Crindau Flood History the Dangers of Flooding Are Nothing New to the Community of Crindau
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Am I at risk of flooding? Crindau Flood History The dangers of flooding are nothing new to the community of Crindau. The low lying area has flooded a number of times in the past. Most notably in 1981 when 500 homes and businesses were affected, and more recently, extensive flooding was only very narrowly avoided! 1981 Flooding 2014 Flooding On December 13th 1981 a storm surge and high tides coincided to At 8:30am January 3rd 2014 tide levels reach 8mAOD at Newport cause extensive flooding of Crindau. Docks causing minor flooding of Crindau. The event was just inches • 500 homes and business flooded away from causing far more extensive flooding! • Average depth of flooding 300mm. Chest high in some areas. • Estimated to be a 1 in 10 year event • Tide level of 8.4mAOD recorded at Newport Docks • Evacuation warnings given to many homes • Sandbags deployed to prevent overtopping of low spots • 6 homes and businesses flooded • Alderney Street flooded to around 300-400mm Depth (m) <0.25 0.25 - 0.5 0.5 - 0.75 0.75 - 1 Present Day1 - 1.5 Flood Risk Future Flood Risk >1.5 331000 332000 The Crindau area is presently protected by a number of walls and Sea levels are increasing as a result of climate change. This will increase embankments, many of which are in a poor condition. the frequency and severity of flooding. The flooding that occurred in 1981 was approximately a 1 in 100 year Detailed flood modelling 190000 event. However190000 this may become an annual occurrence by 2114! carried out by Natural Resources Wales There may be over 1100 homes and businesses at flood risk in the estimates that Crindau Depth (m) <0.25 Crindau area by 2114 can expect to see 0.25 - 0.5 extensive flooding 0.5 - 0.75 The proposed flood defences for Crindau will be designed to account on average once in 0.75 - 1 for and adapt to climate change. every ten years. 1 - 1.5 >1.5 331000 332000 Predicted Sea Level Rise We predict that a 1 9.5 in 200 year event, 1 in 1 Year Tide 9.3 as show in the map 1 in 10 Year Tide to the right, would 9.1 1 in 200 Year Tide 190000 190000 flood 650 properties 8.9 and cause damages 8.7 of £45 million. 8.5 8.4mAOD - 1981 flood level 189000 189000 Annual average Level Water (mAOD) 8.3 8.1 damages are estimated 8mAOD - 2014 flood level at £1.3 million. 7.9 7.7 7.5 2000 2020 2040 2060 2080 2100 2120 Year Source: Esri, DigitalGlobe, GeoEye, i-cubed, USDA, USGS, AEX, Getmapping, Aerogrid, IGN, IGP, swisstopo, and the GIS User Community 331000 332000 189000 189000 Source: Esri, DigitalGlobe, GeoEye, i-cubed, USDA, USGS, AEX, Getmapping, Aerogrid, IGN, IGP, swisstopo, and the GIS User Community 331000 332000 What is the proposed solution? Scheme Overview The proposed Natural Resources Wales scheme will extend along the banks of the River Usk and Crindau Pill between the M4 motorway south down to the London to Cardiff railway line. The scheme will be made up of multiple components, including walls, embankments and ground raising. Following careful consideration of the feasibility, costs, benefits and impacts, the preferred option is to construct the new defences to provide protection against a 1 in 200 year event, including an allowance for effects of climate change over the next 50 years. The design will also be adaptive, so that it can more easily be ‘topped up’ in the future if required. What has informed our design? Environment Community Recreation Flood Risk • The River Usk is an important • Crindau is a built up area • Shaftesbury Park is an • There is a significant wildlife site and has a high level with limited space between important community facility tidal range of environmental protection riverbanks and properties used for sport, events • Tidal events are typically and general recreation • The Crindau Pill is home to • Some properties are well forecast protected reed beds and is immediately adjacent • There have been recent • Poor ground condition sometimes visited by otter to the riverbank improvements to the may force flood water children’s play area • Japanese Knotweed, • Residential properties under raised defences a non-native, invasive will be close to proposed • Busy footpaths and cycleways • High tides can cause surface species, is prevalent along construction works pass through the Park water systems to back up areas of Crindau Pill • Lyne Road Bridge is one • There is a well-used allotment • Climate change may of only two vehicle access along