Hailsham South Wastewater Treatment Works - Installation of 7 no. Equipment Kiosks
Planning Statement
Planning Portal Reference: PP-07693479
September 2019
Hailsham South Wastewater Treatment Works - Installation of 7.no. Equipment Kiosks
Planning Statement including
Design and Access Issues
Planning Portal Reference: PP-07693479
September 2019
Issue and Revision Record
Revision Date Originator Checker Approver A 09/09/2019 Phil Jameson Clare Taylor John Nicklin
1 INTRODUCTION.
This document is in support of a planning application relating to the proposed upgrade of Southern Water's Hailsham South Wastewater Treatment Works (WTW), Station Road, Hailsham, East Sussex, BN27 2BY. Hailsham South WTW is a key Southern Water Services Limited (Southern Water) operational site that provides wastewater treatment services to a catchment population of approx. 30,162, located in the southern part of Hailsham, Polegate and the surrounding area.
As a sewerage undertaker, Southern Water is obliged to provide the appropriate facilities for the treatment of wastewater to the standard required by the Water Resources Act 1991 and the Urban Wastewater Treatment Regulations 1994. This scheme forms part of Southern Waters’ Asset Management Plan 6 (AMP 6) Programme.
The proposed works at Hailsham South WTW are part of a wider scheme focusing on improving effluent quality at five WTWs that discharge into the Pevensey Levels Site of Special Scientific Interest (SSSI). The other WTWs are Windmill Hill, Hooe, Rushlake Green and Hailsham North.
The proposed development is required to ensure Hailsham South WTW meets a new discharge consent for phosphorous as specified by the Environment Agency (which will come into effect in 2021) and therefore complies with obligations under the Habitats Directives and Water Framework Directive to improve the water quality of the Pevensey Levels. The upgrades to Hailsham South WTW are also required to ensure it has treatment capacity to cater for the anticipated catchment population growth to 37,935 by 2030.
Much of the proposed upgrade scope constitutes permitted development under Part 13, Class B (f) of the Town and Country Planning (General Permitted Development)
Order 2015, as: "any other development in, on, over or under operational land other than the provision of a building but including the extension or alteration of a building."
However, some of the proposed equipment kiosks cannot be categorised as ‘Permitted Development’ as they do not satisfy the above-mentioned criteria; They are considered to be buildings and therefore require planning permission.
2 SCREENING FOR ENVIRONMENTAL IMPACT ASSESSMENT.
The proposed works do not constitute Schedule 1 development under the Town and Country Planning (Environmental Impact Assessment) Regulations 2017 (EIA Regulations). The area of the proposed upgrade works i.e. those requiring planning permission plus those considered as Permitted Development covers approximately 2,800 square metres which exceeds the threshold of 1,000m square metres, where in accordance with Paragraph 11 (c) of Schedule 2 of the EIA Regulations screening for EIA should be carried out.
The potential environmental impacts of the proposed development are identified and assessed in this statement. An Ecological Impact Assessment has been carried out, which concludes through the mitigation measures outlined it is possible for the scheme to proceed without causing significant detrimental impacts on the ecological features present and has not highlighted any significant issues for designated sites, habitats or protected species. It is considered that the proposed habitat enhancements that will ensure an overall gain in biodiversity value.
The plant items and structures that comprise the proposed development are of a similar scale to much of the existing WTW plant and structures. The WTW boundaries are well screened by existing vegetation that will ensure that there is no adverse visual impact on the character of the surrounding area.
All works proposed are outside of Flood Zones 2 and 3 as defined on Environment Agency mapping. The proposed development will provide the infrastructure to enable compliance with the modified treatment permit.
The scheme is to be implemented in accordance with a Site Environmental Control Plan that will minimise the risk of any adverse construction related impacts. The overall number of vehicle movements associated with the construction phase will be relatively low and any highway impacts will be temporary in nature. Due to the nature of the new infrastructure and the proposed mitigation measures the proposed development will not generate any significant noise or odour and will not have an adverse impact on the amenity of the surrounding area.
