Cyngor Bro Morgannwg
Vale of Glamorgan Council

Dinas Powys Community Council submits this technical objection to the proposed allocation of the Eastbrook site within the Vale of Glamorgan Replacement Local Development Plan (RLDP). While the Council recognises and welcomes several positive changes in the revised RLDP, the Eastbrook allocation remains fundamentally unsound due to unresolved constraints relating to:
• Flood risk and hydrology
• Highways and transport capacity
• Environmental and landscape impact
• Infrastructure limitations
• Deliverability and viability

The Eastbrook site lies within a complex hydrological catchment characterised by:
• Groundwater emergence
• Overland flow routes
• Low-permeability soils
• A history of significant flood events, including the 2020 incident
• Interactions between surface water, groundwater, and existing drainage systems
Natural Resources Wales (NRW) has repeatedly identified flood-risk concerns at this location, and the Council’s own evidence base acknowledges the need for detailed catchment-wide modelling before any development can be considered.

The RLDP currently lacks:
• Mandatory policy wording to secure pre-delivery of mitigation
• Requirements for catchment-wide modelling
• Guarantees that development will not increase flood risk elsewhere
• Mechanisms to ensure that mitigation is viable, deliverable, and enforceable

Without these safeguards, the allocation is unsound under the tests of:
• Soundness Test CE2 (coherence and effectiveness)
• Soundness Test CE4 (deliverability)
• Soundness Test CE3 (environmental protection)
This objection sets out:
1. The positive changes recognised in the revised RLDP
2. The continued reasons why the Eastbrook allocation remains unsound
3. A full technical hydrology and flood-risk chapter
4. Mandatory policy wording required to make the allocation sound
5. A formal request for written confirmation from the Vale of Glamorgan Council
6. Supporting diagrams (ASCII + placeholders)


SECTION 1. EXECUTIVE SUMMARY
Dinas Powys Community Council submits this technical objection to the proposed allocation of the Eastbrook site within the Vale of Glamorgan Replacement Local Development Plan (RLDP). While the Council recognises and welcomes several positive changes in the revised RLDP, the Eastbrook allocation remains fundamentally unsound due to unresolved constraints relating to:
• Flood risk and hydrology
• Highways and transport capacity
• Environmental and landscape impact
• Infrastructure limitations
• Deliverability and viability
The Eastbrook site lies within a complex hydrological catchment characterised by:
• Groundwater emergence
• Overland flow routes
• Low-permeability soils
• A history of significant flood events, including the 2020 incident
• Interactions between surface water, groundwater, and existing drainage systems
Natural Resources Wales (NRW) has repeatedly identified flood-risk concerns at this location, and the Council’s own evidence base acknowledges the need for detailed catchment-wide modelling before any development can be considered.
The RLDP currently lacks:
• Mandatory policy wording to secure pre-delivery of mitigation
• Requirements for catchment-wide modelling
• Guarantees that development will not increase flood risk elsewhere
• Mechanisms to ensure that mitigation is viable, deliverable, and enforceable
Without these safeguards, the allocation is unsound under the tests of:
• Soundness Test CE2 (coherence and effectiveness)
• Soundness Test CE4 (deliverability)
• Soundness Test CE3 (environmental protection)
This objection sets out:
1. The positive changes recognised in the revised RLDP
2. The continued reasons why the Eastbrook allocation remains unsound
3. A full technical hydrology and flood-risk chapter
4. Mandatory policy wording required to make the allocation sound
5. A formal request for written confirmation from the Vale of Glamorgan Council
6. Supporting diagrams (ASCII + placeholders)

The Community Council urges the Vale of Glamorgan Council to either:
• Remove the Eastbrook allocation from the RLDP, or
• Incorporate the mandatory policy wording and evidence requirements set out in this document.
Failure to do so will leave the RLDP vulnerable to challenge at Examination.

Examination.

SECTION 2 - INTRODUCTION
Dinas Powys Community Council (DPCC) submits this formal objection to the proposed allocation of the Eastbrook site (HG1 - KS2) within the Vale of Glamorgan Replacement Local Development Plan (RLDP). The Council recognises the importance of delivering sustainable housing across the Vale, and it acknowledges some of the positive changes made in the revised RLDP. However, the Eastbrook allocation remains fundamentally unsound due to unresolved and significant constraints relating to:
• Flood risk and hydrology
• Highways and transport capacity
• Environmental and landscape impact
• Infrastructure limitations
• Deliverability and viability
The Eastbrook site occupies a sensitive position within a complex hydrological catchment. The area is characterised by groundwater emergence, overland flow routes, low-permeability soils, and a history of significant flood events — most notably the 2020 incident, which affected properties downstream. Natural Resources Wales (NRW) has repeatedly highlighted concerns regarding flood risk at this location, and the Council’s own evidence base acknowledges the need for detailed catchment-wide modelling before any development can be considered.
Despite these known constraints, the RLDP does not currently include:
• Mandatory policy wording to secure pre-delivery of mitigation
• Requirements for catchment-wide modelling
• Guarantees that development will not increase flood risk elsewhere
• Mechanisms to ensure that mitigation is viable, deliverable, and enforceable
This objection sets out the failure to follow legal Consultation Procedural Soundness, the technical evidence, policy requirements, and mandatory safeguards necessary to make the RLDP sound. Without these safeguards, the allocation fails the tests of soundness, particularly:
• CE2 — Coherence and effectiveness
• CE3 — Environmental protection
• CE4 — Deliverability
This Council therefore requests either:
1. Removal of the Eastbrook allocation from the RLDP, or
2. Inclusion of the mandatory policy wording and evidence requirements set out in this document
Failure to address these issues will leave the RLDP vulnerable to challenge at Examination.

CHANGES IN THE REVISED RLDP
Dinas Powys Community Council (DPCC) recognises and welcomes some improvements made in the revised Replacement Local Development Plan (RLDP). These changes demonstrate a more balanced approach to growth and a clearer acknowledgement of environmental and infrastructure constraints across the Vale. DPCC considers the following amendments to be positive and constructive:
3.1 Reduction in Overall Housing Numbers
The reduction in the total housing requirement reflects a more realistic assessment of demographic trends, household formation rates, and deliverability across the plan period. This reduces pressure on constrained settlements such as Dinas Powys.
3.2 Greater Emphasis on Sustainable Locations
The revised RLDP places stronger emphasis on locating development where sustainable transport options exist. This aligns with national policy and reduces reliance on private car travel.
3.3 Strengthened Climate-Change and Flood-Risk Policies
The Council welcomes the enhanced policy framework relating to:
• Climate-change adaptation
• Flood-risk management
• Sustainable drainage (SuDS)
• Nature-based solutions
These changes reflect national guidance and NRW expectations.
3.4 Recognition of Infrastructure Constraints
The revised evidence base acknowledges that certain settlements – including Dinas Powys -face:
• Highway capacity limitations
• Public transport constraints
• Limited school and healthcare capacity
This recognition is essential for sound plan-making.

