Resources

Introduction

5.1 Two of the core objectives of sustainable development are the effective protection of the environment and the prudent use of natural resources. The district contains a number of important environmental resources, including land, energy, water, wildlife, air and built heritage. It is important to distinguish between resources which are non-renewable and renewable:

1. Non-renewable resources are those which once damaged, destroyed or used up cannot be replaced, reused or recycled - these include energy from fossil fuels, like oil and gas, minerals such as sand and gravel, wildlife habitats and species, archaeology and historic buildings and the earth's atmosphere or air which is being continually damaged by pollution;

2. Renewable resources are those which occur naturally and repeatedly in the environment, such as energy from the sun, wind and oceans, and the fall of water. Previously developed land also, although limited in supply, can be seen as a renewable resource, which can be reused and redeveloped.

5.2 Prudent use of resources involves minimising the use of non-renewable resources and increasing the use of renewable resources, without endangering the resource or causing serious damage or pollution. This is necessary not only to preserve critical environmental assets, but also so that future generations will be able to enjoy such basic standards as clean water and air, heat and light and open space.

5.3 The planning system, in particular the development plan, has an important role to play in this, but it is one of a number of strands of legislation and action being taken by the government, local authorities and other agencies to ensure the prudent use of resources. Planning policies can help by controlling the location and design of new development so as to, for example, preserve wildlife areas and the landscape, protect water resources from depletion or pollution, increase the energy efficiency of new buildings and reduce the need to travel and use of the car (and hence reduce the use of fossil fuels and pollution). However, in doing this the Council must work in tandem with other agencies such as the Environment Agency, water companies, Health and Safety Executive, and English Nature, which have statutory responsibilities for these resources, as well as through its own environmental health services.

5.4 The Environment Agency, in particular, has a broader responsibility for the management of environmental resources, including water resources and quality, biodiversity, floodplains, air quality pollution controls and waste. The Local Environment Agency Plans (LEAPs) covering this district have been taken into account in preparing the policies in this chapter.

5.5 This chapter sets out the planning policies for the management of the district's resources. As well as its natural resources such as land, energy, water, wildlife and air, this also includes the district's built heritage, such as its Listed Buildings, Conservation Areas and archaeological remains, which are regarded as a non-renewable resource. The chapter also includes policies on noise and light pollution and waste management which together have an impact on the use of land.

Issues

5.6 Land is a finite resource and therefore has to be used wisely. It is the resource which the Plan has most control over, since it is the purpose of the planning system to ensure the efficient and effective use of land in the public interest. The district lies in an area of high development pressure, close to London, but has large tracts of countryside which require protection. At the same time, under government guidance the Plan must find land to meet the development needs of the district. A central objective of the Plan, therefore, is to recycle land and maximise the use of land which has already been developed or used.

5.7 Energy is a basic requirement of everyday life, to enable people to heat and light their homes, factories and businesses, run household appliances and fuel vehicles. Currently, the vast majority of our energy needs are met through the burning of fossil fuels, such as coal, gas or oil. However, this not only diminishes what are finite natural resources, it also produces gases, particularly carbon dioxide, which cause pollution and contribute to global warming. Government policy aims to reduce energy consumption, particularly of fossil fuels, and encourage greater use of renewable energy sources, such as solar power, as part of the strategy for sustainable development. Planning policies can contribute towards this through the location and design of development. This chapter includes relevant energy policies for the district.

5.8 Water is a crucial natural resource on which we rely for our drinking and other domestic needs, to support industry and for leisure and recreation. Watercourses and other wetland features are also integral features of the landscape, which support habitats for wildlife. It follows therefore, that water resources must be conserved and protected from pollution. The principal responsibility for the protection of water resources and quality lies with the Environment Agency and the provision of water supplies, drainage and sewerage treatment are the responsibility of the water companies. There is no separate government planning policy guidance on water. However, development clearly has a major impact on the supply and quality of water resources and, therefore, the Plan must ensure that account is taken of this resource in the location and design of development.

5.9 Wildlife and their habitats, such as grasslands, woodlands, heathlands and wetlands, are an integral part of the survival of human life, providing oxygen, water, clothing, health, education and recreation. The district contains a wide variety of wildlife habitats, including 5 Sites of Special Scientific Interest of recognised national importance and 190 Wildlife Sites of county importance, as well as other landscape features which are of local value in supporting or allowing the movement of wildlife. These are valuable natural resources, which the Structure Plan states should not be depleted. Development can have a damaging effect on these areas unless controlled and, therefore, this chapter contains policies to protect the sites of recognised value and protected species. Government policy, reflected in the Council's own Biodiversity Action Plan aims to increase biodiversity. Policies in this chapter seek to achieve this in relation to new development.

5.10 Clean air is a natural resource which is important to people's quality of life. Air pollution causes damage to health, but most significantly, greenhouse gas emissions cause climate change, with a threat to life at the global level. The main source of air pollution is transport, particularly cars, although some industrial processes are also responsible. Government policy recognises the important relationship between land use planning, transport and pollution control systems in tackling air quality. Policies aimed at reducing congestion and car usage will help to improve air quality; these are covered in the Movement chapter of the Plan. Powers to control major sources of air pollution rest with the Environment Agency and the Council has a duty to produce an air quality management strategy. These powers and duties must operate in conjunction with planning policies. The role of the Plan is to control the location and design of potentially polluting uses of land; the control of emissions is a matter for other agencies.

5.11 Welwyn Hatfield has a significant heritage of historic settlements, buildings and archaeological remains, which are culturally and educationally important to the district as a link with the past and form a finite and non-renewable resource. These range from the remains of Roman settlements, historic houses and villages dating back to medieval ages, to the more contemporary heritage of Welwyn Garden City. There are pressures for change and development within these areas and therefore it is important that the Plan seeks to preserve and where possible enhance these resources, to ensure that they can be enjoyed by future generations.

Strategy and Objectives

5.12 The overall aim of the Plan in terms of resources is to preserve and enhance the district's natural, cultural and built heritage and to minimise the use of natural resources. To achieve this there are a number of specific objectives:

1. To make the best use of land as a finite resource, by recycling and maximising the use of previously developed land and minimising the use of 'greenfield' land;

2. To minimise the use of non-renewable energy sources and maximise opportunities to use renewable energy in the design and location of new development;

3. To minimise the use of other non-renewable materials ;

4. To minimise the risks of flooding, ground and surface water pollution and encourage the conservation of water resources;

5. To protect the district's wildlife and its habitats and enhance biodiversity at every opportunity;

6. To minimise the risks of pollution in all its forms as a result of development and seek to raise air quality standards through enabling a reduction in car use and promoting tree planting;

7. To preserve and enhance the district's historic, architectural and archaeological heritage.

Policies

Land

Maximising the Use of Previously Developed Land

5.13 Land is a finite resource which in Welwyn Hatfield is under considerable pressure for development. Some 60% of the land within the district is countryside and designated as Green Belt, and is subject to policies restricting development set out in the Rural Areas section of this Plan. At the same time, the district must accommodate the future development needs of its population as well as ensuring open space is preserved. Government policy urges that development should be located on previously used land, before considering 'greenfield' sites. This is particularly so for housing development, where PPG3 requires a sequential approach to be taken in the selection of sites and states that by 2008, 60% of additional housing should be provided on previously developed land and through building conversions. The overall strategy of the Plan requires that development should be concentrated into the main towns and settlements and a number of development sites are identified in the policies of the Plan for Urban Areas as well as open space which should be protected.

5.14 Given the pressure on land within the district, the need to maintain open space and the thrust of government policy, it is important that best use is made of those sites which have been identified and of other land which has already been used or developed. In general the Council will not support proposals for the development of 'greenfield' land where suitable previously developed sites exist. In some cases there may be constraints preventing a site which has been previously used from being developed. For example, the site may be contaminated or require significant infrastructure. Where this is the case the Council will work with the site owners and other agencies to assist in bringing sites forward. There may also be existing or potential value of a site as a habitat for nature conservation, which may need to be taken into account.

Contaminated Land

5.15 Government policy in PPG23 Planning and Pollution Control specifically encourages the reuse of contaminated land as part of the strategy to make best use of land and relieve development pressure on 'greenfield' land. Under the 1995 Environment Act the Council now has a duty to inspect the district to identify sites which may be contaminated and determine the remediation requirements. The Council published its Contaminated Land Strategy in June 2001 which sets out the timetable for this. When considering planning applications for the development of land which may be contaminated, the Council will need to assess whether, in the light of the type of contamination, the proposed development will be suitable and whether there are likely to be any unacceptable risks to health or the environment arising from its development or future occupation. The responsibility for decontamination rests with the developer or owner. The Council will normally require developers to undertake a full investigation to establish the level of contamination in soils and/or groundwater/surface waters on such sites and undertake the necessary remediation measures, if necessary by imposing conditions on planning permissions.

Minerals

5.16 Hertfordshire, because of its underlying geology, is important for minerals such as sand, gravel, chalk and clay which are part of the national resource. There are a number of mineral workings within the district. As the minerals Planning Authority, Hertfordshire County Council is responsible for determining planning applications for the winning and working of minerals in the County. Policies regarding mineral extraction in the county are contained in the Minerals Local Plan, which was adopted in July 1998 and covers the period 1991-2006. The Minerals Local Plan identifies 'specific' sites and preferred areas to guide the location of mineral working in the County. This is currently being reviewed and potential locations for future sand and gravel workings identified. The policy towards safeguarding of mineral resources and mineral extraction is contained in the County Structure Plan.

Energy

5.17 The production, transfer and use of energy is a major contribution to greenhouse gas emissions and pollution. Schemes which help reduce the demand for energy through improving the efficiency with which energy is generated, transferred and used are key components of a sustainable development strategy. It not only offers environmental benefits but economic and social benefits (such as reducing fuel poverty). This section of the plan aims to provide the framework for more efficient forms of energy use as part of development. It should be noted that other guidance and legislation (in particular Building Regulations) have equally important roles to play, but are not repeated here. Further details and advice from the Council and other organisations is available.

Energy Efficiency

5.18 The demand for energy can be reduced through more efficient use, and the introduction of conservation measures in the design and layout of buildings. For example the use of Passive Solar Design (PSD) techniques can help to make the best use of shade or the sun's heat in order to offset the demand for cooling or heating. Factors which require consideration include orientation; built form and internal layout; window design; materials; reflective surfaces; atria and conservatories; and landscaping. Further details on PSD techniques can be found in the Supplementary Design Guidance note published in conjunction with this Plan Review. The Building Research Establishment's Environmental Assessment Method (BREEAM) also sets out principles for designing and constructing sustainable buildings, including energy matters.