This statement includes the necessary information in respect of selection criteria for screening Schedule 2 development, as set out in Schedule 3 to the EIA Regulations. It is not considered that the proposed development will have any significant effects on the environment by virtue of the its scale, limited increase in built form and given its nature, location and the existing use of the land. It is not therefore considered that the proposed development is EIA development.
3 THE APPLICATION SITE.
The proposed development is to be located on land within the existing Hailsham South WTW an operational site within the ownership of Southern Water Services Ltd. Hailsham South WTW is located to the south east of Hailsham The WTW site covers an area of approximately 6.2 hectares and is accessed via Station Road from the west.
The area immediately surrounding the WTW is mainly rural; The areas across Old Swan Lane to the north and immediately to the east of the WTW comprise open agricultural land. Open agricultural fields extend to the south and beyond Station Road
to the west. Residential caravan parks adjoin the eastern and western boundaries of the WTW. The smaller of the two parks is located to the north of the WTW access road from Station Road, whilst the larger park, known as Lion House Park is to the east of the site. The closet residential property to the WTW operational site boundary is located over 70m away to the west of the site. Whilst the closet residential property to the northeast is approximately 125m away from the WTW operational site boundary.
Swan Barn Business Centre and the Hailsham Household Waste Recycling Site are located across Old Swan Lane to the north-west of the WTW, whilst a new housing estate is under construction on land adjoining Old Swan Lane and Mill Road to the north east of the WTW.
The Pevensey Levels extend to the south east of the WTW and cover an area of approximately 3500 hectares. The Pevensey Levels is an area of English Marshland in East Sussex, between Bexhill in the east, Pevensey in the west and Hailsham in the north. The Levels are designated as an SSSI, Special Area of Conservation and RAMSAR Site.
The application site area, i.e. the area occupied by the proposed kiosks subject of this application, comprises approximately 290 square metres of the 6.2 hectares of the WTW site
The western part of the WTW site is occupied by buildings, tanks, plant and equipment used in the treatment processes. Treated final effluent from the WTW is discharged to the water course to the south of the WTW. Liquid sludge arising from the treatment processes is transported via tankers to Hailsham North WTW for dewatering, prior to transportation to Hastings WTW where it is used to generate renewable energy by anaerobic digestion.
There are three open settlement lagoons located on the eastern half of the site that provide the final stage of treatment for the effluent prior to discharge to the water
course. The area around the settlement lagoons is vegetated with an area of scrub and mature trees to the west of Lagoon 1. There are mature trees and hedgerows along the boundaries of the WTW that provide visual screening.
The majority of the proposed development will be located either on land between the open settlement lagoons and the settlement tanks or on land between the settlement tanks and the northern site boundary. The buildings requiring planning consent are located within these two locations apart from the MCC 8 Kiosk which will be located to the west of the settlement tanks but still over 100m away from the closest residential property.
The WTW site is not subject to any planning designations, as shown on the Wealden District Council Local Plan Proposals Map. Hailsham Waste Recycling Site which is allocated as an area for waste development within the East Sussex Waste and Minerals Sites Plan (2017). The site is located within Flood Zone 1 where the risk of flooding from rivers or the sea is very low.
The site is located within the administrative boundaries of Wealden District Council and East Sussex County Council.
Planning History.
No planning applications relating to the development of the site were found during a review of the East Sussex County Council On-line Planning Register
Pre-Application Advice
Southern Water submitted a request for pre application advice to East Sussex County Council (ESCC) for a slightly larger scheme on the site in December 2018. At that time the proposed development included a new sludge area, new Aeration Blowers a
Welfare Building and a temporary construction access from Old Swan Lane, none of which are included within this proposal.
Formal pre-application advice was received from East Sussex County Council on 20th February 2019 (see enclosed ref: PS/2018/1869). The response provided by ESCC concluded that the proposal can be supported in principle, subject to further information regarding the replacement planting and ecological enhancement of the site.