3.5 Improved Evidence Base
The updated background papers, including the Settlement Sustainability Assessment and the Infrastructure Assessment, provide a clearer picture of constraints and opportunities across the Vale.

SECTION 4 — CONTINUED OBJECTION TO THE EASTBROOK ALLOCATION
Despite recognising positive changes in the revised RLDP, Dinas Powys Community Council (DPCC) maintains a clear and evidence-based objection to the proposed allocation of the Eastbrook site (HG1 – KS2). DPCC email asked for clarification from the Vale planning office on the fact that the planning policy (dated 17 December 2025) stated ‘feedback received has helped to refine proposals for the sites in the deposit plan’. When asked at the consultation at Murchfield what the refinements were, the response was ‘there has not been any’.
The allocation remains unsound because the fundamental constraints affecting the site have not been resolved, mitigated, or fully understood.
DPCC’s objection is based on the following core issues:
4.1 Flood Risk and Hydrology
The Eastbrook site sits within a complex and sensitive hydrological catchment. Key concerns include:
• Groundwater emergence during prolonged wet periods
• Overland flow routes that cross the site and discharge toward existing residential areas
• Low-permeability soils that limit infiltration
• A history of significant flood events, including the 2020 incident
• Interactions between surface water, groundwater, and existing drainage systems
NRW has repeatedly raised concerns about flood risk at this location. The Council’s own evidence base acknowledges that catchment-wide modelling is required before any development can be considered. This modelling has not been undertaken.
4.2 Highways and Transport Capacity
Dinas Powys already experiences:
• Congestion on Cardiff Road
• Limited capacity at key junctions
• Insufficient public transport frequency
• High dependency on private car travel
The Eastbrook allocation would exacerbate these issues. No deliverable or funded mitigation has been identified.
4.3 Environmental and Landscape Impact
The site contributes to:
• Local landscape character
• Biodiversity connectivity
• Air quality
• Green infrastructure
• Natural drainage functions
Development would result in the loss of greenfield land that currently performs essential hydrological and ecological roles.
4.4 Infrastructure Limitations
Local infrastructure is already under pressure, including:
• Schools
• Healthcare provision
• Utilities
• Surface-water drainage systems
No evidence has been provided to demonstrate that these constraints can be resolved within the plan period.
4.5 Deliverability and Viability
The RLDP does not demonstrate that:
• Required flood-risk mitigation is technically feasible
• Mitigation is financially viable
• Mitigation can be delivered before development
• Mitigation will not increase flood risk elsewhere
Without this evidence, the allocation fails Soundness Test CE4 (deliverability).
Finally, there are questionable processes in the Consultation procedure that DPCC would like to question. These include:
Lack of Formalised Documentation and Transparent Feedback Loops: The consultation process currently lacks procedural transparency, specifically regarding the recording of public participation and the subsequent analysis of feedback. There is no evidence of formalised record-keeping for public attendance at engagement events, nor a transparent ledger of how individual resident comments were synthesised into the current Plan. Without clear feedback loops, it remains entirely unclear to stakeholders how local consultation responses have influenced site allocation decisions, compromising the Plan's legitimacy and accountability.
Significant Digital Barriers and Technical Complexity: The Council’s primary reliance on an "online-first" engagement strategy, through its consultation portal, has created substantial barriers to participation. The technical reports and modelling assumptions provided are often not easily interpretable by laypersons, limiting the ability of the community to effectively scrutinise the evidence base. The complexity of the account-creation process and the technical nature of the guidance notes have resulted in a disproportionate administrative burden that discourages meaningful public response.
Digital Exclusion and Demographic Disparity: The current consultation framework fails to adhere to the requirement that engagement must be "inclusive and accessible to all local groups", particularly those less likely to participate. Residents in Dinas Powys, specifically non-digitally native demographics and the elderly, face significant digital exclusion due to the lack of accessible summaries and the high level of technical literacy required to complete online forms. This lack of equitable access undermines the Council's duty to ensure a robust and representative evidence base.
Inflexible Scheduling and Inequitable Engagement Windows: The timing of the consultation periods has been identified as a factor that alienated or excluded significant portions of the local community. Despite formal requests from the DPCC for more accessible scheduling to facilitate wider public attendance, these requests were refused. Furthermore, there is a perceived pre-determination in the process, where preferred strategies and site directions appear to be announced prior to effectively engaging public opinion, rendering the subsequent consultation window a mere formality rather than a meaningful opportunity for influence.
Conclusion on Soundness: Due to these systemic failures in the Plan-making process, the RLDP fails the test of Effectiveness (CE2). Until the Council can demonstrate a fully transparent, accessible, and documented consultation process that genuinely reflects the lived experience of the community, the Plan cannot be considered fully justified or consistent with national policy regarding community involvement.
SECTION 5 — TRANSPORT AND HIGHWAYS

CONSTRAINTS

Transport and highways capacity remain a critical constraint for Dinas Powys and a central reason why the Eastbrook allocation is unsound. The settlement already experiences significant congestion with increasing air pollution (around critical areas such as schools), limited public transport provision, and constrained junction capacity. The RLDP does not demonstrate that these issues can be resolved within the plan period, nor does it provide evidence that the Eastbrook allocation can be delivered without exacerbating existing problems.

5.1 Existing Congestion and Network Stress

Dinas Powys suffers from chronic congestion, particularly along:

Cardiff Road The approach to the Merrie Harrier junction The route toward Penarth The route toward Barry

Peak-time delays are well-documented, and queueing frequently extends through residential areas. The network operates close to or at capacity during peak hours, leaving little room for additional traffic generated by new development.

5.2 Limited Public Transport Provision

Public transport options are constrained by:

Infrequent bus services Limited rail capacity at Eastbrook Station Poor integration between modes Lack of reliable alternatives to private car travel

The RLDP does not identify any committed or funded improvements that would materially increase public transport capacity.

5.3 Junction Capacity Constraints

Key junctions in and around Dinas Powys are already operating at or near capacity. These include:

Merrie Harrier junction Cardiff Road / Penlan Road Cardiff Road / Millbrook Road

No evidence has been provided to demonstrate that these junctions can accommodate additional traffic from the Eastbrook allocation.

5.4 Lack of Deliverable Mitigation

The RLDP does not include:

Funded highway improvements Committed public transport enhancements A deliverable transport strategy for Dinas Powys Evidence that mitigation is viable or achievable within the plan period

Without deliverable mitigation, the allocation fails Soundness Test CE4 (deliverability).