5.19 Up to 70% of the energy of the fuel used in conventional power stations is lost as waste heat. Local small scale combined heat and power plants are more efficient because, amongst other things, they use the heat by-products to heat nearby housing or facilities. Developers of major schemes should consider the use of such plants. Although the Council's powers to influence some of the design and construction issues under the planning system are limited, it will seek to encourage good practice. Wherever possible consideration should be given to the incorporation of energy efficiency measures in all developments. Proposals for development should take into account the best practical environmental option. This can be defined as the option that provides the most benefit or the least damage to the environment as a whole, at acceptable cost, in the long term as well as the short term.

Renewable Energy

5.20 Government policy aims to reduce dependence on fossil fuels and encourage greater use of renewable energy sources where proposals are economically attractive and environmentally acceptable. Government planning policy is contained within PPS 22: Renewable Energy. There are several potential sources of renewable energy e.g. solar, waste, landfill gas, sewage and farm slurry, wind, water, geo-thermal and wood. In Hertfordshire, according to a 1997 survey by the Department of Trade and Industry, the potential for solar power generation is very significant and considerably higher than any other form of renewable energy. This type of energy is ideally suited to being generated at the local level, particularly for single dwellings, and thus new-build dwellings offer an excellent cost-effective opportunity to make a significant contribution to the harnessing of renewable energy in the district. Other sources of renewable energy can themselves raise environmental concerns such as pollution, traffic generation and visual impact. Whilst supporting the use of renewable energy in principle the Council will wish to take into consideration likely detrimental impacts. Applications will be required to be supported by an Environmental Impact Assessment where this is appropriate in terms of Circular 2/99.

Waste

5.21 The disposal of waste is an essential community service. The County Council is responsible for planning for all types of waste and the disposal of household and commercial waste, while the District Council is responsible for waste collection. The amount of waste produced is increasing, and the costs of disposal, both financially and environmentally, are rising. Waste is, therefore, an issue with important land use planning and environmental implications, which need to be considered as an integral part of sustainable development.

5.22 The Hertfordshire Waste Local Plan 1995-2005, adopted January 1999, should be referred to for waste management policies, and it sets out detailed background and guidance on waste planning matters. The Plan forms part of the Development Plan for Welwyn Hatfield District against which all planning applications are to be considered. The District Council recognises the limited direct involvement that it can have in waste disposal and other related development. These are matters for the County Council or, ultimately, are dependent on commercial activities and social responsibility outside the scope of planning. However, the Council is supportive of the strategy of the County Council as set out in the Waste Local Plan, which represents a major shift in policies away from a dependency on landfill as the main means of waste disposal. For example, a key component of the Waste Local Plan strategy is the incorporation of the hierarchy of waste management. The four elements of the waste hierarchy are:

• Minimisation;

• Re-use;

• Recovery - recycling, energy, composting;

• Disposal as a last resort.

5.23 Waste production and its implications need to be considered at all stages in the development process, from initial site clearance and the choice of building materials, through its occupation to its eventual clearance. The Council will seek to ensure that the design and organisation of works minimises the waste of materials, and that a minimum of materials are removed from the site. As much as possible of existing materials should be retained on site for re-use consistent with environmental practices. Material which is to be removed should be carefully segregated by type to enable reclamation and re-use elsewhere. On larger schemes materials recycling should take place on site and the products used in the development. Materials will have to be stored carefully so that they do not cause pollution or eyesores. Where sites are contaminated, on-site remediation is preferable where practicable and appropriate. This reduces the pollution potential and the problem is not merely moved elsewhere.

5.24 After re-using materials found on site, the practice most likely to aid waste reduction will be the use of recycled products. Recycled aggregates provide one example of such a product that is currently available. As awareness of the importance of conserving resources increases, the list of recycled products will extend. The design of all schemes should accommodate storage for a variety of different types of segregated waste. Communal schemes (e.g. mini recycling collection points) will be encouraged provided that problems of vehicular access, vandalism, potential pollution and noise can be overcome. The potential for the recycling of green waste for combined heat and power units within larger developments should be considered. Thought also needs to be given to the deconstruction of buildings and infrastructure, the practicalities, and ease with which materials may be recovered and re-used.

5.25 Whilst the Council will encourage all applicants to take notice of the waste implications of their schemes, only larger development schemes will be required to submit a demonstration of how waste management issues are to be addressed. Larger schemes are defined as:

• Developments of more than 5 houses;

• Commercial and industrial development of more than 235 sq.ms;

• Car parks with more than 200 spaces;

• Golf courses;

• Developments which attract large numbers of visitors; and

• Other developments which the Council considers to have important waste management implications.

Water

5.26 It is very important for sustainability to conserve water resources for the future and prevent pollution of surface and ground water. Although there have been few planning controls over water resources in the past, there are ways in which the planning process can influence the resource in dealing with development. In addition PPG25 Development and Flood Risk was published in July 2001 which states the importance that the Government attaches to the management and reduction of flood risk in the land use planning process.