4 PROPOSED DEVELOPMENT.
The proposed development comprises an upgrade to the WTW including the provision of new plant and machinery, replacement and refurbishment of existing plant items, and the 7 no. equipment kiosks that require planning permission. The project scope items that comprise the proposed upgrade are listed in Table 1 below. The kiosks that require planning permission are:
- Low Voltage (LV) Switch Room Kiosk - Ferric Dosing Kiosk - Motor Control Centre (MCC) Kiosk (7) - Motor Control Centre (MCC) Kiosk (8) - Actisand Transfer Kiosk - Polyelectrolyte Dosing Kiosk - Washwater Booster Kiosk
The proposed upgrade works will result in changes to the current treatment processes at the WTW:
The introduction of tertiary treatment together with polymer dosing will enable treatment of wastewater to a higher standard. The function performed by the Lagoons, that is the last stages of the effluent
treatment processes will be undertaken by the new Actiflo Units, when they are operational all of the lagoons will no longer be operational. This will enable new discharge consent standards for phosphorous to be met.
As set out in Table 1 below, some elements of the project that are plant and machinery fall under Southern Water’s permitted development rights for operational land under Part 13, Class B (f) of the Town and Country Planning (General Permitted Development) Order 2015, as: “any other development in, on, over or under operational land other than provision of a building …”
Planning permission is required for ‘walk-in’ kiosks as they considered to be buildings, these items are highlighted in red in the table below.
Table 1: Project Scope Items: (for reference see also Proposed Site Layout, Drawing No: JN.639176.0Z0702-C):
Ref Plant Dimensions (m 3) Materials Planning no. Status 1 New Inlet Screens 6.5m (l), 6.3m (w), Stainless Steel Permitted 4.4m (h) Development 2 Screen Handling Units 7.8m (l), 6.0m (w), Stainless Steel Permitted 2.9m (h) Development 3 Standby Generator Within existing As existing Not (within existing building) building Development 4 Low Voltage (LV) Switch 9.1m (l), 5.5m (w), Glass Planning Room Kiosk 3.4m (h) Reinforced Permission Plastic Required 5 Replace Inlet As existing - below As existing Permitted Submersible Pumps ground Development 6 New RAS Submersible As existing - below As existing Permitted Pump ground Development
7 Replace Existing Aeration Pipework within As existing Permitted System with 8 no. bridge Aeration Ditches Development aerators (4 per ditch) 8 New Weirs to Final Within existing As existing Permitted Settlement Tanks Final Settlement Development Tanks 9 Replace RAS Flowmeter As existing As existing Permitted Development 10 4 no. New Actiflo Units Each 13.1m (l), Steel Permitted 3.7m (w), 5.0m (h) Development 11 Motor Control Centre (7) 11.8m (l), Glass Planning Kiosk 5.8m (w), Reinforced Permission 4.25m (h) Plastic Required 12 New Final Effluent Below Ground and Concrete Permitted Chamber with Phosphate Above Ground Chamber Development and Iron Monitoring Kiosk Kiosk less than Glass 29m 3 Reinforced Plastic Kiosk 13 New Security Fence Total height 2.4m Chain-link with Permitted wire mesh fence 3-strand barbed Development topped with barbed wire (as existing wire boundary fence) 14a Actisand Transfer Kiosk 6.8m (l), 5.8m (w), Glass Planning 4.25m (h) Reinforced Permission Plastic Required 14b Polyelectrolyte Dosing 6.8m (l), 5.8m (w), Glass Planning Kiosk 4.25m (h) Reinforced Permission Plastic Required 15 New Sand Silo 2.9m diameter, Steel Permitted 8.4m (h) Development 16 Extension to Internal Ground Level Concrete Permitted Access Road Development 17 Tertiary Treatment Below Ground Concrete Permitted Pumping Station Development
18 Motor Control Centre (8) 8.0m (l), Glass Planning Kiosk 5.8m (w), 4.05 (h) Reinforced Permission Plastic Required 19 Ferric Dosing Kiosk 11.0m (l), 4.1m (w), Glass Planning 3.6m (h) Reinforced Permission Plastic Required 20 Temporary Construction Ground level Constructed Permitted Road from compacted Development crushed rock 21 Washwater Booster Kiosk 5.5m (l), 4.0m (w), Glass Planning 2.5m (h) Reinforced Permission Plastic Required
Development Requiring Planning Permission.