5.5 Cumulative Impact

The cumulative impact of, existing congestion, committed developments, background traffic growth and the Eastbrook allocation has not been assessed in a robust or comprehensive manner.

a. Unresolved Chronic Congestion on the A4055 Corridor:

The RLDP fails to demonstrate that the primary highway network serving Dinas Powys can accommodate the proposed level of growth without resulting in unacceptable congestion.

Existing Network Stress: The A4055 (Cardiff Road) and the approach to the Merrie Harrier junction are already characterized by "chronic congestion". Peak-time delays are well-documented, with queuing frequently extending through residential areas as the network operates at or near capacity.

Absence of Modelling: The Plan lacks transparent, settlement-specific junction capacity assessments or peak-hour traffic modelling for these key constraints. Without this evidence, the Council's assumption that an additional 250 units can be absorbed is technically unjustified.

The RLDP Preferred strategy requires the developer to provide "improvements to infrastructure, including the upgrading of highways. and utility networks" and provide "on and off-site measures" to provide safe linkages to Eastbrook Station and "upgrading of highways". It is unclear what if any specific and definitive instruction will be given to the developer and how the Council will monitor and ensure that appropriate objectives are achieved.

VOG Highways say that Persimmon cannot pencil in the 'secondary' or emergency access. Persimmon failed to do a traffic study to contest Highways' view. Another is no proposal to bring pedestrian/cycle access up to the Welsh Government standard. The suggested George's Row and Seel Park routes to Eastbrook Station and Camms Corner shopping area do not work. Highways point out this is a Welsh Government requirement for new developments.

In reference to Welsh Government's policies;

Policy conflict Fails PPW11 TAN 18, and the Fire and Rescue Services Act duty to maintain effective response capability. The proposal's reliance on a single access for a development of 250 dwellings is;

Contrary to PPW11 (safe, resilient access) Contrary to Tan 18 (avoid single points of failure) Contrary to Fire and Rescue operational requirements in Wales Contrary to Manual for Streets principles Contrary to established Welsh LHA practice Unsupported by appeal precedent.

The development therefore presents an unacceptable and avoidable risk to residents and emergency responders. A second access, or at minimum a fully engineered emergency only route, is essential to make the scheme safe and policy compliant.

b. Cumulative Traffic Flows from Regional RLDP Growth:

The RLDP directs a significant portion of the 7,890 required dwellings to settlements east of Dinas Powys, including major allocations in Barry and Penarth.

Impact of Neighbouring Allocations: Developments such as Upper Cosmeston Farm in Penarth (576 units) and the proposed growth in Barry (686 units) will significantly increase commuter volumes along the A4055, which serves as the primary arterial route to Cardiff.

Commuter Dependency: Data identifies Cardiff as the destination for 63.6% of all commuters from the Vale traveling by car. The RLDP fails to robustly assess the cumulative impact of background traffic growth, committed developments, and the Eastbrook allocation on the Dinas Powys road network. The Eastbrook allocation is fundamentally car-dependent due to infrequent bus services and limited modal integration. Furthermore, the RLDP does not identify any funded or committed highway improvements for the A4055 (Cardiff Road) or the Merrie Harrier junction, both of which are already operating at or near capacity. This lack of deliverable mitigation contradicts the transport objectives.

c. Failure of Active Travel and Pedestrian Infrastructure: The Plan relies on "sustainable transport options" to justify the Eastbrook site, yet the physical infrastructure is fundamentally non-compliant with inclusive design standards: Pavement Capacity and Safety: Existing pedestrian routes connecting the site to the village centre, are insufficient in width to accommodate double buggies or wheelchairs. These routes are further obstructed weekly by refuse collection and recycling bags, forcing vulnerable pedestrians - including those with single buggies or small children - to navigate restricted and unsafe spaces.

During the consultation (6th February 2026) Vale officers were asked if they had walked the proposed active travel route along Cardiff Road. We were told they had not. Photos below show how narrow the pavement is and this does not meet with the Active Travel Guidelines. There is no capacity to widen this route. In addition, the other proposed route via Powys Gardens involves a very steep hill. Would this be accessible for people with mobility scooters or mobility issues. It would also be a hazard in icy weather. This route also incorporates an alleyway which is not visible from start to finish with a 90 degree angle and no lighting. This is a safety concern. Another route is via some garages which are off George's Row. This is not and adopted road by the Vale and therefore not within their remit to propose it as an active travel route.

Eastbrook Railway Station Accessibility: While the station is within a 10-minute walk, it suffers from a critical "accessibility gap." Only one platform is accessible to residents with limited mobility, prams, or cycles. Due to the absence of a lift to the opposite platform, these residents must undertake a one-mile detour via local roads to access rail services, rendering the "sustainable" rail link effectively inaccessible to a significant portion of the demographic. Feedback from the Vale drop in session (6th February 2026), revealed that when residents mentioned that mothers with prams and people with mobility issues can't use the Eastbrook station, The response was 'it's fine for the majority'. When asked about the minority and about them being discriminated against there was no response. When looking at Active Travel Guidelines it references the Equality Act 2010. What dialogue has the Vale had with organisations representing people with protected characteristics.
d. Deficiencies in Public Transport Provision: The reliance on "good bus links" is not supported by current service levels:

Infrequent Bus Services: Dinas Powys is characterized by infrequent bus services that do not provide a reliable alternative to private car travel.

Lack of Mitigation: The RLDP does not identify any committed or funded improvements to bus frequency or capacity, ensuring that the Eastbrook development will remain car- dependent and exacerbate existing A4055 corridor failures. Without a committed and funded scheme to address the documented "chronic congestion" at the Merrie Harrier junction and A4055, the allocation fails the deliverability standards outlined in the RLDP Section 7.8.

Mandatory Policy Wording Required for Soundness: to address these obstacles and ensure they are not sidelined during the development process, the RLDP must include the following:

Enforceable policy wording to meet Soundness Tests CE2 (Effectiveness) and CE4 (Deliverability): Policy TR-DNP: Enforceable Transport and Accessibility Mitigation

Development at Eastbrook (HG1 - KS2), in the opinion of DPCC, should not be permitted unless the following criteria are met and delivered in advance of occupation:

1. Corridor Capacity and Cumulative Modelling: A comprehensive Cumulative Transport Assessment is completed and approved, demonstrating that the A4055 and Merrie Harrier junction can accommodate traffic from Eastbrook in combination with committed growth in Barry and Penarth without exceeding statutory capacity or safety limits. During the consultation Vale officers admitted that the road is already over capacity.

2. Eastbrook Station Bilateral Access: Legally binding funding and a delivery program are secured for the installation of a lift or accessible bridge at Eastbrook Railway Station to ensure bilateral platform access for all users, removing the current one-mile detour requirement.

However, having been in discussion with the Department of Transport, they have no plans to make any improvements to the station with regard to access.

