On this page you will find:
- Air and Water Overview
- Key Facts and Figures
- Sustaining the Landscape
- Management Influences and Forces for Change
- Policies and Priorities
Air and Water Overview
Air
Good air quality is important for a wide range of health benefits helping the most vulnerable in society such as children, the elderly and those with existing heart and lung conditions. Isle of Wight AONB is well known for its mild climate and clean air. Air is an important resource for the health of people and wildlife and its protection is essential. The good quality of the air means that the Isle of Wight has no Air Quality Action Plan (AQAP) however it has adopted a Mission Zero Climate and Environment Strategy (2021-2040)25 which seeks to address the climate emergency by impacting on levels of nitrogen dioxide, sulphur dioxide and particulate matter around vehicle and industrial emissions.
The prevailing south-west winds ensure the high quality of the air on the Isle of Wight. This feature of the landscape has attracted people to the Island for centuries most notably the Royal National Hospital for Diseases of the Chest, Ventnor, which was founded in 1868 and remained open for 80 years. It also allows a vast array of lichen and other species that are particularly sensitive to air quality to thrive on the Island, especially in areas that are sheltered from the prevailing weather.
Water
Water is essential for life, from wildlife through to farming, from industry and business to sustainable communities. The chalk geology of the Isle of Wight AONB is an aquifer collecting and storing rainwater. The Island’s rivers and streams are small and relatively impoverished in terms of biodiversity in comparison to those on the mainland; however, they are of landscape importance.
The Isle of Wight is an area of water scarcity and water locally is a precious resource. Abstraction rates and land use can have a major impact on the quality and quantity of water available as a physical resource. Some species and habitats are particularly sensitive to water levels and pollutants, with small changes having a marked impact on populations and quality of the ecosystems. This is also true for archaeological and palaeoenvironmental sites in wetlands.
The majority of watercourses on the Isle of Wight do not meet the ‘good’ criteria for ecological quality as measured under the Water Framework Directive. Of the ten water bodies wholly or partly in the IWAONB, nine are classified as ‘moderate’ and one poor (Wroxall Stream)74. This is due to a combination of historic modifications, leading to poor in-channel morphology and impediments to fish passage as well as nitrate, phosphate and uPBTs (global pollutants such as flame retardants and mercury) pollution due to domestic, industrial, commercial, and agricultural factors.
In Transitional Water Bodies (where fresh and salt water meet) around the coast of the Isle of Wight AONB, there are risks to the water quality from both land and marine-based activities. All major Isle of Wight watercourses enter European Protected Sites and two Heritage Coasts. Therefore, it is important to consider these designations when undertaking activities on land that may have a far-reaching influence on the marine environment. Furthermore, methods of coastline management can have impacts some distance away75.
In the light of anthropogenic climate change, increased incidents of dry, hot summers and warm, wet winters will require careful water resource management. This will be vital to the Isle of Wight AONB and the Island, as our island status exacerbates the finite nature of this resource. There is a need to make the Island more water self-sufficient and improve water resilience to ensure continuation of services for residents and businesses. To this end Southern Water are investigating the installation of a water recycling system at their Sandown site to recharge the eastern Yar with treated water.
The large proportion of semi-natural habitats across the Isle of Wight AONB help to reduce diffuse pollution and improves surface water and fluvial water quality. Moreover, the semi-natural habitats provide a valuable resource in managing the speed at which water moves though the landscape reducing flooding.
Key Facts and Figures
- 78 million litres of the Island’s water is abstracted for public water supply annually.
- Nearly 50% of ground water on the Island is over abstracted.
- The water stress classification for the Island is classified as “serious”.
- 47% of demand is supplied from groundwater, 23% from rivers and 30% from transfers from the mainland via a cross-Solent pipeline. All major groundwater extraction points are within the Isle of Wight AONB.
- It has been identified that 61% of nitrate pollution comes from agriculture and 32% sewage treatment discharges.
- 22 Sites of Special Scientific Interest (SSSI) (43 on the Island) are water dependent.
- There are 149km of river in the Isle of Wight AONB
- The Isle of Wight benefits from good bathing water beaches.
Source: Environment Agency and Southern Water
Sustaining the Landscape
Air
Air as a support service is of huge importance. The impact the AONB can have on air is limited as this is a global resource; however, localised impacts can have a local effect on air quality and therefore the species found within close proximity.