River Corridors

5.27 The main rivers in the district are the Lee, the Mimram and the Mimshall Brook. Their corridors are important for water resources, encouraging biodiversity, fisheries and recreation and for their function as flood plains. They also make a significant contribution to the landscape. The Mimram is a high quality chalk stream and is considered to be of regional importance because of its diverse habitats and the Lee, which has been greatly modified in the past, provides a varied riverine landscape. The Mimshall Brook is a tributary of the Colne and flows west through North Mymms. The Brook is intermittent in parts as at Water End Swallow Holes. The Council will seek to promote through consultation with the Environment Agency and other relevant organisations the effective management of river corridors of the Lee, Mimram, and Mimshall Brook, the location of which are shown on the Proposals map, as important areas for water resources, biodiversity and recreation. There is a need to protect and, where possible, enhance the natural elements of the river corridors to maintain and increase biodiversity, their function as floodplains and to protect operational access. Development in river corridors should be set back from the river separated by a sympathetically landscaped buffer strip planted with suitable native species. The Council will support proposals which include the enhancement of the river corridor especially if it involves deculverting and/or naturalisation. This aim has to be balanced against improving public access and encouraging suitable water-related recreation.

Protection of the Water Environment

5.28 The water environment consists of the aquifer and surface water e.g. rivers, streams, wetlands and ponds. The aquifer in the district is essential to provide water supplies for domestic, industrial and agricultural use. Groundwater also feeds into the surface water system by means of springs and river flows. Pollution of ground and surface water can result from varied activities such as disposal of effluent in soakaways, contaminated land, landfilling of unsealed sites over permeable bedrock, chemical spillage from industrial process or discharge from roads. In turn this pollution can affect the natural water cycle and cleaning up of contaminated water, in particular groundwater, is very expensive and difficult. The Environment Agency has produced "Policy and Practice for the Protection of Groundwater " which provides a policy framework for the protection of groundwater, and is based on the principles of groundwater vulnerability. Source Protection Zone Maps are available from the Environment Agency. These show areas which form an increased risk to abstractions. The Council will therefore resist development following consultation with the Environment Agency that may prejudice both the aquifer and surface water quality. If proposals are acceptable the use of sustainable drainage systems, which amongst other objectives seek to reduce the concentration of pollutants entering the water environment, should be encouraged if they will lead to enhancement of ground water quality. The Environment Agency can offer advice on best management practices.

Development on Floodplains and Flood Prevention

5.29 Floodplains act as storage and conveyancing areas for floodwater and may also have high environmental and amenity value. Floodplains therefore need safeguarding from inappropriate development. Any development, including raising the floor of the floodplain, may affect its storage capacity. This results in an increased risk of flooding and may affect other parts of the interconnected water system. The Environment Agency has identified the floodplains in the district, the majority of which are in the Green Belt. The Council will resist proposals after consultation with the Environment Agency for new development in these areas.

5.30 New development outside floodplains can result in increased problems of flooding downstream because of an increase in run-off from impermeable surfaces. There may be ways however of ameliorating the problem by the use of sustainable drainage systems including, for example, balancing ponds, swales and porous pavements. These techniques will require appropriate design and siting. The suitability of certain infiltration techniques will also depend on site specific groundwater considerations. There may also be opportunities for increasing biodiversity with sustainable drainage techniques. The Council will not allow development, after consultation with the Environment Agency, that would increase the risk of flooding downstream because of increased surface run-off.

Conservation of Water Resources

5.31 Water companies still hold the responsibility for provision of water supplies and must provide water as a statutory duty, whatever the demand. However the supply of water, the conservation of water supplies, and wastewater disposal must be important factors in considering development. There is a need to ensure that measures to meet increased demand should not be detrimental to other water users of the environment. For example increase in demand impacts on local water tables and hydrology and may then have a negative effect on local wetland habitats and wildlife. The Mimram in particular already suffers from low flows and it is possible that the river has been badly affected by abstraction for public supplies. The Environment Agency is currently investigating the problem of low flows in the Mimram. Development should ideally be restricted to areas with an adequate existing water resource and a more sustainable approach applied i.e. the use of local water supplies, the recycling of drinking and wastewater. The Council will consult with the relevant bodies regarding proposals and would wish to promote sustainable water management where applicable, especially in larger development sites.

5.32 In addition all development should include water conservation measures. The Council accepts that some water conservation measures such as sustainable drainage systems, large water storage systems, reed beds and alternative water supplies can only be used on large scale developments, but other measures should be incorporated in small scale development proposals. These include:

• Water butts;

• Rainwater recovery systems;

• Soft planting;

• The use of permeable surfaces and minimal hard landscaping on areas such as driveways and patios to help reduce surface water run-off.

Biodiversity

5.33 Biodiversity is the term used to describe the variety of life throughout the natural world. The intricate and diverse networks of ecosystems provide the support systems which are essential for human existence i.e. oxygen, water, food, clothing, health and relaxation. Human activities however continue to destroy the world's biodiversity; over 100 species have been lost to the UK alone in the last century and many more are at risk including at a local level common birds such as the starling and house sparrow.

5.34 The Rio summit of 1992 made a commitment to maintain the world's biodiversity and the Government subscribes to the principles of the Rio convention. In consequence a UK Biodiversity Action Plan was published in 1994. This led to a County Biodiversity Action Plan (BAP), "A 50 year vision for the Wildlife and Natural Habitats of Hertfordshire", published in 1998. The BAP identifies key habitats and species in Hertfordshire. The Council has adopted a BAP for Welwyn Hatfield District to replace the Nature Conservation Strategy for the district.