3. Statutory Inclusive Pedestrian Widths: All off-site pedestrian linkages to the village centre and station are widened to meet statutory inclusive design standards, ensuring a minimum effective width for simultaneous passage of double buggies and wheelchairs. In line with the Active Travel Act has the Vale carried out an Equality impact assessment (EQIAs). Proposed active travel routes do not meet the criteria.

4. Operational Access Management: A Pedestrian Management Plan is approved, demonstrating how safe passage for prams and wheelchairs will be maintained during weekly refuse and recycling collections.

5. Secured Bus Enhancements: Written confirmation and funding are secured to increase bus service frequency to provide a genuine, high-frequency alternative to private car travel for Cardiff-bound commuters. Has a WelTAG survey has been carried out? Due to the volume of traffic through Dinas Powys a bus service is thinking of reducing the service as so much time is spent in static traffic. Evidence that these routes can be preserved or managed safely including evidence of Equality Impact Assessment (EQIAs). Evidence of the Active Travel Wales Act 2013. What reasonable measures have you taken to include children and young people in the planning and implementation and review of the decision-making process? Conclusion: In the absence of this 'mandatory wording' and the required 'technical modelling', the Eastbrook allocation is unsound. It ignores the physical reality of the infrastructure, the lived experience of residents on the A4055, and the cumulative traffic pressures generated by the RLDP's own regional growth strategy. Based on a review of the Vale of Glamorgan RLDP Preferred Strategy and the Final Review Report, the following technical objection focuses on the proposed delivery of 250 houses at the Eastbrook site. This objection highlights the failure to align the housing mix with local demographic needs, the lack of transparency regarding infrastructure funding, and the questionable justification for further large-scale growth in Dinas Powys. 5.6 Summary

The transport and highways evidence base does not demonstrate that the Eastbrook allocation can be delivered without causing severe impacts on the local network. The RLDP therefore fails to meet the requirements of national planning policy, which requires development to be located where sustainable transport options exist and where the impact on the transport network can be effectively mitigated.

SECTION 6 — ENVIRONMENTAL AND LANDSCAPE IMPACT

The Eastbrook allocation sits within a sensitive landscape setting that performs important ecological, visual, and hydrological functions. Development of this site would result in the permanent loss of greenfield land that currently contributes to the environmental quality and character of Dinas Powys. The RLDP does not demonstrate that these impacts can be acceptably mitigated.

6.1 Landscape Character and Visual Impact

The site forms part of the green corridor that separates Eastbrook from adjoining areas. It contributes to:

The semi-rural character of the settlement edge Views from public rights of way The visual transition between built form and open countryside The sense of openness and separation between neighbourhoods

Development would introduce built form into an area that currently provides visual relief and contributes to local identity.

6.2 Biodiversity and Habitat Connectivity

The site supports:

Hedgerows Grassland habitats Mature trees Wildlife corridors connecting to wider green infrastructure

These features provide habitat for a range of species and contribute to ecological connectivity across the settlement. Development would fragment these habitats and reduce biodiversity value.

6.3 Green Infrastructure Functions

The land performs several important green-infrastructure functions, including:

Natural drainage and infiltration Groundwater recharge Overland flow conveyance Urban cooling Carbon sequestration

These functions are particularly important given the site's hydrological sensitivity.

6.4 Impact on Local Amenity

The site provides informal amenity value for local residents, including:

Views Open space character A sense of separation between built areas

Development would reduce these qualities and alter the character of the local environment.

6.5 Lack of Robust Mitigation Evidence

The RLDP does not provide:

A landscape and visual impact assessment A biodiversity net-gain strategy A green-infrastructure plan Evidence that ecological impacts can be mitigated or compensated A clear demonstration that the site can deliver net environmental benefits

Without this evidence, the allocation fails Soundness Test CE3 (environmental protection).

Statutory Ecological and Environmental Impacts: The development will cause detrimental impacts on protected European sites and irreplaceable local habitats like Ancient Woodland.

Independent Source Verification:

The HRA of the Preferred Strategy (2023) explicitly flags Site 440 (HG1 - KS2 Land North of Dinas Powys) as being only 2.6km from the Severn Estuary SAC/SPA/Ramsar.

The HRA concludes that "Mitigation is Required" for this site because it falls within the core recreational catchment of the Estuary. It recommends that the RLDP must contribute to Strategic Access Management and Monitoring (SAMM) and the provision of alternative green spaces (SANG) to protect the integrity of the Estuary.

NRW's ECOR documents that previous attempts to build flood storage in the area were opposed by the Woodland Trust because they would threaten Ancient Woodland, which is described as an "irreplaceable natural resource".

Prematurity regarding Green Infrastructure (Policy SP10 / MG18): Section 7.10 of the Review Report mandates a new Green Infrastructure Assessment (GIA) to comply with updated national policy (PPW) and the Section 6 duty to enhance biodiversity.

Grounds for Objection: The Review Report highlights that this GIA is intended to "inform plan policies and policy wording". Furthermore, independent evidence confirms the Eastbrook area is subject to Policy MG18 (Green Wedge), where development that prejudices the "open nature of the land" is prohibited. Allocating Eastbrook before the completion of the settlement-specific GIA and a formal review of the Green Wedge's integrity contradicts the sequential approach described in Section 7.

To prevent irreversible damage to the environment and ensure the ecological integrity of Dinas Powys, the RLDP must move beyond high-level assumptions. Based on the evidence in the sources, the following measures are strictly necessary to protect the local and regional environment from the impacts of the proposed Eastbrook development:

1. Mandatory Hydrological Safeguards: The Eastbrook site sits within a complex catchment characterized by groundwater emergence and low-permeability soils. To prevent increased flood risk to the environment and existing properties, the following must be delivered:

Catchment-Wide Hydraulic Modelling: A full model, agreed with Natural Resources Wales (NRW), must be completed to assess surface water, groundwater, and overland flow. This model must specifically incorporate data from the 2020 flood event to demonstrate "no increase in flood risk" to any property within the catchment.

Preservation of Natural Drainage: Existing overland flow routes and groundwater pathways must be preserved, enhanced, or appropriately managed to prevent the displacement of water into sensitive habitats or residential areas.

Proven SuDS Feasibility: A detailed study is required to prove that Sustainable Drainage Systems (SuDS) can operate effectively given the site's documented high groundwater levels and limited infiltration capacity.

2. Protection of Irreplaceable Habitats: The development area includes and is adjacent to Ancient Woodland and Sites of Importance for Nature Conservation (SINC), such as Coed Clwyd-Gwyn and Case Hill Wood.

Avoidance of Loss: Ancient woodland is an "irreplaceable natural resource". To prevent environmental damage, the Council must demonstrate that development will not result in its loss or deterioration, as "no amount of tree planting" can replace the unique biodiversity and interactions developed over centuries in these woods.

