Our Town Our River - The Story of the River Dargle Flood Defence Scheme bray.ie online exhibition

Our Town our River The story of the Dargle Flood Defence Scheme

www.bray.ie/town-river/

The Story of the River Dargle Defence Scheme This project was one of the key capital investment projects by Wicklow County Council and the Office of Public Works (OPW) with an investment of €46 million and in October 2017 saw the completion of this vital Flood Defence Scheme.

The scheme comprised a variety of flood defences, including construction of new sections of earth embankments, demolition and rebuilding of river walls with extensive stone facing, channel excavation, regrading and riverbank strengthening.

A range of landscape treatments in and adjacent to the river are to mitigate the impacts of the scheme on the local environment along the river corridor.

Along with the flood defences, there have been enhancement works that have transformed the local environment.

New and improved landscaping and walkways at the People’s Park, Ravenswell Road and the Lower Dargle Road.

The Boardwalk which complements and provides linkage between the People’s Park and the Fran O’Toole Bridge The flood defences aim to provide protection against a 1-in-100-year fluvial flood and 1-in-200-year tidal flood.

€46m investment

The History of the River Dargle Defence Scheme

The History of the River Dargle Defence Scheme

Key Timeline of the Development of the Scheme 1986

2006

01

2009

2013

2014

2015

2016

1986

Hurricane Charlie arrived over Ireland at the end of August 1986. The storm with high winds and heavy rain was one of the worst in living memory. The counties of Dublin and Wicklow were badly hit and there was extensive damage to homes and businesses with the River Dargle and the River Dodder both breaking their banks.

02

2006 to 2013

Scheme moved into development stage after approval from An Bord Pleanala followed by Compulsory purchase Order then in 2012 SIAC Construction were appointed as the Design and Build Contractor but this Contract was terminated.

03 Official Opening The River Dargle Flood Defence Scheme will be officially opened by Mr. Kevin “Boxer� Moran T.D., Minister of State at the Department of Public Expenditure and Reform with special responsibility for the Office of Public Works and Flood Relief on Wednesday 8th November 2017.

2014

Wicklow County Council appointed TKFM Ltd as Construction Management Services Provider (CMSP) for the overall scheme.

04

2017

The River Dargle Flood Defence Scheme was completed.

Flood Comparisons 1905 Flood - The river Dargle breaks its banks and floods Little Bray, one man is killed and hundreds are left homeless.

1986 Hurricane Charlie - More than a thousand people were evacuated from their homes in Bray after the river Dargle burst its banks, flooding over 500 houses to a height of seven feet during the storm. The heaviest rain fell in the Dublin and Wicklow mountains, with 280mm, or 11 inches, recorded on Kippure.

8 feet

Flood level heights recorded

6 feet

4 feet

2 feet

5 ft above ground level

5 ft 6 inches above ground level

1905

1986

Dargle Flood Defence Scheme Works By Section

Wallingford Model

Our Town our River The story of the Dargle Flood Defence Scheme

A large scale physical model of the River Dargle including its bridges, structures and Little Bray and other flood risk areas was constructed in HR Wallingford Laboratories in 2009.

The physical model was then tested under a wide range of different flood scenarios to verify the scheme design assumptions were correct for a 1 in 100 year fluvial event and a 1 in 200 tidal event.

Timeline of the Development of the Scheme July 2014 – Emergency Sheet Pilling Works commenced at La Vallee. These works were substantially complete in November 2014.

Ravenswell Road Flood Defence Scheme completed in December 2015 Maltings and Killarney Glen completed in April 2016.

Our Town our River The story of the Dargle Flood Defence Scheme

Works to Coburg Area were completed in 2015.

Works at Seapoint Court including reinstatement of the public footpath from Bray Bridge to Seapoint Court were completed in December 2015.

Slope Stabilization and landscaping to Right Bank of River at La Vallee completed in June 2016.

Debris traps opposite Riverdale Apartments completed in August 2016.

River Dredging completed in September 2016.

Foundation Strengthening works to the Dart Rail Bridge at Bray Harbour were completed in November 2016.

Upgrading of Lower Dargle Road completed in March 2017.

Board Walk and New People’s Park entrance opened to the public on Saturday May 20th 2017.

Stabilisation to right hand bank at Silverbridge completed in September 2017.

Ravenswell Road landscaping and amenity works completed in October 2017.

County Brook Flood Relief works will be completed in November 2017.

This work is additional to the original Flood Defence Scheme.

For the first time Little Bray and environs are protected from one in one hundred year flood event

Soil Stabilization and Scour Protection

Our Town our River The story of the Dargle Flood Defence Scheme

Hundreds of soil nails and acres of matting were installed in areas that were prone to landslides.

Thousands of tonnes of local stone were placed at the toe of each soil embankment to prevent erosion of the soil during a Flood

Silverbridge The river channel has been deepened and widened in this area.

A new retaining wall has been constructed to protect the N11 Dual Carriageway.

Our Town our River The story of the Dargle Flood Defence Scheme

Seapoint Court

Our Town our River The story of the Dargle Flood Defence Scheme

Ravenswell Road

Our Town our River The story of the Dargle Flood Defence Scheme

Ground floor levels in this area are 2m below the design flood level.

An emergency overflow outfall has been built on Ravenswell Road.