Pugsley Street • There are a lot of large, significantly increase flood risk routes into north Crindau mature trees (some protected) • There is an all-weather throughout Crindau • Awareness of flood basketball and football risk may be low area on Pugsley Street • Ground contamination has been found in many locations Wildflower planting Blue pennant stone T E E R T S 4 Y E L S G U P Pugsley Street wall materials and detailing 3 VP1 2 Theformer Sainsbury’s store is likely to be demolished and an embankment constructed across the site. The Pugsley Street garages will be demolished and several trees felled to create space to raise the ground level by 0.5 metres. A new stone faced flood defence wall will be constructed between Pugsley Street and the basketball court. New access stepswill beconstructed. New trees and shrubs will beplanted to provide colour and wildlife benefits. Constructionrequirewillwalltheboundaryremovalthe of of hedge and several trees, as well as changes to the existing entrancesto the allotments. An access ramp for vehicles and pedestrians will be built next to the basketball court. 1 2 3 4 WHEELER STREET T EE TR NS S A V E HOSKINS STREET T E E R T S View of basketball court from VP1 Y Scale: 1:1500 E L S VP1 G U P LEDBURY DRIVE 1 Legend Scheme Design T E E R T S Y N A B L A OAD LYNE R TREET ANY S ALB Scheme Design L YNE R O AD A new stone faced flood wall 1.5 metres high will be constructed 5 alongside the allotments. Railings will be mounted on top of the wall for security. Trees will be planted in a series of new planting areas created along Pugsley Street. New steps will be provided to enable pedestrian access into 6 the allotments. 7 A flood defence wall will be constructed around the children’s play area and will be buried for almost all of its length and will not be visible above ground. VP3 View of pavilion from VP3 14 VP3 15 13 12 11 Where the flood defence wall is visible, it will be clad in WHEEL 8 HO red brick to match the existing wall in the play area. LE Several trees will need to beSKINS S felled to enable the flood DBUR 9 defence wall to be constructed. The largest tree in the E play area, a London plane, will be protected. New flower R S beds will be created and new seating provided so that T Y DRIVE TREET park users can enjoy views of the River Usk. REE A new flood defence embankment approximately 1.5 10 10 metres high will be created between the play area and T the entrance to the Park off Lyne Road. The footpath and cyclepath will be placed on the top of the embankment. New access steps and a ramp will be constructed to enable 8 11 people to access the football pitches from the changing rooms. New grassed terraces may be created along the embankment next to the football pitches. Construction of the flood defence embankment will require 12 the demolition of the disused toilet block and changes to the garden of The Lodge. 7 EVANS STREET The embankment here will include a small section of VP2 13 wall, which will be finished with red brick to match the surrounding buildings and will include a timber fence placed on top for security. 6 The embankment continues between Shaftesbury Park 14 and Lyne Road, replacing an existing flood defence embankment that is in poor condition. Several trees will 9 need to be removed to enable the embankment to be built, but these will be replaced with new trees to create a picturesque avenue into the park. 15 Public access to the neighbouring streets will be 5 maintained by new footpaths onto the embankment. TREET S Y SLE PUG Terraced seating VP2 View along Pugsley Street from VP2 Wildflower planting TREET S Y SLE PUG Scheme Design VP5 VP5 Existing view of Lyne Road Bridge from VP5 View of Lyne Road Bridge from VP5 TREET ANY S ALB 20 18 19 L YNE R O VP5 AD VP4 View along Lyne Road from VP4 17 21 A new flood defence embankment will be constructed between 16 Lyne Road and Shaftesbury Park to replace the existing embankment, which is in poor condition. A new footpath and cyclepath will be created on the top of the embankment, with access provided into the adjacent streets. A new red brick flood defence wall will be constructed along 17 Lyne Road to the bridge over Crindau Pill. The wall will be 1.3 metres high. 16 New flood defence walls will be constructed alongside Crindau 18 Pill that connect together at Lyne Road bridge. The existing brick bridge parapet walls will be removed and replaced with VP4 new, slightly higher flood defence walls. All the walls in this area of the scheme will be finished in stone to match the Victorian bridge.