Connectivity and Resilience: The Plan must secure a Green Infrastructure Plan that maintains wildlife corridors and prevents the fragmentation of habitats for protected species, including bats, otters, and dormice.

Hydrological Stability: Measures must ensure that the development does not cause nutrient enrichment or pollution of woodland soils via sediment-heavy floodwaters, which can destabilize trees and kill overwintering species.

3. Mitigation for European Protected Sites: The Habitats Regulations Assessment (HRA) confirms that the Eastbrook site (Site 440 - HG1 - KS2) has "medium-high suitability" as off-site supporting habitat for the Severn Estuary SPA/Ramsar. To prevent an adverse effect on the integrity of this site, the following is necessary:

Bird Surveys and Evidence: The applicant must provide non-breeding bird surveys covering autumn, winter, and spring to determine if the site constitutes "functionally linked habitat" (supporting >1% of a qualifying population). Enforceable Mitigation: If significant populations are identified, the development must include avoidance measures and be assessed through a project-specific HRA.
4. Air Quality and Carbon Mitigation: Dinas Powys suffers from chronic congestion on the A4055, yet location-specific air quality modelling is absent from the evidence base. Cumulative Impact Modelling: To prevent harm to human health and the environment, the Council must conduct detailed air quality modelling that tests the cumulative effect of growth in Eastbrook alongside regional growth in Barry and Penarth. Decarbonisation Standards: New development must contribute to the Council's Net Zero 2030 ambition through siting and design that prioritizes active travel over car dependency, thereby reducing vehicle emissions.
5. Infrastructure Pre-Delivery: To prevent environmental harm from overloaded systems, essential infrastructure must be phased correctly: Wastewater Capacity: A settlement-specific assessment must prove the consented capacity of local wastewater treatment works is sufficient to prevent sewer surcharging and the discharge of untreated water into local watercourses. Phasing Requirements: All required infrastructure upgrades-including drainage, utilities, and highways mitigation-must be delivered and operational in advance of occupation. Conclusion: Without these mandatory policy safeguards and the completion of the required technical evidence base, the Eastbrook allocation remains unsound and poses a significant risk of irreparable damage to the environment of Dinas Powys.

SECTION 7 — INFRASTRUCTURE CAPACITY AND SERVICE LIMITATIONS

Infrastructure capacity is a critical determinant of whether a site is suitable and deliverable within the RLDP period. In the case of Eastbrook, the evidence demonstrates that essential infrastructure in Dinas Powys is already under significant pressure. The RLDP does not provide clear, funded, or deliverable solutions to these constraints, nor does it demonstrate that the Eastbrook allocation can be supported without unacceptable impacts on existing residents.

7.1 Education Capacity

Local schools are operating at or near capacity. Key issues include:

Limited availability of primary school places Pressure on secondary school capacity within the wider catchment. No identified funding or land for expansion No evidence that developer contributions would be sufficient or timely

The RLDP does not demonstrate that additional demand generated by the Eastbrook allocation can be accommodated.

Education Provision and School Oversubscription: The RLDP identifies Dinas Powys as a sustainable location for growth, yet it fails to provide settlement-specific evidence that local schools can absorb the additional demand from 250 new homes.

Capacity Deficit: Local primary and secondary schools are already operating at or near peak capacity. Existing data indicates limited availability of primary school places and significant pressure on secondary school capacity within the wider catchment area.

Lack of Expansion Capability: There is no identified land or secured funding for the physical expansion of these schools. The Plan provides no evidence that developer contributions (Section 106) would be sufficient or timely enough to resolve these standard-of-service deficits prior to the occupation of new homes.

Policy Inconsistency: Proceeding with the allocation without a confirmed delivery plan for school places is contrary to Planning Policy Wales, which requires growth to be directed only where essential infrastructure is available or can be secured.

To ensure that education capacity is not "overridden" by strategic regional data, the following enforceable requirement should be incorporated into Policy SP4 KS2: Policy ED-DNP: Mandatory Local Education Capacity Confirmation "Development at Eastbrook will not be permitted unless:

1. Direct Local School Consultation: A formal School Capacity Impact Report is submitted, based on direct consultation with the Headteachers and Governing Bodies of the specific schools within the Dinas Powys catchment area.

2. Verified Local Headroom: The report must provide written confirmation from these local institutions that they have the physical classroom space and staff capacity to accommodate the projected pupil yield from the development without increasing class sizes beyond statutory limits or compromising educational standards.

3. Local vs. Authority Primacy: High-level strategic projections from the Education Authority shall be deemed insufficient evidence of deliverability if they are contradicted by the operational data and physical constraints identified by the local schools themselves.

4. Pre-commencement Delivery: Any required physical expansions or new school infrastructure must be fully funded, completed, and operational prior to the occupation of the first dwelling to ensure places are available when needed

7.2 Healthcare Provision

Healthcare services in Dinas Powys and the surrounding area face:

Limited GP medical centre capacity Long waiting times Pressure on community health services No committed investment to expand provision

The medical services serving Dinas Powys are currently at capacity, and the RLDP fails to identify a mechanism to expand provision in line with population growth. Whilst it's understood that the Vale Council have spoken with the local health board. Unfortunately, there has been no consultation with single medical centre in Dinas Powys. They would be best placed to comment on the significant impact of additional housing on their provision of healthcare which is already stretched well beyond its limits.

GP and Dental Strain: Local residents already experience limited medical GP capacity and long waiting times. Existing community health services are under "significant pressure," and there is no committed investment to expand these facilities across Dinas Powys.

Lack of Local Consultation: While the Council claims to work at a high level with the Cardiff and Vale University Health Board, there has been no direct consultation with the local Health Centre serving Dinas Powys. Consequently, the Plan does not account for the technical and operational realities of a surgery that is already at capacity and cannot absorb the projected increase in patient numbers. A direct operational capacity verification from the Dinas Powys Medical Centre - current patient list size is around 11k which has increased significantly due to the closure of a nearby practice and therefore the practice is experiencing a reduced operational capacity. Any additional housing would put further strain on the practice demands and waiting times for local residents and would mean the practice moves further outside the idealised UK average (1 GP per 1,400-1,600 patients).

Health Inequality Risk: Without settlement-specific planning and confirmed provision, the proposed growth risks reducing access to healthcare for both existing and new residents, directly undermining the health and well-being objectives set out in Policy SP6.

7.3 Utilities and Drainage

Utility networks in the area face known constraints:

Surface-water drainage systems are already under pressure Foul drainage capacity is limited Welsh Water has previously raised concerns about network capacity in the settlement No evidence has been provided to demonstrate that upgrades are deliverable within the plan period

Given the site's hydrological sensitivity, drainage capacity is a critical issue.

