Flooding Positive/Neutral Positive/Neutral Neutral Yes Yes 15
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Project Delivery Table: Summarised conclusions of the appraisal and assessment Appraisal and assessment conclusions Objective Within Beyond Urban Rural Outside the Borough the plan the plan period? period? 1. To ensure that the opportunity is provided for decent Strongly positive Neutral Neutral Yes Yes homes to be provided for all the community 2. To improve human health and wellbeing Positive/Strongly Positive Positive/Neutral Yes Yes positive 3. To reduce the gap between the most disadvantaged Positive/Strongly Positive/Neutral Positive/Neutral Yes Yes communities and the rest and to increase prosperity positive 4. To raise education levels and develop opportunities for Positive Positive Unknown Yes Yes everyone to find the skills needed to find, remain, and progress at work 5. To promote social inclusion and cohesion including Strongly positive Positive/Strongly Positive/Neutral Yes Yes creating a safe and secure environment positive 6. To encourage development and participation in Positive/Strongly Positive Neutral Yes Yes culture, sport, and the arts and enjoyment of the positive countryside 7. To sustain and improve vibrant rural communities Neutral Positive/Neutral Positive/Neutral Yes Yes 8. To maximise the use of previously developed land for Positive/Strongly Negative/Neutral Neutral Yes Yes development and to use land efficiently Positive 9. To improve the quality of land and reduce Strongly positive/ Negative/Neutral Neutral Yes Yes contamination Neutral 10. To improve the overall air quality of the Borough Negative Negative Negative Yes Yes 11. To improve water quality Positive Neutral Neutral Yes Yes 12. Will it maintain hydrology / coastal processes? Positive/Neutral Neutral Neutral Yes Yes 13. Will it reduce or minimise greenhouse gas emissions? Positive/Negative Negative Negative Yes Yes 14. To effectively manage the risk of flooding Positive/Neutral Positive/Neutral Neutral Yes Yes 15. To conserve and enhance biodiversity Positive/Negative Positive/Negative Neutral Yes Yes 16. To promote the use of sustainable forms of transport Positive/Negative Positive/Negative Negative/Neutral Yes Yes and reduce travel by car / lorry, where options are available 17. To protect, enhance, and make accessible the historic Positive/Strongly Positive/Strongly Neutral Yes Yes environment and assets, including landscapes (the positive positive quality and character), townscapes and settlement settings 18. To maintain and enhance geological and Neutral Neutral Neutral Neutral Neutral geomorphological sites 19. To ensure the sustainable use and management of Positive/Strongly Neutral Positive/Neutral Yes Yes natural resources positive 20. To reduce generation and disposal of waste, and Positive Neutral Positive/Neutral Yes Yes achieve sustainable management of waste 21. To enhance quality of, and access to, employment Positive/Strongly Positive/Strongly Positive/Neutral Yes Yes opportunities for everyone positive positive 22. To increase the economic performance of the Strongly positive Positive Positive Yes Yes Borough 23. To encourage investment in local services and facilities Positive Positive Positive/Neutral Yes Yes 24. To encourage sustainable design and practice Strongly positive Strongly positive Neutral Yes Yes 5 Context Flooding More than 50% of the Isle of Sheppey lies below high tide level and depends on substantial sea defences to manage flood risk. A sea defence strategy, developed for the Environment Agency in 1998, recommended measures to improve the defences. A scheme to protect the towns of Sheerness, Queenborough and Rushenden from tidal inundation from the north was implemented in 2001 (the Isle of Sheppey Northern Defences Project). In 2002, the Isle of Sheppey Western Defences Project was initially progressed, however, the project was put on hold in that year and restarted in May 2005. Early potential options for works to the western sea defences (illustrated to right) were developed and comprise: Option 1: Do nothing; Option 2: Maintain existing defences; Option 3: Improve defences along existing line to Kingsferry Bridge; Option 4: Improve defences along existing line to Kingsferry Bridge plus con- struct additional defence south of the trunk road (A249) and railway line; Option 5: Improve defences along existing line to Rushenden and construct new counterwalls inland. Maintain existing defences from Rush- enden to Kingsferry Bridge; and Option 6: As per option 5 except for ‘do nothing’ to existing defences from Rushenden to Kingsferry Bridge. A review of key environmental issues and opportunities associated with the options was undertaken together with a Condition Survey of the island’s existing Western and Southern sea defences and