. This has resulted in the need for
community engagement at all levels of catchment intervention, from the development of
catchment management plans to the implementation of individual management
interventions. However, previous research has demonstrated the difficulties of achieving
meaningful participation at scale and has highlighted how ordinary catchment management
continues to predominate in many cases despite the policy shift.
This research explores how ICM is undertaken in practice, using the example of the Greening
the Twizell Partnership, an innovative catchment partnership established in the Twizell Burn
catchment, a tributary of the River Wear in NE England, to explore wide ranging
environmental and socio-economic catchment interventions. Through participation in the
activities of the catchment partnership, and participatory research with communities within
the catchment, the research explores how ICM interventions are enacted in practice, and how
these are experienced by the communities. The research finds that at a catchment level,
limited engagement with communities is undertaken to shape the direction of catchment
management activities. However, in the planning and implementation of works the research
finds that our existing practices of project development and funding are not flexible enough
to allow project scopes to be (re-)shaped by local concerns or priorities, leading to
engagement activities being avoided or ignored until after projects have been planned and
funding obtained. In addition, the fragmentation of responsibilities for catchment
management between many agencies means that information about local concerns or
priorities identified in one project is often not transferred between agencies, meaning that
communities experience ICM not as an integrated process but as a fragmented series of
apparently disconnected interventions delivered by different agencies.
The research demonstrates that the principles of ICM have the potential to deliver more
effective and unified catchment management. However, although catchment management
policy has been effectively developed to enshrine these principles, there is a pressing need to
determine how our practices of catchment management can be made more flexible to
integrate local community concerns and priorities more effectively.
NETWORK TOPOLOGY: THE "MISSING LINK" IN UNDERSTANDING CATCHMENT CONTROLS ON INSTREAM HABITATS?
E. L. HEASLEY1, N. J. CLIFFORD2, J. D. A. MILLINGTON1 & M. A. CHADWICK1 1 Kings College London, 2 Loughborough University
The structure of the river network, or network topology, is a fundamental feature of the
catchment linking catchment-level controls to instream functioning. In particular, confluences
in the network have been shown to induce morphological and ecological changes in channels
due to inputs of water and sediment from incoming tributaries. Yet river topology is often
either over-simplified or ignored by catchment-scale assessments, despite variation in the
density of the river network within catchments. This presentation asks to what extent the
density of the river network influences instream habitat diversity.
Original research is presented that uses data from the River Habitat Survey to identify how
instream habitat diversity is impacted by the spatial position and characteristics of
confluences in the river network. We will also introduce a new tool to account for network
topology, named Network Density, which was designed to be easily calculated using GIS for
any catchment. Network Density is shown to offer better explanations of habitat diversity
scores than the simplistic stream order variable.
The new approach is applied to the Demonstration Test Catchments (Hampshire Avon, Eden,
Tamar and Wensum). The results illustrate how habitat diversity generally increases as the
network becomes denser, and how low-energy confluences impact habitat diversity most.
Finally, the presentation discusses how including network topology in catchment-scale
assessments may improve our ability to predict which sections of the river network may
sustain naturally higher habitat diversity and which tributary inputs at confluences drive
heightened habitat diversity. This could enable more strategic targeting for sustainable river
restoration and potentially target conservation of flows on tributaries that impact instream
habitat diversity.
Session 7: Conference Theatre
INCISED LOWLAND SAND-BED STREAMS IN THE NETHERLANDS K. C. HUISING1, R. C. M. VERDONSCHOT2 & M. VELDHUIS1
1 Waterboard Vallei en Veluwe, 2 Wageningen Environmental Research
In many lowland streams in Northwestern Europe the number and the magnitude of peak
discharges increased due to land use changes and climate change. This often leads to channel
incision and degradation of the stream ecosystem. One of those streams is the Leuvenumse
beek in the Netherlands. Here, the Waterboard Vallei en Veluwe and the nature conservation
agency Natuurmonumenten are trying to restore the stream by artificially supplying sand to
the stream, creating sand slugs which elevate the streambed and reconnect the stream with
its original riparian zone. The sand is supplied from 15 locations along 6 kilometres of the
stream and dispersed by the stream naturally. This according to the ‘Building with Nature’
principles. Besides this, large woody debris were placed in the stream to prevent new incision.
To assess the impact of this restoration measure on the stream ecosystem, bed morphology,
substrate heterogeneity, macroinvertebrate assemblage structure and riparian vegetation
composition were monitored since the start of the measures in 2014. After recovery from the
initial disturbance, an increase in instream microhabitat heterogeneity and current velocity
was observed, which was also reflected in the macroinvertebrate community recorded.
Rewetting of the riparian zone resulted in the establishment of fringe of marsh vegetation
along the stream margins. In conclusion, locally supplying sand to incised lowland streams has
resulted in noticeable short-term ecological effects, indicating the potential of this rarely
applied restoration measure.
RESTORING UK CATCHMENT SCALE BIODIVERSITY - RIVERS, LAKES, PONDS AND WETLANDS
S. J. CLARKE1 1 National Trust
We are increasingly recognising the need to view river restoration at greater spatial scales,
placing reach scale restoration in the context of both upstream and downstream reaches and
the wider catchment. Addressing the needs of freshwater wildlife requires this and more. I
will explore how we might look across the range of different freshwater habitats to take a
catchment or landscape scale approach to freshwater conservation. Using examples from
completed and ongoing National Trust projects, I will show how a greater understanding of
the ecology of key species and the interactions of stressors might help us develop better
approaches.