7.4 Emergency Services and Community Infrastructure

The Eastbrook allocation would place additional pressure on:

Emergency services Community facilities Local open space Recreational infrastructure

No evidence has been provided to demonstrate that these services can absorb additional demand.

7.5 Funding and Deliverability

The RLDP does not identify:

Committed funding a delivery programme a mechanism to secure timely infrastructure upgrades Evidence that developer contributions would be viable or sufficient

Without this, the allocation fails Soundness Test CE4 (deliverability).

7.6 Summary

Reference Environment and Regeneration Scrutiny Committee 14 January 2025 it states. 'Produce sustainable Urban Drainage Solutions'. No progress due to funding and competing priorities. Infrastructure in Dinas Powys is already excessively stretched. The RLDP does not demonstrate that the Eastbrook allocation can be supported without a significant adverse impact on existing residents. Nor does it provide evidence that required upgrades are viable, deliverable, or fundable within the plan period.

SECTION 8 — HYDROLOGY AND FLOOD-RISK ANALYSIS (FULL TECHNICAL CHAPTER)

The Eastbrook site lies within a hydrologically sensitive catchment characterised by complex interactions between surface water, groundwater, overland flow, and existing drainage infrastructure. The site has a documented history of flooding, including the significant 2020 event, and Natural Resources Wales (NRW) has repeatedly raised concerns about the potential for development to increase flood risk elsewhere. At the Vale Council's drop-in session (6th Feb), there was a lack of knowledge that there is a Holy Well on the Eastbrook site, referenced in the NRW report on flooding (NRW Dinas Powys Flood Risk Management Scheme OBC page 10).

This section provides a technical assessment of the hydrological constraints affecting the site and sets out the evidence required to ensure that any development does not exacerbate flood risk to existing properties.
8.1 Catchment Overview
The Eastbrook site forms part of a small but highly responsive catchment. Key characteristics include: Low-permeability soils, resulting in rapid surface-water runoff Groundwater emergence during prolonged wet periods Overland flow routes crossing the site and discharging toward existing residential areas Limited infiltration capacity, reducing the effectiveness of SuDS Downstream constraints within the existing drainage network The catchment responds quickly to rainfall, with limited storage capacity and a high risk of exceedance during intense or prolonged events.

8.2 Hydrological Function of the Site

The site currently performs several important hydrological functions:

Attenuation of surface water during storm events Conveyance of overland flow along natural depressions Groundwater emergence and dissipation Reduction of peak flows entering downstream drainage systems Natural infiltration, albeit limited by soil type

Development would significantly alter these functions, increasing runoff rates and volumes unless substantial mitigation is provided.

8.3 Overland Flow Routes

Multiple overland flow routes cross the site. These routes convey water:

From higher ground to the north and east Across the site during heavy rainfall Toward existing residential areas downstream

Below is an ASCII-style conceptual diagram illustrating the simplified flow pattern:

Code [Higher Ground]

V

Overland Flow Across Site

V [Existing Residential Area] (Downstream Flood Receptors)

Diagrammatic representation for illustrative purposes only - not to scale.

These routes are active during moderate and heavy rainfall events and were observed during the 2020 flood incident.

8.4 Groundwater Emergence

Groundwater emergence has been recorded on and around the site during:

Prolonged wet periods High antecedent moisture conditions Winter months

This groundwater emergence contributes to:

Saturated ground conditions Reduced infiltration capacity Increased surface-water runoff Localised flooding

Any development must demonstrate that it will not alter groundwater pathways or increase groundwater-related flood risk.

8.5 The 2020 Flood Event

The 2020 flood event provides clear evidence of the site's hydrological sensitivity. During this event:

Overland flow crossed the site Groundwater emergence contributed to saturated conditions Downstream properties experienced flooding Existing drainage systems were overwhelmed

The event demonstrated that:

The catchment is highly responsive The site plays a critical role in attenuating and conveying water Development could increase flood risk unless carefully managed

The RLDP does not include any analysis of the 2020 event, nor does it require developers to assess its implications.

8.6 NRW Position and Evidence Requirements

NRW has consistently raised concerns about:

Surface-water flood risk Groundwater interactions Overland flow routes Downstream flood receptors Lack of catchment-wide modelling

NRW has advised that catchment-wide hydraulic modelling is required to:

Understand baseline conditions Assess the impact of development Identify necessary mitigation Ensure no increase in flood risk elsewhere

This modelling has NOT been undertaken.

The RLDP flood risk evidence base is functionally obsolete. It relies on the 2013 Local Flood Risk Management Strategy and a September 2020 NRW decision to abandon capital mitigation. Both of these were rendered technically invalid by the scale of the December 2020 flood event. NRW has not formally reviewed or updated a mitigation strategy for this catchment in the 11 years since the original LFRMS was published. NRW's last formal review of flood mitigation for this area was the September 2020 ECOR, which predates the 2020 flood. No post-flood mitigation review or catchment modelling incorporating the 2020 data has been undertaken.

8.7 Limitations of SuDS on This Site

While SuDS are a national requirement, their effectiveness on this site is constrained by:

Low-permeability soils High groundwater levels Limited infiltration potential Steep localised gradients Overland flow pathways that cannot be obstructed

SuDS alone cannot mitigate the hydrological impacts of development without:

Catchment-wide modelling Detailed design Pre-delivery of mitigation Long-term maintenance arrangements

8.8 Required Mitigation Measures

To ensure no increase in flood risk, the following mitigation measures would be required:

Catchment-wide hydraulic modelling Preservation of overland flow routes On-site attenuation with exceedance routing Groundwater management measures Upgrades to downstream drainage systems Pre-delivery of mitigation before development commences

The RLDP does not secure any of these measures.

8.9 Summary

The Eastbrook site is hydrologically complex and highly sensitive. Without detailed catchment-wide modelling and enforceable mitigation, development would increase flood risk to existing properties. The RLDP does not provide the evidence or policy framework required to ensure that the allocation is sound.

Natural Resources Wales (NRW) has not formally reviewed or updated its flood mitigation plans for Dinas Powys since the major flood event on December 23, 2020. The evidence base reveals a critical gap between the last strategic planning and the reality of the 2020 disaster:

1. The "2013 Strategy" Precedent: The Local Flood Risk Management Strategy (LFRMS) for the Vale of Glamorgan is dated December 2013. While this document identified Dinas Powys as being at "significant future risk," it is now over a decade old and predates both the 2020 flood and updated climate change projections. Reference Environment and Regeneration Scrutiny Committee 14 January 2025 it states. 'Implement a flood risk management plan and shoreline management plan'. No progress due to funding and competing priorities.

The above shows that the concerns of residents and flood issues in Dinas Powys are not being taken seriously.