Enhancing Biodiversity

5.35 PPG9 states that our natural wildlife heritage is not confined to the various designated sites but is found in many urban areas. In addition to protecting specific sites, the Council wishes to enhance biodiversity throughout the district by ensuring that all new development contributes positively to increasing the range of habitats and species in the area. In addition, the Council requires that new development should demonstrate how it would enhance a site's biodiversity, for example through a management agreement or the inclusion of appropriate landscaping. Applicants are expected to submit a sustainability statement covering ecological appraisal in accordance with Policy SD1.

5.36 PPG9 Nature Conservation identifies different levels of protection for sites of varying importance for biodiversity, for example European and National statutory sites such as Special Areas of Conservation (SAC), Special Protection Areas (SPAS), National Nature Reserves, Sites of Special Scientific Interest (SSSIs) and Local Nature Reserves and non statutory locally designated sites such as County Wildlife Sites. PPG 9 recognises that local and informal designations form part of a habitat network which helps to retain local biodiversity, but designation should only be for sites of substantive local value.

Sites of International Importance

5.37 The district contains a small part of the Wormley-Hoddesdon Park Woods candidate Special Area of Conservation (SAC), which is identified on the Proposals Map. This designation is intended to protect the habitat of threatened species of wildlife. In accordance with PPG 9 development proposals for a candidate SAC will be treated in the same way as if it had already been designated.

Sites of Special Scientific Interest

5.38 English Nature is responsible for the notification of Sites of Special Scientific Interest of national and international importance for nature conservation. These are areas of special national interest because of their flora, fauna, geological or landform features. There are five such sites designated within the district, which are identified on the Proposals Map. They are Sherrardspark Wood, SSSI 1; Wormley-Hoddesdon Park Wood South, SSSI 2 (also in Broxbourne and East Hertfordshire); Water End Swallow Holes, SSSI 3; Northaw Great Wood, SSSI 4; and Redwell Wood SSSI 5 (part Hertsmere). In addition the district shares a boundary with Tewinbury SSSI, which is in East Hertfordshire. The Council will protect these sites and any other SSSI designations, which may come forward in the future, from development proposals likely to affect them, following consultation with English Nature.

Local Nature Reserves

5.39 A Local Authority has statutory powers to set up and manage Local Nature Reserves on land in its ownership. Five Local Nature Reserves have been designated in the district, and are identified on the Proposals Map. They are Danesbury Park, LNR 1; Sherrardspark Wood, LNR 2; The Commons, LNR 3; Northaw Great Wood, LNR 4; and Mardley Heath, LNR 5. The Council would wish to protect these from development and also intends to identify and set up further sites in conjunction with English Nature and other interested parties, where appropriate and as resources allow.

Wildlife Sites

5.40 PPG 9 Nature Conservation also allows for the designation of Regionally Important Geological / Geomorphological Sites (RIGS). Such features of the landscape are of major importance for wildlife flora and fauna. They are similar to the Wildlife Sites in that they are non-statutory locally designated sites. The Hertfordshire RIGS group has identified a potential site in the district and there may be potential for further sites to be identified for example, through mineral workings.

5.41 The Hertfordshire Biological Records Centre (HBRC), in conjunction with the Herts and Middlesex Wildlife Trust, carried out a Habitat Survey from 1994 to 1997 and subsequently identified Wildlife Sites for this district, based upon the latest available information. These are listed in Appendix 1 and identified on the Proposals Map. Wildlife Sites are defined as areas, identified by locally developed criteria, which are the most important places for wildlife outside statutorily protected areas. The Wildlife Sites include most of the areas identified in the previously adopted Plan, additional sites and areas run by the Herts and Middlesex Wildlife Trust, Gobions Woodland Trust and the Digswell Lake Society. These Wildlife Sites may change over time and as new information becomes available sites may be added to or removed from the list in Appendix 1, depending on their value. Some Wildlife Sites extend into the settlements, but most urban areas as such, are not covered by the Wildlife Sites. Most areas of potential wildlife value within the urban areas are part of the network of 'Urban Open Land' sites designated under Policy OS1. Urban Wildlife Sites will be designated in the future when specific criteria have been developed in conjunction with the HBRC and the Herts and Middlesex Wildlife Trust.

5.42 The Council will seek to protect the Wildlife Sites from development and planning permission will not be granted for any development likely to cause harm to their wildlife habitats, unless there are strong reasons to do so and mitigating measures are taken. Within some sites, there may be a threat of harm from development which would normally enjoy 'permitted development rights', for example, war games, motorsports or clay pigeon shooting in woodlands or small scale buildings on those sites which are within the grounds of a residential property. Where this is the case and the Council considers that there is a real threat of 'permitted development' causing harm, it may consider the use of Article 4 Directions, to remove permitted development rights and bring such forms of development under planning control.

Protected Species

5.43 The loss of some species of wildlife has been increasing since the Second World War and therefore the Council will resist development which would adversely affect the most vulnerable species. Many endangered species may be found in many places not notified as SSSIs. These species are identified in the 1981 Wildlife and Countryside Act and in the Habitat Regulations, the Conservation (Natural Habitats) Regulations 1994. Where development is permitted that may affect those species the Council will where appropriate consider the use of conditions and/or planning obligations to:

• Facilitate the survival of individual members of the species;

• Reduce disturbance to a minimum;

• Provide adequate alternative habitats to sustain at least the current levels of population.