Air pollution has detrimental effects on the health of both people and ecosystems. With areas of good air quality there are lower instances of respiratory disease associated with environmental quality as well as an increase in the biodiversity. The Island is rich in species of lichen which are an indicator of clean air. e.g. Goldeneyes -Teloschistes chrysophthalmus.
Air provides a medium to disperse airborne pollution derived from the burning of heating or transport fuels or waste products of manufacturing. While the Isle of Wight does not suffer from poor air quality it is near the three major urban settlements of Bournemouth, Southampton and Portsmouth do periodically suffer poor air quality. Given the right environmental conditions it is possible pollution from these settlements could impact upon the Isle of Wight air quality; however, there is currently no available data to support this assertion.
Water
The water cycle is one of the keystones to the ecosystems on the Island making life possible. However, it is as a provisioning service that water is most associated. The Isle of Wight AONB chalk aquifer is one of the main resources for the Island’s water supply. Many of the rivers and streams suffer from low flows, which can be exacerbated by unsustainable levels of abstraction. Poor water quality is often worsened by diffuse pollution from agriculture, road run-off, misconnections and sewage treatment, as waterbodies remove a proportion of the Island’s sewage, industrial and farm waste and disperse it out to sea.
The total licensed water abstraction on the Isle of Wight is split between 23 per cent river water, 47 per cent groundwater and 30 per cent transfers from the mainland. The Eastern Yar provides the largest abstractions and the main aquifers on the Isle of Wight are the Chalk, the Upper Greensand and the Lower Greensand all found within Isle of Wight AONB76
Pollution (particularly phosphates), including sediment, and low flows are considered to be the major threats to the ecological quality of the freshwater habitats on the Island.
Sustainable management of this important resource is essential to the health of the Island’s environment. Southern Water are exploring new sources of supply because, with increased development in South Hampshire and impacts of climate change, there may be growing pressure on this supply from the river Test. Additionally, there is an energy cost associated with the pumping and balancing the water system network.
Parts of the Isle of Wight are subject to fluvial and tidal flooding. However, groundwater flooding is minimal. Flood events are typically localised but are having an increasing negative impact on houses and businesses. Records of historical flood events across the Isle of Wight AONB are limited. Two key rivers with flood risk problems which traverse the Isle of Wight AONB are: The Eastern Yar, suffering from rainfall runoff, blockages at structures, high winter groundwater levels causing high baseflows; and the Western Yar, where tidal locking at flood control structures cause the estuary to flood.
While waterbodies in the AONB are most known for their use as a resource or for their ecological importance, they are used for several recreational purposes including angling, sailing and boating.
The Heritage Coasts include coastal waters which are heavily used for recreation and navigation. Some beaches are popular destinations for a range of seaside sport and recreational activities.
Pollution is considered to be a major threat to the ecological quality of inshore waters. With much of the AONB’s coastline being designated as Special Protection Areas or Special Areas for Conservation, it is a requirement to keep these sites protected. Poor water quality in coastal and estuarine sites is as a result of sewage effluent, nitrogen run-off and storm water effluent, exacerbated by predicted climate change scenarios.
Management Influences and Forces for Change
Water Framework Directive
The Water Framework Directive (WFD)77,78 requires that all inland and coastal waters within defined River Basin Districts reach at least Good Status or Good Potential. It also defines how this should be achieved through the establishment of environmental objectives and ecological targets for surface waters. The WFD requires no deterioration in the current status of the water body. It also includes an objective to aim to improve any water body that is not presently at Good Status or Good Potential.
| Waterbody | Number | WFD Status 2014 | WFD Status 2025 | Status |
| Isle of Wight East TRAC | Good | Good | No change | |
| Newtown TRAC | Moderate | |||
| Western Yar TRAC | Moderate | |||
| Medina TRAC | Moderate | |||
| Caul Bourne | 6020 | Moderate | Moderate | No change |
| Brighstone Streams | 5940 | Moderate | Moderate | No change |
| Lukely Brook | 6250 | Moderate | Moderate | No change |
| Atherfield | 5920 | Moderate | Moderate | No change |
| Medina | 5990 | Moderate | Moderate | No change |
| Upper Eastern Yar | 6220 | Moderate | Moderate | No change |
| Lower Eastern Yar | 5971 | Moderate | Moderate | No change |
| Wroxall Stream | 6210 | Poor | Poor | No change |
| Blackbridge Brook | 6100 | Moderate | Moderate | No change |
| Monktonmead | 6120 | Poor | Moderate | Improved |
Source: Classification | River Basin Management Plan: maps (arcgis.com)
Urban development and engineering modifications may be the cause of these failures as much as factors found in the rural environment. The framework for delivering this directive is through River Basin Management Plans (RBMPs)79 and then through local Catchment Plans.76 The Isle of Wight is a catchment with a number of sub-catchments including the two Yar rivers and the Medina. A plan has been prepared and adopted by the Island Rivers Catchment Partnership to take initiatives and projects forward as resources allow.