LV Switch Room Kiosk (Scope Item No. 4, Drawing No. JN.639176.0Z0708-B).
The proposed LV Switch Room Kiosk will be rectangular in shape and constructed from GRP coloured dark green. As set out in Table 1 the kiosk will be 9.1m in length, 5.5m in width and 3.4m in height, with access doors in its north and south elevations. The kiosk is to be located in the centre of the site, north of the Final Settlement Tanks and will contain the electrical switch-gear equipment associated with the power supply to the WTW.
Ferric Dosing Kiosk (Scope Item No. 19, Drawing No. JN.639176.0Z0703-B).
The proposed Ferric Dosing Kiosk will be rectangular in shape and constructed from GRP coloured dark green. As set out in Table 1 the kiosk will be 11.0m in length, 4.1m in width and 3.6m in height, with external staircases to access doors in the south and east elevations with an additional access door on the west elevation. The kiosk will contain dosing equipment that is necessary to remove phosphorous from the effluent and enable compliance with the new effluent discharge consent. The kiosk is to be
located in the centre of the WTW site and will be accessed by the proposed road (scope item No.16) There will be an emergency shower and a bunded chemical delivery area located in close proximity.
Motor Control Centre (7) Kiosk (Scope Item No. 11, Drawing No. JN.639176.0Z0713- A).
The proposed Motor Control Centre (7) Kiosk will be rectangular in shape and constructed from GRP coloured dark green. As set out in Table 1 the kiosk will be 11.8m in length, 5.8m in width and 4.25m in height, with access doors in the west elevation. The kiosk is to be located to the east of the WTW site, in proximity to the new Actiflo Units. The MCC kiosk will contain electrical switch-gear equipment necessary to operate the tertiary treatment plant.
Actisand Transfer Kiosk (Scope Item No. 14a, Drawing No. JN.639176.0Z0704-B).
The proposed Actisand Transfer Kiosk will be rectangular in shape and constructed from GRP coloured dark green. As set out in Table 1 the kiosk will be 6.8m in length, 5.8m in width and 4.25m in height, with access doors in the south elevation. The kiosk is to be located to the south of the WTW site, immediately adjoining the new sand silo (scope item No. 15) to the west and the Polymer Dosing Kiosk to the east. The Actisand Transfer Kiosk will contain the micro-sand delivery system to the tertiary treatment plant.
Polyelectrolyte Dosing Kiosk (Scope Item No. 14b, Drawing No. JN.639176.0Z0704- B).
The proposed Polyelectrolyte (Polymer) Dosing Kiosk will be rectangular in shape and constructed from GRP coloured dark green. As set out in Table 1 the kiosk will be 6.8m in length, 5.8m in width and 4.25m in height, with access doors in the south elevation. The kiosk is to be located to the south of the WTW site, immediately adjoining the
Actisand Transfer Kiosk. The Polymer Dosing Kiosk will be used for storage and will contain the polymer dosing equipment for tertiary treatment plant.
Motor Control Centre (8) Kiosk (Scope Item No.18, Drawing No. JN.639176.0Z0705- B)
The proposed Motor Control Centre (8) Kiosk will be rectangular in shape and constructed from GRP coloured dark green. As set out in Table 1 the kiosk will be 8.0m in length, 5.8m in width and 4.0m in height, with access doors in the south elevation. The kiosk is to be located towards the west of the WTW site. The MCC kiosk will contain electrical switch-gear equipment to operate the aeration plant.
Washwater Booster Kiosk (Scope Item No 21. Drawing No. JN.639176.0Z0714-A)
The proposed Washwater Booster Kiosk will be rectangular in shape and constructed from GRP coloured dark green. As set out in Table 1 the kiosk will be 5.5m in length, 4m in width and 2.5m in height, with access doors on its northern elevation. The kiosk will be located towards the south of the WTW site.
Construction Compound.
Temporary construction compounds will be required for the duration of the works. The temporary compounds will be located within the operational area of the WTW, as shown on the Site Layout Plan, Drawing No. JN.639176.0Z0702-C.