Trees, Woodlands and Hedgerows

5.44 Trees, woodlands and hedgerows are important for biodiversity and as a vital element in the landscape; they help reduce atmospheric pollution and the build up of CO2 and can reduce noise. They can supply shelter and help with a feeling of enclosure and greatly add to the character and attractiveness of the district, in both rural and urban areas. The district contains areas of ancient, semi-natural woodland as well as veteran trees, and hedgerows which can act as wildlife corridors between rural and urban areas. In the rural areas the changing nature of agriculture has resulted in the loss of woodland and more specifically hedgerows.

5.45 In the urban areas there is also a significant green heritage to protect. The origins of Welwyn Garden City, which combined the benefits of both town and countryside, set standards of landscaping which have been the basis of design for new towns ever since. This approach of planting of trees and shrubs combined with the retention of original trees, hedgerows and woods has continued throughout the urban areas of the district. The Council would wish to retain existing trees, hedgerows, and woodland whilst requiring where appropriate new planting of locally native species to encourage biodiversity. Trees covered by Tree Preservation Orders are protected by law requiring the Council's consent before potentially harmful work is carried out. Work to trees in Conservation Areas require six weeks notice to the Local Authority.

Air Quality

5.46 The maintenance of high air quality is a major factor affecting quality of life. Major developments, road related development, traffic levels and some types of industry can increase emissions which reduce air quality. The Environment Act 1995 places a duty on local authorities to review and assess air quality in their districts. Those areas that are expected to exceed national guidelines in the year 2005 will be deemed Air Quality Management Areas (AQMAs) and the local authority must devise a strategy to reduce pollution concentrations. The review is underway in Welwyn Hatfield District, but it is unlikely that any AQMAs will be identified. However, provision is made in the following policy to cover the possibility.

Noise and Vibration

5.47 Noise can have a detrimental effect on the environment and on quality of life. PPG 24 'Noise' provides guidance on the use of planning powers to minimise the adverse impact of noise. In accordance with that advice the Council will seek to ensure that noise-sensitive developments, such as housing, are separated from major sources of noise. It will also seek to ensure that new development with a potential for causing noise nuisance is sited away from noise-sensitive land uses, both existing and known proposed developments. Noise can be accompanied by vibration that can cause disturbance. British Standard 6472:1992 will be used to evaluate exposure to vibration in buildings. The Council has powers under Environmental Health legislation in respect of statutory noise nuisances.

5.48 In considering proposals for development the Council will take into account:

• Possible future increases in noise levels;

• That the introduction of noisy activities into some residential and rural areas can be especially disruptive because of their existing very low background noise levels;

• That intermittent sources of noise can be more disruptive than constant sources;

• That particular difficulties are posed by fast food restaurants, public houses, night clubs etc, both from noise generated within the establishments and by customers in the vicinity, traffic and parking, especially in view of their evening and late night activity;

• That whilst design measures such as orientation, layout and double-glazing can reduce noise levels within buildings, such measures are less effective in reducing the level of noise experienced in public or private amenity areas.

Light Pollution

5.49 Light pollution concerns the adverse effects of light spill from artificial light installations. Artificial light is beneficial for community safety and security, for extending the time available for recreation and leisure, ie optimising the use and viability of facilities such as sports playing surfaces and for adding interest (such as the enhancement of buildings). However artificial light can be detrimental to both humans and wildlife if poorly designed or installed. Street, security and commercial lights as well as sports floodlighting can illuminate wide areas of land and atmosphere. Residential amenity and both rural and urban views can be detrimentally affected. Artificial light can change the character of the countryside at night by creating the impression that it is urbanised, and thereby harm the character and openness of the Green Belt. Photos taken from satellites at night reveal the extent of light pollution in Western Europe and it is now virtually impossible for astronomers to find any location in southern England where light pollution does not disrupt visibility. Added together light spillage represents a massive waste of energy and also unnecessary expenditure.

5.50 The Council will use its development control powers to try to keep light pollution to a minimum. Careful lighting schemes and installations that avoid detrimental impacts on amenity and wildlife, and minimise spillage and glare will be encouraged. Where appropriate, the Council may require landscaping to minimise the effects of external lighting. In determining applications, the Council will use the guidance contained in the Institution of Lighting Engineers Guidance Notes for the Reduction of Light Pollution which also lists other relevant standards.

Telecommunications Installations and Apparatus

5.51 Government planning policy on telecommunications in PPG8 emphasises that modern telecommunications are an essential and beneficial element in the life of the local community and the development of the economy. They enable people to work, shop, gain access to information and services and be entertained without leaving their homes. In this way, modern telecommunications can also benefit the environment by reducing the need to travel and thereby reducing vehicle emissions. Telecommunications apparatus includes masts, aerials, radio antennae, satellite dishes and development for cable television.

5.52 PPG8 advises that local planning authorities should respond positively to proposals for telecommunications development, especially where alternative locations are unsuitable due to technical constraints, whilst at the same time, taking account of the need to protect the environment of urban and rural areas. This requires a balance to be struck between the wider benefits of telecommunications development and the potential harm it can cause to visual amenity.