2. Pre-Flood Rejection of Mitigation (September 2020): The most recent formal NRW assessment regarding a strategic flood scheme for Dinas Powys - the Environmental Constraints and Opportunities Record (ECOR) - was completed in September 2020, just three months before the major flood event.

A "Walkaway" Conclusion: In that pre-flood report, NRW concluded it was "unable to justify a capital flood scheme" for Dinas Powys because it was deemed only "marginally cost-beneficial".

Status Quo: NRW stated they would continue only with "business as usual" (manual channel clearing) rather than any new structural mitigation.

3. No Post-Flood Review of Mitigation: While NRW conducted "flood reconnaissance" in January 2021 and contributed to the Section 19 Flood Investigation Report (published in November 2021), these were investigative documents rather than updated mitigation plans. Missing Evidence Base: The sources explicitly state that "no catchment-wide hydraulic modelling has been undertaken" that incorporates the actual data and observations from the December 2020 event.

Outstanding Recommendations: The Section 19 report concluded by recommending that NRW "consider the viability of options to reduce flood risk," which confirms that such a review had not yet taken place as of late 2021.

4. RLDP Soundness Failure: The current RLDP is being challenged because it relies on high- level strategic data that ignores the 2020 flood event entirely.

The objection drafts note that the RLDP "does not include any analysis of the 2020 event" nor does it require developers to assess its implications.

Without an NRW-approved model that accounts for the 98 internal property floodings observed in 2020, the Council cannot technically prove that 250 additional houses will not increase flood risk elsewhere.

In conclusion, in this respect, the RLDP is unsound because its flood evidence base is functionally obsolete. It relies on a 2013 Strategy and a September 2020 NRW decision to abandon mitigation-both of which were rendered invalid by the scale of the December 2020 flood. NRW has not reviewed or modelled a new mitigation strategy for the catchment since that event occurred, leaving the settlement and the proposed site without any verified protection.

SECTION 9 — MANDATORY POLICY WORDING REQUIRED TO MAKE THE RLDP SOUND

To ensure that the Eastbrook allocation is sound, the RLDP must include explicit, enforceable, and unambiguous policy wording that secures the necessary hydrological, environmental, and infrastructure safeguards. Without this wording, the allocation fails the tests of soundness - particularly CE2 (coherence and effectiveness), CE3 (environmental protection), and CE4 (deliverability).

The following policy wording is mandatory to ensure that development does not increase flood risk elsewhere and that mitigation is viable, deliverable, and enforceable.

9.1 Mandatory Flood-Risk Policy Wording

The RLDP must include the following:

Policy FR-X: Catchment-Wide Flood-Risk Assessment (Mandatory Requirement) Development at Eastbrook (HG1 - KS2) will not be permitted unless:

1. A full catchment-wide hydraulic model has been prepared, agreed with Natural Resources Wales (NRW), and approved by the Local Planning Authority (LPA). 2. The model demonstrates no increase in flood risk to any existing property within the catchment for all relevant storm events, including climate-change allowances. 3. All required mitigation measures are: Technically feasible Financially viable Deliverable within the plan period Secured through planning conditions or legal agreement 4. All mitigation measures are delivered prior to the commencement of development. 5. Overland flow routes, groundwater pathways, and natural drainage functions are preserved, enhanced, or appropriately managed. 6. A long-term management and maintenance plan for all SuDS and flood-risk infrastructure is secured.

9.2 Mandatory Groundwater and Overland Flow Policy Wording Policy FR-Y: Groundwater and Overland Flow Protection Development proposals must:

Demonstrate that groundwater emergence will not be exacerbated Preserve all existing overland flow routes Provide exceedance routing that avoids existing residential areas Incorporate groundwater-resilient design measures Avoid any obstruction of natural drainage pathways

No development will be permitted unless these requirements are met in full.

9.3 Mandatory SuDS Policy Wording

Policy SuDS-X: Sustainable Drainage Requirements

All development must:

Provide SuDS designed in accordance with national standards Demonstrate that infiltration-based SuDS are viable, or provide alternatives where infiltration is not feasible Include attenuation sized using catchment-wide modelling outputs Provide exceedance routing that avoids downstream receptors Secure long-term maintenance arrangements

SuDS must be operational before any dwelling is occupied.

9.4 Mandatory Infrastructure Delivery Policy Wording

Policy INF-X: Infrastructure Delivery and Phasing

Development at Eastbrook (HG1 - KS2) will not be permitted unless:

All required infrastructure upgrades (education, healthcare, utilities, drainage, highways) are identified Funding is secured Delivery is guaranteed within the plan period Infrastructure is delivered in advance of occupation

The RLDP must demonstrate that infrastructure delivery is viable and enforceable.

9.5 Summary

Without the mandatory policy wording set out above, the RLDP:

Does not secure the evidence required to assess flood risk Does not guarantee that mitigation will be delivered Does not ensure that development will not increase flood risk elsewhere Does not demonstrate deliverability Fails multiple tests of soundness

The inclusion of this wording is essential to ensure that the Eastbrook allocation is sound, effective, and compliant with national policy.

SECTION 10 - HOUSING DELIVERY AND

DEMOGRAPHIC MISALIGNMENT

While Section 4 of the review of the RLDP focuses on high-level data across the Vale, DPCC utilises these specific evidence base shifts to argue that the Eastbrook allocation is no longer justified under the new planning context. The Vale Council have removed S106 affordable housing money (£1m) from Dinas Powys, as we were told there are no housing developments planned and the funds were reallocated to Myrtle Close which negates the suggestion in the RLDP that there is a need for affordable housing in Dinas Powys. Therefore the development should be removed from the RLDP or the S106 moved back to Dinas Powys.

Mapping Section 4 Evidence to Dinas Powys Objections:

1. Review Report Ref: 4.1.1 4.1.11 (Population and Household Projections): Review Report Context: This section details the transition from 2011-based projections to the more recent 2018-based Welsh Government projections, noting a "significant departure" from the evidence that underpinned the original LDP.

Relationship to Dinas Powys: DPCC explicitly links this update to their objection in Ref: this response section 3.1 (Reduction in Overall Housing Numbers). We argue that the more realistic assessment of demographic trends and the subsequent reduction in the total housing requirement for the Vale should "reduce pressure on constrained settlements such as Dinas Powys". We maintain that with lower overall demand, the "unnecessary" and high-risk allocation at Eastbrook should be the first to be removed.

2. Review Report Ref: 4.2.1 - 4.2.15 (Economic Considerations and Employment): Review Report Context: This section reviews the employment land supply and economic growth scenarios for the 2021-2036 period. It lists major strategic employment sites, none of which are located within Dinas Powys.