The temporary compounds constitute permitted development under Part 4, Class A of the Town and Country Planning (General Permitted Development) Order 2015, as:
“The provision on land of buildings, moveable structures, works, plant or machinery required temporarily in connection with and for the duration of operations being or to be carried out on, in, under or over that land or on land adjoining that land.”
5 PLANNING POLICY
National Planning Policy.
The revised National Planning Policy Framework (NPPF) was published on 24th July 2018. The policy guidance it contains which is relevant to the determination of this application includes provision for:
A presumption in favour of sustainable development. Approving development proposals that accord with the development plan without delay. Proactive drive and support for sustainable economic development to deliver infrastructure that the country needs.
The Development Plan.
The Development Plan for the proposed development comprises the adopted Wealden District (Incorporating Part of the South Downs National Park) Core Strategy Local Plan (adopted February 2013); the Saved Policies of the adopted Wealden Local Plan 1998, and; the East Sussex, South Downs and Brighton & Hove Waste and Minerals Local Plan, February 2013.
The development plan policies that are considered to be relevant to the assessment of the proposals are:
Wealden District (Incorporating Part of the South Downs National Park) Core Strategy Local Plan :
- WCS7: Effective Provision of Infrastructure. - WCS12: Biodiversity. - WCS14: Presumption in Favour of Sustainable Development.
Wealden Local Plan 1998 - Saved Policies:
- EN5: Water Resources. - EN12: Protection of Trees and Woodlands. - TR3: Traffic Impact of New Development.
East Sussex, South Downs and Brighton & Hove Waste and Minerals Local Plan, February 2013:
- WMP1: Presumption in Favour of Sustainable Development. - WMP3: Minimising and Managing Waste during Construction - WMP10: Management of Waste Water and Sewage Sludge. - WMP22: Increased Operational Capacity within the Site Boundary of Existing Waste Facilities. - WMP25: General Amenity. - WMP26: Traffic Impacts. - WMP27: Environment and Environmental Enhancement. - WMP28b: Water Resources and Water Quality.
5 PLANNING ASSESSMENT
Principle of Development / Wastewater Infrastructure.
The policies of the development plan are supportive to the provision of necessary wastewater treatment and utilities infrastructure. Policy WCS7 is aimed at ensuring the adequate provision of infrastructure, including utility services, to support new and existing development.
Policy WMP1 advises that waste development that accords with the Waste and Minerals Local Plan will be approved without delay unless material considerations
indicate otherwise. Policy WMP10 advises that proposals for the provision of new wastewater treatment facilities will be supported where the development is a necessary extension to or replacement of existing infrastructure and where the development is required to:
Meet the relevant environmental standards. Improve the operational efficiency of wastewater and sewage sludge management. Enable planned development to be taken forward.
Policy WMP22 sets out that proposals for increased operational capacity within the boundary of existing waste management facilities will be supported in principle where the development is required to meet environmental standards, or to improve the operational efficiency of the facility.
The proposed upgrade to Hailsham South WTW is necessary to ensure ongoing compliance with obligations under the Habitats and Water Framework Directives (to improve water quality in the Pevensey Levels). The scheme is also required to ensure compliance with a new effluent discharge consents for phosphorous. In addition, the proposed upgrade is also required improve the operational efficiency of the WTW to meet the needs of the growing population in the Hailsham area up to 2030 i.e. as detailed in Policy WMP10; to Enable planned development to be taken forward.
The proposed development will be located entirely within the boundary of the Hailsham WTW site. As it is required to meet environmental standards and improve the operational efficiency of the WTW thus enabling accommodating the wastewater needs of the planned population growth. The principle of the proposed development is considered to comply with Development Plan Policies WCS7, WMP1, WMP10 and WMP22.
Ecology & Biodiversity.
Policies WCS12 and WMP27 seek to prevent a net loss of biodiversity and maximise opportunities for biodiversity and habitat creation. Saved Policy EN12 advises that the Council will seek to retain and enhance the contribution of trees and woodland areas to the landscape character of the District.
An Ecological Impact Assessment has been carried out and is enclosed with the planning application. The Assessment concludes the Scheme will result in the permanent loss of 0.16ha of scrub, semi-improved grassland and tall ruderal vegetation between then inlet works and the lagoons i.e. the scheme impacts on vegetation that has the potential to provide habitat for, breeding birds including Cetti’s warbler, reptiles, Great Crested Newts (GCN), bats, and badgers.