5.53 It is essential to ensure that telecommunications development does not harm the quality and appearance of the natural and built environment, including the countryside, towns and villages in the district. The Council will therefore require telecommunications apparatus to be sensitively sited so as to minimise its visual impact. In all cases, opportunities to screen the development should be taken, such as by using existing tall buildings/structures or natural features such as trees or woodland. The Council will encourage mast sharing wherever this is possible and environmentally acceptable. When considering proposals for new free standing masts, the Council will require written evidence from the developer to demonstrate that they have explored the possibility of sharing existing masts or using locations such as tall buildings, together with evidence of why this is not practicable.

5.54 In recent years, there have been increasing concerns about the health implications of mobile telephones and their associated masts and base stations. In May 2000, the Independent Expert Group on Mobile Phones (IEGMP) chaired by Sir William Stewart, published their report (The Stewart Report) into the possible health effects of the use of mobile phones, base stations and transmitters. The report concluded that it is not yet possible to state categorically that there are no risks to health from the radiation that these installations produce and that further research is needed. It therefore recommended that a 'precautionary approach' should be taken in dealing with mobile phone technology. Accordingly, emissions should be required to fall within ICNIRP (International Commission on Non-Ionising Radiation Protection) guidelines and accord with the advice contained in PPG8 on locations next to sensitive sites such as colleges and schools, including nurseries or pre-school play groups. Due to the sensitivity of such sites, all applications and determinations received for mobile phone masts, base stations and transmitters proposed near college, school, nursery or pre-school playgroup locations will be required to include details of consultation in line with PPG8 or its successor.

5.55 The Council will work with the telecommunication code system operators in providing and maintaining a register of existing sites where planning permission has been granted for telecommunications development, in order to maximise the opportunities for mast sharing, and will encourage them to advise the Council of their wider strategic requirements for installations within the individual towns and settlements where they are proposing development. The Council will adopt the following policy in considering proposals for telecommunications installations and apparatus. Proposals may either require the submission of a planning application or an application for prior approval of details. Before installing certain telecommunications apparatus under permitted development rights, a code system operator must apply for a determination as to whether the Council's approval of the siting and appearance of the development is required. This only allows the Council to consider the issues of the siting and appearance of the development, not the principle of the development itself. This policy will be reviewed in the light of developing technology and further government guidance on the health issues associated with telecommunications development.

Historic Environment

5.56 The Historic Environment is by its nature irreplaceable. It is evidence of past human activity, from the prehistoric period to the present day. It encompasses the whole of the historic landscape not just designated sites, such as listed buildings, conservation areas, ancient monuments, archaeological areas of significance and registered parks and gardens, but also other historical features such as places of worship, defence installations, burial grounds, farms and fields, and sites of manufacture.

Conservation Areas

5.57 The district has eight Conservation Areas. These are the historic cores of Ayot Green, Ayot St. Lawrence, Essendon, Old Hatfield, Northaw, and Welwyn, together with two areas in Welwyn Garden City, the central part and the Beehive area. Their boundaries are defined on the Proposals Map. These areas contain significant links with the past, in terms of the historical development of the district and traditional forms of architecture. In particular, they contain most of the district's Listed Buildings. Therefore, it is important that the historical and architectural character of these areas is preserved and enhanced. As far as possible existing buildings should be retained and adapted for re-use rather than demolished and redeveloped. Where new buildings are acceptable, they must be designed to harmonise with their surroundings and preserve or enhance the character or appearance of the Conservation Area, using, where appropriate, traditional materials and features. Advertisements in Conservation Areas are dealt with in paragraphs 5.8 and 5.9 of the Supplementary Design Guidance. Shopfront security, shop awnings, canopies and blinds within the Conservation Areas are dealt with in paragraphs 6.5 and 6.11 of the Supplementary Design Guidance.

5.58 Within Conservation Areas the demolition of most buildings is subject to planning control. The general presumption in PPG15 Planning and the Historic Environment is in favour of retaining buildings which make a positive contribution to the character or appearance of a Conservation Area. The Council will therefore resist proposals for demolition within Conservation Areas, unless a very special case has been made and acceptable detailed plans for the site's redevelopment have been put forward. The wider effects of demolition and redevelopment on the character of the Area will be assessed before consent is granted. In order to aid the Council make this assessment developers will be required to provide documentary evidence in line with criterion (iv) of Policy R27.

5.59 Where appropriate, the Council will require historic materials and/or components arising from demolition or other works to historic buildings to be set aside either for re-use in alterations works to the building or for disposal to a bona fide architectural salvage company.

5.60 Local Authorities have a duty, under Section 69 of the Planning (Listed Buildings & Conservation Areas) Act 1990, to consider whether further reviews of their Conservation Areas are called for. As part of the monitoring process, and to assess the need for such reviews, the Council will endeavour to produce a character appraisal for each of the Conservation Areas in the district, as advised in PPG15. These character appraisals will identify those areas in need of review or enhancement, provide guidance for the design of new buildings and alterations to existing buildings and will also serve to co-ordinate the standard of development expected from the Council's own works, and those of statutory undertakers.

5.61 Unsympathetic alterations or improvements to buildings can damage the character of these areas as can neglect of infrastructure and landscape. Where, following a conservation area review or character appraisal, this is identified as a problem, the Council will carry out a dual policy approach of improvement works and Article 4 directions to remove permitted development rights, subject to the availability of resources.