Nitrate Vulnerable Zones
The Nitrate Pollution Prevention Regulations 200880 were introduced to implement the European Community’s Nitrates Directive, to reduce nitrogen losses from agriculture to water. They designate areas where nitrate pollution is a problem, known as Nitrate Vulnerable Zones. The Solent is considered to be an area particularly sensitive to nitrate pollution due to its effect on algal growth and the effect this has on feeding overwintering birds and other marine life. Priority transitional waters, which are failing their Water Framework Directive targets include eastern Yar, Wootton Creek, Medina and western Yar.
A mechanism to allow continued development in the Solent area has been devised by Natural England. Farmland can be taken out of agriculture (and therefore not received nutrient / nitrate inputs) to offset the nitrate inputs from new development. This nutrient neutrality has led to a cessation in nitrate inputs over 500 ha of land in the Isle of Wight AONB.
Catchment Sensitive Farming
The Isle of Wight Catchment Sensitive Farming (IWCSF) programme, co-ordinated by Natural Enterprise, provides advice to farmers and land managers on how to reduce diffuse water pollution from agriculture, across priority catchments. This partnership includes representatives from both the farming and water supply industries.
Southern Water Resources Management Plan 2024-207581
This draft document sets out a 5 year plan, and a longer term vision, for the provision of a reliable and healthy supply of drinking water. It will replace the current Plan (2020-70). The plan includes:
- Receiving water from neighbouring suppliers to increase water availability
- Introduce catchment schemes and take action to remove nitrates and protect against nitrates and pesticides
- Planning to prepare for the droughts of the future, which may be more severe than those we have experienced in the past.
Southern Water are looking at a water recycling project at their Sandown plant on the Isle of Wight whereby treated wastewater is pumped back upstream overland and released back into the river Yar at Alverstone. This will maintain river flows in times of low water levels whilst increasing the volume of water available for abstraction. Isle of Wight Water Recycling Project – Southern Water
Southern Water have developed an advisory service and grant scheme for their target areas on the island including the catchments of the eastern Yar and Medina (potable water sources).
Natural Flood Management
Increasingly nature-based solutions have been promoted for their importance in increasing the level of flood control though natural flood management. Measures include appropriate ditch management, use of woody debris, restoration of meanders and water retention structures such as ponds to slow down or keep back rainwater in the upper and middle catchment of rivers. The use of these methods can help alleviate flooding further downstream where urban settlements tend to have been established. DEFRA are looking to encourage more ‘low-tech’ solutions to flood management and encourage their adoption.
Invasive Non-Native Species
There are a few species which have been introduced into the Isle of Wight AONB which thrive on the watercourses and waterbodies causing a number of issues including increased bank erosion, shading of riparian habitats and competing with native vegetation. The number of species and abundance has increased rapidly over the past few decades organisations such as Natural Enterprise have sought to reduce the impact on the water environment by these species.
Policies for Air and Water
These policies should be read in conjunction with the overarching objectives for the Isle of Wight AONB as detailed on the welcome and overview page – Isle of Wight National Landscape: Area of Outstanding Natural Beauty Management Plan 2025-2030 – Isle of Wight National Landscape.
P22 Encourage catchment-sensitive land-use practices, promote the responsible use and conservation of water and responsible management of wastewater to safeguard the valuable water resource.
P23 Ensure AONB objectives are included in strategic approaches such as River Basin Management Plans and local Catchment Plans and support initiatives that deliver Water Framework Directive objectives.
Priorities for Delivery
- Support initiatives and approaches that improve the quality of our watercourses including advocate greater self-sufficiency for fresh water, reduce abstraction and increased opportunities for rainwater capture in larger developments and agriculture.
- Support initiatives and approaches that encourage greater landowner engagement on river and wetland management.
- Support initiatives and approaches that help to ensure good quality bathing water in AONB.