In accordance with Policy WMP27, it is proposed to implement a habitat enhancement scheme as shown on the enclosed Landscape General Arrangement Plan, Drawing No. PJC.0802.001 Rev A and Landscape Detailed Planting Plan, Drawing No. PJC- 0802-002 Rev A. The proposed habitat enhancements will permit the scheme to proceed without causing significant detrimental impacts on the ecological features
- Backfilling part of the western end of Lagoon 1 and planting with native mixed woodland species. Native wildflower swathe will be created through the woodland planting area. - The backfilled area will have a sloping gravel margin with a marginal planting swathe. - Floating islands with marginal planting will be created in Lagoons 2 and 3.
The proposed enhancement scheme will provide continued habitat availability for GCN, reptiles, bats and other species throughout and after works. These enhancements would represent biodiversity net gain through the introduction of higher quality habitat than that which will be lost.
Re using, where possible, the excavated spoil created during the upgrade works to create these features complies with the aspirations of Policy WMP3d which seeks to: “… minimise the waste arising from construction, demolition and excavation works in order to maximise the sustainable management of waste and in particular, to minimise the need for landfill capacity”. The proposed development is therefore considered to be in accordance with EN12, WCS12 and WMP27.
Amenity.
Policy WMP 25 seeks to ensure all aspect of amenity are considered in order to protect the standard of amenity appropriate to the land uses of the community likely to be affected by the development.
Visual amenity
The proposed development will be located towards the centre of the WTW site between the lagoons and operational plant area, that is over 100m away from the closest residential receptor. As the WTW site is well screened from public viewpoints by existing mature trees and hedgerow along its site boundaries the proposed kiosks will not have a detrimental impact upon the visual amenity of the area including viewpoints along nearby public rights of way and highways. It is suggested the additional landscaping and habitat creation proposed as part of the development will have a positive impact upon the landscape character of the area.
Air Quality & Odour
The kiosks will not impact on air quality and will not generate any significant noise, vibration or dust. They will not cause any additional odour emissions.
An Odour Assessment has been prepared in respect of the WTW upgrade and is submitted with the planning application. The assessment was undertaken to determine if off-site odour impacts are likely to change as a result of the proposed works upgrade. The results of the qualitative risk assessment concluded the proposed change in the process treatment including the replacement of the lagoons with an actiflo tertiary treatment process will result in a 9% decrease in the risk of off-site odour impacts, as the tertiary treatment actiflo plant presents a lower odour risk than the existing open to atmosphere lagoons, which will be decommissioned as part of the upgrade works. It should also be noted that the results of the Odour Assessment do not take account of any odour reductions that will result from the refurbishment of existing assets, accordingly a 9% decrease is a conservative estimate.
Noise
Since pre-application was undertaken with East Sussex County Council, the WTW upgrade project scope has been revised and it is no longer proposed to install new Aeration Blowers. The new plant and equipment that is part of the project scope will not generate any additional operational noise that that current experienced at the WTW
The development is to be implemented in accordance with the enclosed Site Environmental Control Plan (SECP). The SECP will address the environmental issues associated with the construction works and will identify any mitigation measures proposed. The purpose of the SECP is to reduce the risk of adverse impact of construction on sensitive environmental receptors, including human health, and to minimise disturbance to the surrounding area.
It is not considered that the proposed development will have any significant impact on the amenity of the surrounding area and for that reason is in accordance with Policy WMP25.
Transport / Traffic.
Policy WMP26 sets out that proposals will be permitted where the highway network is capable of accommodating the volume and nature of traffic generated by the proposal without detriment to highway safety. For this proposal the major traffic impacts will be associated with the construction phase of the development.
Construction Traffic.
It is anticipated the proposed development will have a 75-week construction period which will generate on average 8 HGV movements (4 no. vehicles) and 20 light vehicle/car (10 no. vehicles) movements per day during the peak construction period. However, outside the peak construction period vehicle numbers will be considerably less.