a 2D hydrodynamic modelling study to assess the extent of the flood risk under a range of scenarios. Condition Survey The Condition survey found the Western Defences to be generally of a good standard, but with some localised areas requiring repair. Their Standard of Protection is in excess of that recommended for urban areas (greater than a 1 in 200 likelihood in any year). This differs from the findings of the 1998 strategy, which stated that a lower Standard of Protection exists (1 in 20 likelihood in any year). The variation of the flood risk is primarily due to revised Still Water Level (SWL) data now available using latest research in this field. The revised data show levels that are lower than the levels used in the 1998 strategy for the same return period event (300mm lower for a 1 in 20 year event and 600mm lower for a 1 in 200 year event). Flood defences opposite the Caradon Queenborough Creek entrance Map of Options 4 & 5 site Flooding Flood Risk Modelling Study Queenborough Despite the generally good condition of the Western Defences on the Isle of Sheppey, failure of the island’s Southern defences could cause flooding to the urban areas of Sheerness, Queenborough and Rushenden. Therefore a detailed 2D hydrodynamic modelling assessment was undertaken. The revised Standard of Protection for the worst section of the southern defences is estimated to be 1 in 15 likelihood in any year. The modelling has demonstrated that floodwater from a 1 in 20 and a 1 in 50 year event causing a breach of the southern defences may reach the new A249 road, but would not overtop it. Flood water from a 1 in 100 year to 1 in 200 year event could overtop the A249, but this would not lead to flooding of residential property. The railway line, Sewage Treatment Works and south- eastern part of the industrial estate may still be at risk of flooding, but water would not penetrate as far as Rushenden and Queenborough. The figure to right illustrates this. Conclusions and Way Forward The flood risk to Sheerness, Rushenden and Queenborough is now considered significantly reduced compared with the information presented in the 1998 strategy. There is therefore no requirement in the near future for a major capital works scheme to the Western defences, although maintenance issues remain and will be addressed (Option 2 above). Whilst maintenance issues on the southern defences will be addressed, their long term future is being considered as part of a strategic approach to management in the whole Medway Estuary and Swale. An 1 in 200 Year Flood Extent & Depths estuary Shoreline Management Plan has recently commenced, which will set a high level policy framework for the area. This will lead to more Medway Estuary and Swale Shoreline detailed consideration of the implementation of Management Plan the policies via strategies and capital schemes where appropriate. In May 2007 a consultation draft of the Medway Estuary and Swale Shoreline Management Plan (SMP) was published. This document sets out a large scale assessment of the risks associated with coastal evolution and presents a policy framework to address these in a sustainable manner for the next 100 years. Within the context of this study SMP Policy Unit E 29 covers the area Rushenden to Sheerness. Here it is stated that the long term aim is to “Hold the Line: i.e. to maintain the existing defence line and protect the urban developments. It is acknowledged that habitats will be ‘squeezed’ in latter years however it is Queenborough all tide landing and flood anticipated that this will be balanced by habitat Queenborough Creek entrance flood defences growth in other parts of the estuary defences Context Planning Policy Context Strategic Planning Policy – The Kent and Medway Structure Plan The town of Queenborough and Rushenden has been identified as an area in need of positive Policy NK3 of the Kent and Medway Structure The Draft First Review of the Swale Borough action to achieve economic regeneration for Plan (2006) identifies Queenborough and Local Plan (2005), as Modified, in particular: many years. As indicated previously, the area Rushenden as a strategic development area • Policies AAP6, MU6, and MU7, in respect has suffered in the past from a relatively isolated with the objective of supporting economic of the regeneration of the Queenborough location and poor economic performance regeneration and diversification. It identifies the and Rushenden areas, in the context of a resulting from the decline of local industry. In area for mixed-use development for housing, Masterplan framework, which should include planning policy terms, the town also lies within employment and community facilities in a developer contributions strategy. the Thames Gateway growth area. conjunction with environmental improvements and transport measures, including