Listed Buildings

5.62 Welwyn Hatfield District has over four hundred Listed Buildings, which are listed in Appendix 2. The preservation of the historic and architectural character of these buildings is of prime importance. Any alteration or extension must pay full attention to the existing fabric and to its restoration where decay or neglect has caused damage. The Council will consider the use of repairs notices and emergency repairs notices, where appropriate, to effect repairs to buildings not held in good repair or to barns under threat due to neglect. The Council will expect traditional methods and materials to be used, wherever possible, in any works carried out to a Listed Building. In considering proposals for development affecting a Listed Building, the Council will normally seek the advice of the Hertfordshire Building Preservation Trust. Listed Buildings often provide a refuge for protected species such as bats, barn owls etc. Their presence will be a material consideration in the determination of applications for Listed Building consent. Proposals for works to Listed Buildings should safeguard them from any adverse impacts resulting from the development and where appropriate enhance their habitat, in accordance with Policy R16 of the Plan.

5.63 In some cases it may prove impossible to maintain Listed Buildings in their original use. The most important issue is the preservation of their historic and architectural features and character. Therefore, the Council will adopt a flexible policy towards the use of Listed Buildings, since it is often the case that a more economic use can secure their restoration and ensure continued preservation.

5.64 There is a general presumption in favour of the preservation of Listed Buildings. It is important that these buildings are given maximum protection. Indeed there is a statutory duty on local planning authorities to 'have special regard to the desirability of preserving the building or its setting or any features of special architectural or historic interest which it possesses'. Demolition will be acceptable only in very exceptional circumstances. The Council will endeavour to protect Listed Buildings wherever possible, and will consider demolition only as a last resort. In assessing proposals for the demolition of Listed Buildings, the Council will consider the following factors, as advised in PPG15:

• The condition of the building, and the costs involved in repairing and maintaining it;

• The adequacy of efforts made to retain the building in use;

• The merits of alternative proposals for the site.

5.65 Where proposals for the demolition or major alteration of a Listed Building are submitted they should be accompanied by an impact assessment report setting out the historic/archaeological interest and importance of the structure affected by the proposal, and assessing the impact of the proposed demolition work. In cases where exceptional circumstances result in consent being granted for demolition or major alteration to a Listed Building, an appropriate condition will be imposed requiring the developer to secure a programme of archaeological historic building recording prior to the commencement of any works, including a photographic record. A full report of this recording work should be submitted to the Council for approval.

Historic Parks and Gardens

5.66 Historic parks and gardens contribute to the quality and character of the landscape, reflecting cultural and horticultural ideas of their time. They may often provide outstanding landscape settings for Listed Buildings, have rare plant collections and may be an immensely valuable ecological resource, contributing to biodiversity. The Register of Parks and Gardens of Special Historic Interest is prepared by English Heritage. The designation is non-statutory, but PPG15 "Planning and the Historic Environment" advises local planning authorities to protect registered parks and gardens in preparing development plans and in determining planning applications. PPG15 also allows for the identification of locally important historic parks and gardens that make a contribution to the heritage of the district. They also offer a resource for recreation, tourism and education and often provide outstanding settings for Listed Buildings.

5.67 The registered sites are identified on the Proposal Map. These are listed in Appendix 3 to the Plan, together with other sites which at present are regarded as being of more local significance. The Council will seek to preserve their character and setting through the application of its planning powers.

Archaeology

5.68 Ancient Monuments and archaeological remains are an important part of the district's heritage and form a finite and non-renewable resource which is important both culturally and educationally. These remains take the form of those that are known, such as scheduled ancient monuments, those that are anticipated, and those that are undiscovered and unsuspected. There are over 340 individual records of known archaeological sites and finds in Welwyn Hatfield recorded on the County Sites and Monuments Record maintained by Hertfordshire County Council. Of these, four are designated as scheduled ancient monuments under the Ancient Monuments and Archaeological Areas Act 1979 and are statutorily protected.

5.69 Government guidance, in the form of PPG16, explains the importance of archaeology and advises on the handling of such matters in the planning process. Particular emphasis is placed on the importance of policies within development plans and their implementation through development control, as a means of ensuring remains are preserved or recorded.

5.70 The list of Scheduled Ancient Monuments and Areas of Archaeological Significance is not exhaustive, and will be revised as necessary. Exclusion from either designation should not imply that a site has no archaeological merit. Some of the most important concentrations of archaeological remains recorded on the County Sites and Monuments Record, as maintained by Hertfordshire County Council, are identified on the Proposals Map as Areas of Archaeological Significance, although important archaeological remains may exist elsewhere in the district. These Areas have been identified in order to alert developers to the need to consider the archaeological implications of their proposals at the earliest possible stage of any development proposal in order to minimise potential conflict. However, the Council will seek to protect valuable remains throughout the district in its planning policies.

5.71 In considering planning applications on sites within the Areas of Archaeological Significance or other sites of potential interest, the Council will, as necessary, seek guidance from the County Council's Archaeologist. Account will also be taken of archaeological planning guidance notes where these have been produced by the County Council as supplementary guidance. Where appropriate the Council will seek to secure the enhanced management of sites and remains within the district.