All vehicles will use the existing WTW access from Station Road to access the site. Deliveries to site will seek to avoid the morning and afternoon ‘peak’ rush hours and will not arrive or depart from the site before 07.30 and after 18.00 weekdays. No deliveries will take place at the weekend.
Expected working hours during the construction phase are 07:00 – 18:00 Monday to Friday and 07:00 – 13:00 Saturday. No working is envisaged on Sundays or Bank Holidays unless by prior agreement with East Sussex County Council. The levels of traffic generated can be safely accommodated by the existing highway network and the proposals are therefore considered to satisfy Policy WMP26,
Southern Water has prepared a Construction Traffic Management Plan detailing the proposed route to the site for construction traffic and indicative arrangements for the storage of plant, equipment and materials that will be provided within the Site boundary.
Wheel washing will be provided where necessary within the site in accordance with standard contractors practice to prevent debris being deposited on the public highway.
Operational Vehicle Movements.
There will be a minor increase in the level of vehicle movements associated with the ongoing operation of the WTW, once the upgrade construction works have been completed. This increase will comprise an average of 1.5 additional HGV vehicles per month for chemical deliveries associated with ferric and polymer dosing and Microsand delivery. It is not considered that this increase will have any significant impact on the highway network or on residential amenity.
Land Quality.
A Preliminary Contaminated Land Risk Assessment (PCLRA) has been carried out and has been submitted with the planning application. The aim of the PCLRA is to identify any contamination sources in and within close proximity to the application site which may pose a risk to sensitive receptors.
The PCLRA concludes that overall the identified risks have been assessed as moderate to very low.
Archaeology / Cultural Heritage.
Policy WMP27 seeks to protect and enhance the historic environment including heritage assets. No Listed Buildings or Scheduled Monuments will be affected by the proposed development.
The application site and proposal have been assessed by an archaeologist and it has been concluded that the application site comprises land that is highly likely to have
been truncated by the installation of various infrastructure of the WTW and therefore has very low potential to yield any further archaeological evidence.
The proposed development is therefore unlikely to impact on archaeological features or deposits within the application site and will have no adverse impact on heritage assets. The proposals are therefore considered to be in accordance with Policy WMP27.
Flood Risk and Water Quality.
Policy WMP28a is aimed at ensuring that development does not have any adverse impact on flood risk, groundwater or water quality.
Fluvial Flooding.
The Environment Agency's flood plain maps show that the application site has a very low risk of flooding (Flood Zone 1). The proposed development is outside of the flood plain and will not result in a loss of flood plain storage or any increased risk of flooding elsewhere.
Surface Water Drainage.
Surface water from the majority of access roads on site will drain to ground, but the surface water around the inlet works and east of the screw lift pumping station all will be re-circulated to the head of the works via an existing works return pumping station. This will enable dirty surface water flows to be treated within the WTW processes and to be attenuated prior to discharge to the watercourse.
The proposed development will not result in any increased risk of fluvial or surface water flooding and is therefore in accordance with Policy WMP28a.
The primary objectives of the scheme are to enable compliance with new effluent discharge consents set by the Environment Agency and to contribute to improved water quality in the Pevensey Levels. The proposed development is therefore in accordance with Policy WMP28b, which seeks to protect the quality of water resources within the natural environment.
Stakeholder Engagement.
Southern Water will notify all local residents of the proposed development and likely impacts during the construction phase via a letter drop undertaken within the next two weeks.
6 CONCLUSION
The proposed development at Hailsham South WTW is necessary to ensure the WTW’s ongoing compliance with new discharge consent standard for phosphorous. The upgrade works are an integral part of a wider scheme that will ensure compliance with obligations under the Habitats Directives and Water Framework Directive to improve the water quality of the Pevensey Levels.
The proposed development is located within the existing WTW site and is relatively minor in scale in the context of the existing WTW plant and equipment. There will be no adverse impact on residential amenity or landscape character as a result of the proposed development and there will be no increase in flood risk. The proposals include a scheme of habitat enhancements that will ensure an overall net gain in biodiversity.
The proposed development is in accordance with the policies of the development plan and it is considered that planning permission should be granted.