Policy ENV9: Water Quality
Policy ENV9: Water Quality
The council will work in partnership to protect, manage and improve the water quality of the borough’s water environment particularly the quality of water bodies which are currently failing to meet the Water Framework Directive (WFD) requirements as set out in the associated River Basin Management Plan (RBMP) documents. In the interests of positively managing the water quality of the borough, new development should incorporate sustainable drainage systems .
The quality of the water environment is monitored as part of RBMPs and the Environment Agency’s monitoring process, the results of which will be reported through the council’s AMR. Should the monitoring indicate that there is likely to be a deterioration in an individual element’s band status of the borough’s water body(ies); Policy SPS7 will prevent further development which exacerbates such deterioration within the relevant catchment and intervention mechanisms will be required to improve the quality of the relevant catchment prior to the release of any further allocated sites or granting of planning permissions.
In order to protect and improve water quality, potentially contaminating development proposals on principal aquifers or within Source Protection Zones will need to demonstrate that groundwater and surface water is protected to prevent a deterioration of water quality and pollution of the water source.
Development proposals adjacent to a watercourse will incorporate measures to protect the watercourse in accordance with the Green Infrastructure Strategy and the actions of the River Basin Management Plans. Developments should include measures that will improve the water environment unless it is not viably or technically possible to do so.
Where new water supply or wastewater infrastructure is required or proposed in support of new development, the development will be phased alongside the provision of the infrastructure to ensure:
Where there is a capacity constraint the council will, where appropriate, apply grampian conditions to any approval to ensure that necessary infrastructure upgrades are delivered ahead of the occupation of the relevant phase of development.
|Basingstoke and Deane is located within a county that has more river and wetlands sites of national importance for wildlife than any other county in England. Given the importance of the borough’s water environment, the council will protect and enhance its quality and supports the River Basin Management Plan objectives for improving the status of the borough’s water bodies within the Thames and South Eastern Basins.
|The River Loddon is classified as a high quality chalk river, therefore requiring special protection for both water quality and ecology. The Loddon contains many important wetland and floodplain habitats which have been designated as Sites of Importance for Nature Conservation (SINCs) and in part is designated as a Site of Special Scientific Interest (SSSI). It is also subject to the European Union Freshwater Fish Directive, designated as an EU salmonid river that contains BAP habitat. The Test river valley is an SSSI and subject to an Environmentally Sensitive Area (ESA) scheme to maintain and enhance the landscape and protect archaeological and historical features.
|With two distinctive geological areas, the Thames Basin and Hampshire Downs, the north of the borough contrasts strongly with the south. The southern two thirds are dominated by chalk downland, a large proportion of which forms part of the Test and Itchen catchment. The northern part is influenced by deposits of clay and sand and is generally more impermeable, except for the chalk in the River Loddon at Basingstoke, and forms part of the River Thames catchment.
|The current urban extent of Basingstoke drains to the River Loddon catchment and ultimately into the Thames basin. Foul water from the town drains to these catchments via Basingstoke sewage treatment works which feeds into the upper reaches of the Loddon and smaller settlements to the north discharge via two smaller treatment works, which drain into the Bow Brook, a tributary of the Loddon.
|The majority of new growth is focused around the settlement of Basingstoke which drains to the Loddon. The River Basin Management Plan for the Thames basin identifies that the Loddon catchment is currently failing to meet the good ecological status of the Water Framework Directive (WFD). This is primarily due to treated effluent discharges into the River Loddon catchment from the Basingstoke area, and in particular, phosphate discharged from the Sewage Treatment Works. It is however important to recognise that WFD compliance is based on all elements that make the band status of a water body, including biological and physico-chemical. The modelling in the 2022 Water Cycle Study has shown that the impact of additional treated sewage effluent from the allocated sites around Basingstoke is unlikely to cause a deterioration of current physicochemical band status in the River Loddon catchment.
|River Basin Management Plans are documents that are produced by the Environment Agency and are updated on a six year cycle. These documents have been produced for, and set out the pressures facing, each river basin including actions to address these pressures and the baseline position for water bodies. The council is committed to supporting the objectives of the Water Framework Directive by working towards the delivery of the actions set out for this council in the relevant River Basin Management Plan(s) and Local Catchment Plans in partnership with the Environment Agency and other organisations.
|In respect of the Whitchurch and Overton sewage treatment works, these discharge to the chalk aquifer in the South East River Basin instead of directly into the River Test and therefore the potential impact of development sites on the groundwater quality is also of concern within the Test Catchment. The groundwater body status of the River Test is currently poor and therefore the impact of additional development will need to be managed. The Water Cycle Study has identified potential wastewater capacity issues at Ashford Hill, Oakley, Overton and Whitchurch during the Local Plan period that will require a new flow permit and potential upgrades. The council will work with the water companies and developers to ensure that the necessary infrastructure is in place to support development. Developers are encouraged to contact the water company as early as possible to discuss their development proposals and intended delivery programme to assess with identifying any potential water and wastewater network reinforcement requirements. As outlined in the policy, where there is a capacity constraint the council will, where appropriate, apply grampian conditions to any approval to ensure that any required infrastructure upgrades are delivered ahead of the occupation of the relevant phase of development.
|The use of sustainable drainage systems can also help improve water quality as any pollutants are reduced - including metals and hydrocarbons from roads and car parks. Water entering a local watercourse or groundwater body is cleaner as a result, and less harmful to wildlife habitats. The use of such systems is encouraged in Policy ENV9 and Policy ENV10 in the interests of improving water quality in the borough.
|The chalk aquifer (a principal aquifer) underlies much of the borough and is vulnerable to contamination. Of note are the groundwater bodies, known as the Basingstoke Chalk and River Test Chalk, which are currently failing to meet their WFD chemical status and are at risk from abstraction and/or poor nutrient management. The council, in consultation with the Environment Agency will need to be satisfied that the risks associated with development proposals within the principal aquifer or Groundwater Source Protection Zones has been evaluated and adequate protection measures put in place for sites that are at risk of contamination, given that contaminants could leach into the water source. The Environment Agency Source Protection Zones I, II and III are shown on the Policies Map.
|Proposals for development within the river corridors will be assessed against other relevant policies in the Plan, in particular Policy ENV5. Certain developments whose wastewater discharges into the River Test and Itchen catchment are also required to demonstrate nutrient neutrality as set out in Policy ENV4.
Implementation and Monitoring
The policy will be implemented through:
The policy will be monitored by: