Bath and North East Somerset – The place to live, work and visit

BATH RIVER AVON

OPTIONS APPRAISAL

Stakeholder Workshop

15 October 2014

B&NES Council

Environment Agency

GBV JV Ltd

Bath and North East Somerset – The place to live, work and visit

Welcome

Councillor Ben Stevens

Cabinet Member for

Sustainable Development

B&NES Council

Bath and North East Somerset – The place to live, work and visit

Introduction

1 CONTEXT Simon Martin B&NES

2 PULTENEY & TWERTON GATES Melvin Wood & Nigel Smith EA

3 OPTIONS PRESENTATION Andy Wallis GBV

4 QUESTION & ANSWER

5 OPTIONS WORKSHOP All

6 SUMMARY. ANY FURTHER QUESTIONS?

Bath and North East Somerset – The place to live, work and visit

LEGISLATION

Flood and Water Management Act 2010 (FWMA)

The Act aims to improve the way we manage flood risk and

creates the new role of the Lead Local Flood Authority (LLFA)

ENVIRONMENT

AGENCY

LLFA

•Sea

•Main Rivers

•Reservoirs

•Ground water

•Surface Water

•Ordinary

Watercourses

Lead Local Flood Authority

Bath and North East Somerset – The place to live, work and visit

Lead Local Flood Authority

LOCAL PARTNERSHIP

The FWMA enables

partnership to be formed

between the LLFA and the

other relevant authorities.

Bath and North East Somerset – The place to live, work and visit

Strategic Flood Board

B&NES (various departments)

Environment Agency

Wessex Water

Lead Local Flood Authority

Operational Working Group

B&NES Council Highway

Maintenance and Drainage

Parish Council Rep.

Resident Rep.

Business

Public

Parish Council

Cluster Groups

B&NES Departments

Incl. Council Connect

(public)

Neighbouring Local

Authorities

Bristol Water

Avon Fire and Rescue

Canal and River Trust

Full Council

Bristol Avon River Trust

River Regeneration Trust

Planning, Transport & Environment

Management Scrutiny Panel

(Flood Risk Management)

Strategic Flood Board: Interactions

Bath and North East Somerset – The place to live, work and visit

Lead Local Flood Authority Briefing

Bath and North East Somerset – The place to live, work and visit

Objectives of the B&NES-Wide SWMP

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1. To produce a B&NES area wide SWMP

2. Consultation with appropriate parties

3. Awareness of respective management

responsibilities of partners and

stakeholders

4. Provide a picture of local flood risk that

will be easily accessible by all

5. Increased understanding of where flooding

will occur to inform spatial and emergency

planning

6. Increased understanding of the causes,

probability and consequences of surface

water flooding

Pulteney and Twerton

Name: Melvin Wood & Nigel Smith

Job title: Flood Risk Management

Date: 15th October 2014

Why are we involved?

We protect and improve the environment for people and the wildlife

Exercise a supervisory duty on all matters relating to flood defence

Implement coastal improvements and flood defence schemes

Permissive powers to regulate activities on ‘Main River’

Opportunity to work in partnership with B&NES and developers to secure long term solutions for Twerton and Pulteney.

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Pulteney Radial Gate The radial gate is part of the Bath FAS built in the 1970’s.

This asset is approaching the end of its design life

Impounds water at low flows in conjunction with Pulteney weir

In flood conditions it automatically opens as the head of water increases.

In a large flood event the radial gate has limited benefits.

The weir and concrete footings of the gate are owned by B&NES. We own and operate the metal element of the gate.

Large costs to maintain

Difficult structure to maintain due to limited access.

Health and safety issues of operating the structure and for the public.

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How a radial gate operates

Twerton Sluice Gates Twerton consists of a vertical and radial gate.

This asset is approaching the end of its design life

The concrete footings are owned by the EA and First Group. The gates are owned and operated by the EA.

Twerton’s primary function is to maintain water levels upstream in Bath. This is for navigation and amenity purposes as well as protecting foundations of structures in the World Heritage Area.

In flood conditions the gates are opened to allow water to continue downstream. This operation is automatic and rises to changes in river levels.

If the gates were to fail shut in a 1in 100 year flood this would increase the risk of flooding to 240 properties.

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20 O

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2014

TECHNICAL DIRECTOR ANDY WALLIS

RIVER AVON OPTIONS APPRAISAL TWERTON AND PULTENEY GATES

• Pulteney and Twerton sluice gates are important, but degrading, assets

• Need to be considering now what the long term solutions are

• Complicated sites so need careful thought

• Lots of potential for improvement

BACKGROUND TO STUDY

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Flood extents in 1 in 100 event with and without Twerton Gates open

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Now is the right time

• Can link into other regeneration sites

• Potential for partnership funding

OPPORTUNITIES

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• Linkage to other plans and strategies

• Amenity/visual/biodiversity

• Do Nothing

• Do Minimum

• Refurbish current sluice

• Like for like replacement

• Hydropower

OPTIONS – BOTH SLUICES 20 October 2014

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What have we missed?

OPTIONS - PULTENEY

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• Replace with fixed crest weir

• Replace with lock gates

• Infill the land

What have we missed?

• Replace one or both gates with fixed crest weir

• Replace one or both gates with variable crest weir

• Lower the retained water level

OPTIONS - TWERTON

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• So far talked about long term options only

• Opportunity to work with adjacent stakeholders at both sites to come up with combined solution that deliver all, or part of the final solution.

QUICK FIX OPTIONS

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Which is most important? What have we missed?

EVALUATION CRITERIA

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GBV

Flood Risk

Fisheries

Public Realm

Amenity

Heritage

Energy Generation

Navigation/Moorings

Safety

Education

Costs

WHAT IS IMPORTANT TO YOU?

Over to you!

• Time for Q&A then split into groups

• Anything we have missed?

• What is most important to you?

• What are your concerns?

• How would you evaluate success on this project?

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30-40 minutes in groups to discuss the different options and prioritise the importance of the different criteria.

Group facilitator to feedback at end.

FEEDBACK

Group facilitators to lead

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NEXT STEPS

Thank you!

•Report and matrix of options by Christmas

• Further consultation at end of this stage on preferred options

•Detailed appraisal of small number of options in early 2015

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Bath and North East Somerset – The place to live, work and visit

Question & Answer