A sheet pile wall and earthen embankment were built to provide Protection in a flood event.

A linear Park has been constructed including key features such as Planting,

The old Right of Way from Seapoint Court to Fran O’Toole Bridge has been re-opened and a substantial new amenity area for the Public has been created

• A Viewing Platform over the river • Open Access to the river • A new Cycleway and Pathway as far as the Railway Underbridge • New public seating, planters and lighting

People’s Park

Our Town our River

Our Town our River

A new entrance to the Park has been built under the Scheme.

New Amenities for the Public

40 mature trees and 400m of new pathways have been constructed as part of the amenity works.

As well as providing protection to life and property in a 1:100 year flood event the following Public Amenities have been created for the benefit of the people of Bray.

The story of the Dargle Flood Defence Scheme

New park benches have been installed by Wicklow County Council.

The story of the Dargle Flood Defence Scheme

• Linear Park and Cycleway on Ravenswell Road • Public Seating and Walkway from Fran O’Toole Bridge to Seapoint Court • New Entrance and pathways and new benches in People’s Park, • New seating and picnic area near Rivervale Apartments • Boardwalk along Lower Dargle Road

Maltings & Fran O’Toole Bridge

Our Town our River

The river bed has been lowered by 1m. to cater for extreme floods.

A new 650m. wall has been constructed to protect the Maltings Estate from an extreme flood event.

The existing sewer network at Fran O’Toole Bridge has been realigned to remove obstruction to the riverflow.

A fourth arch has been added at Fran O’Toole Bridge in the form of a 14m wide by 70m long culvert under Castle Street. This will allow up to 300m³/sec to flow through in an extreme flood event.

The story of the Dargle Flood Defence Scheme

La Vallee

Our Town our River The story of the Dargle Flood Defence Scheme

In 2014 a new retaining wall 240 metres long was built at La Vallee and Riversdale to prevent further erosion of the river bank.

130 ground anchors were drilled to hold the new wall in place.

Extensive landscaping, planting and seating areas were installed for the Residents.

Irish Rail Dart Bridge

Our Town our River The story of the Dargle Flood Defence Scheme

To prevent erosion of the Bridge Piers and Abutments 15 metre long steel sheet piles, were driven into the soft ground and tied together with anchors and concrete.

The works were designed to allow continuous safe operation of the Dart Rail Services at all times.

A State of the art Real Time Movement Monitoring System was installed on the Rail Track, to provide a warning if movement of the rail tracks occurred during the works.

Glenwood and Killarney Glen The river channel was widened at Glenwood and Killarney Glen in order to provide the design flood capacity of 300mÂł/second.

A new wall 250m long was build and lined with Granite Masonry

Our Town our River The story of the Dargle Flood Defence Scheme

Coburg and River Lane Coburg and River Lane were badly flooded in 1986.

A new 300m long concrete wall faced with Granite and topped with bow top railings and an earthen embankment now protect the adjoining properties in these areas.

Our Town our River The story of the Dargle Flood Defence Scheme

Environmental Great care was taken to prevent pollutants from entering the river and to preserve the water quality.

Fish friendly features built into the scheme include fish passes at the Swan stream and the County Brook.

Low Flow Channels were built in the river at Rehill’s and the People’s Park, New nesting sites for Kingfishers, Sand Martens and Otters are part of the new environmental measures. Provided under the scheme.

Our Town our River The story of the Dargle Flood Defence Scheme

Boardwalk A 210m long Steel Board Walk runs along Lower Dargle Road allowing the public to connect to the River.

Our Town our River The story of the Dargle Flood Defence Scheme

Other Supporting Scheme Works Images

Online Newsletter

Through our online newsletter via our dedicated #OurTownOurRiver page on bray.ie visitors could get a real sense of the whole project and how the scheme was progressing. Why not visit www.bray.ie/town-river/ yourself.

New Boardwalk and Entrance to the People's Park

Superb new amenities open to the public

The Lower Dargle Road, the Boardwalk and the new entrance to the Peoples Park was opened to the public on March 15th 2017.

Dargle Flood Defence Scheme By Numbers 1,000 Concrete Truck Deliveries

Enough to fill 3 Olympic Swimming Pools

107,000 m3 of Soil Disposal

That’s 10,000 Truck Trips!

460 Tonnes of Steel

That’s the weight of one Boeing 747

Dargle Flood Defence Scheme By Numbers 45,500 tonne of Rock Protection

That’s the weight of 100 Space Stations

10km of Rock Anchors

That’s from Bray to Powerscourt Waterfall

2 acres of new Masonry Walls

That’s the size of the Aviva Stadium Pitch

Dargle Flood Defence Scheme By Numbers 18,000m2 of Piling

That almost covers 2 Croke Park Pitches

94 New Trees

That’s a small forest!

2 acres of new Public Paving

That’s twice the public area of Bray Main St

Dargle Flood Defence Scheme By Numbers 16 acres of Grassed Areas

That’s nearly the size of St Stephens Green

119 new Public Seats

That will nearly fill the Mermaid Arts Centre

Read more information about the scheme by accessing our dedicated #OurTownOurRiver page just visit http://www.bray.ie/town-river/

facebook.com/braytown

@bray_ie Hashtag #OurTownOurRiver

Bray Municipal District

01 2744900