Relationship to Dinas Powys: In the Preferred Strategy and subsequent objections, Dinas Powys is categorised as a Primary Settlement. DPCC points out that since the Review Report identifies economic and employment growth as being concentrated in the "Strategic Growth Area" (Barry, Rhoose, St Athan), allocating 250 houses in Dinas Powys creates a car-dependent commuter settlement. This contradicts the Review Report's emphasis on aligning housing with major employment hubs to reduce private car travel.

3. Review Report Ref: 4.3.1 (Conclusion on Evidence Base Changes): Review Report Context: The report concludes that the updated population, economic, and legislative evidence represents a "significant departure from that which informed the existing LDP" and supports the need for a full replacement plan.

Relationship to Dinas Powys: DPCC uses this conclusion to support their Ref: this response section 3.5 (Improved Evidence Base) objection. We argue that because the Vale Council's own Review Report acknowledges a "significant departure" in the evidence base, the Council must also acknowledge that the previous assumptions
regarding the deliverability of Eastbrook are now invalid. Specifically, they point to the "improved picture of constraints" (such as the 2020 flood event) that must be re- evaluated under the "robust and transparent" evidence standards called for in Section 4 of this response. Summary of Evidence Linkage: Section 4 of the Review Report provides the technical justification for a "Realistic assessment" of growth. DPCC's position is that if the Vale Council follows its own evidence in Section 4 - which shows lower housing need and a concentration of employment elsewhere - it cannot logically justify a large-scale housing development on a high-flood-risk greenfield site in a "constrained settlement" like Dinas Powys.

SECTION 11 - REQUIRED EVIDENCE FROM THE VALE OF GLAMORGAN COUNCIL

For the Eastbrook allocation to be considered sound, DPCC request that the Vale of Glamorgan Council must provide clear, transparent, and technically robust evidence demonstrating that the site is:

Deliverable Developable Environmentally acceptable Hydrologically safe Supported by adequate infrastructure

At present, this evidence is absent from the RLDP. The following items are required before the allocation can be considered sound.

11.1 Catchment-Wide Hydraulic Modelling

The Council must provide:

A full catchment-wide hydraulic model Prepared in consultation with NRW Covering surface water, groundwater, and overland flow Including climate-change allowances Assessing the 2020 flood event Demonstrating no increase in flood risk to existing properties

This modelling is essential to understand baseline conditions and the impact of development.

11.2 Groundwater Assessment

A detailed groundwater assessment is required to:

Map groundwater emergence zones Assess seasonal variations Identify groundwater pathways Determine the impact of development on groundwater levels Demonstrate that development will not exacerbate groundwater flooding

No such assessment has been provided.

11.3 Overland Flow Route Mapping

The Council must provide:

High-resolution mapping of overland flow routes Assessment of exceedance pathways Identification of downstream receptors

This is particularly important given the 2020 flood event.

11.4 SuDS Feasibility Study

A SuDS feasibility study must be provided to:

Assess infiltration potential Identify viable SuDS options Determine attenuation requirements Demonstrate that SuDS can operate effectively given soil and groundwater constraints

Without this, SuDS cannot be assumed to mitigate flood risk.

11.5 Downstream Drainage Capacity Assessment

The Council must provide:

A full assessment of downstream drainage capacity Identification of constraints Required upgrades Funding mechanisms Delivery timescales

This is essential to ensure that development does not overload existing systems.

11.6 Infrastructure Delivery Plan (IDP) Evidence

The IDP must demonstrate:

Education capacity solutions Healthcare capacity solutions Utilities upgrades Drainage improvements Highways mitigation Funding sources Delivery timescales Viability

At present, the IDP does not provide this level of detail.

11.7 Transport Assessment

A comprehensive transport assessment is required to: Assess cumulative impacts Model peak-time flows Identify junction constraints Provide deliverable mitigation Demonstrate that sustainable transport options exist No such assessment has been provided. 11.8 Landscape and Ecology Evidence

The Council must provide: A landscape and visual impact assessment A biodiversity net-gain strategy A green-infrastructure plan Evidence that ecological impacts can be mitigated These are essential to comply with national policy.
11.9 Summary

The RLDP currently lacks the evidence required to demonstrate that the Eastbrook allocation is: Safe Deliverable Environmentally acceptable Supported by adequate infrastructure Until this evidence is provided, the allocation remains unsound.

SECTION 12 — SCHEMATIC DIAGRAMS (ASCII + PLACEHOLDERS)

This section provides conceptual diagrams to support the hydrological and technical evidence presented earlier. These are illustrative only, not to scale, and intended to help the Inspector and Vale of Glamorgan officers visualise the key issues. Each diagram includes:

An ASCII sketch for immediate clarity A placeholder label for later replacement with a formal graphic in the final PDF

12.1 Diagram 1 — Catchment Overview (Placeholder: FIG-01)

Code [Higher Ground] /\ / \ / V V

Eastbrook Site (Low permeability I soils)

V [Downstream Residential Area]

Placeholder: FIG-01 - Catchment Overview Diagram

12.2 Diagram 2 - Overland Flow Routes (Placeholder: FIG-02)

Code Rainfall I V

Field <-- Overland flow entering site

V

Eastbrook Site Natural flow path I

V [Existing Properties]

Placeholder: FIG-02 - Overland Flow Route Mapping

3712.3 Diagram 3 — Groundwater Emergence Zones (Placeholder: FIG-03)

Code Subsurface Water Table

^ ^ ^ I (Groundwater emergence)

| Eastbrook Site I Saturated ground I

Placeholder: FIG-03 - Groundwater Emergence Conceptual Diagram

12.4 Diagram 4 - SuDS Limitations (Placeholder: FIG-04)

Code [Rainfall]

V [SuDS Basin]

I (Low infiltration) V [Standing Water] I V Risk of exceedance flow I V [Downstream Properties]

Placeholder: FIG-04 - SuDS Feasibility Constraints Diagram

12.5 Diagram 5 - Required Mitigation Sequence (Placeholder: FIG-05)

Code Step 1: Catchment-wide model I V Step 2: Identify mitigation I V Step 3: Secure funding & delivery

V Step 4: Construct mitigation | V Step 5: Only then permit development

Placeholder: FIG-05 - Mitigation Delivery Sequence Diagram

SECTION 13 — FORMAL REQUEST FOR WRITTEN CONFIRMATION FROM THE VALE OF GLAMORGAN COUNCIL

Given the significant unresolved constraints associated with the Eastbrook allocation, Dinas Powys Community Council formally requests written confirmation from the Vale of Glamorgan Council addressing the following matters. These confirmations are essential to demonstrate that the allocation is sound, deliverable, and compliant with national policy.

The Council requests that the Vale of Glamorgan provides a written response to each point below.

13.1 Confirmation of Catchment-Wide Modelling

Please confirm:

Whether a catchment-wide hydraulic model has been commissioned Whether NRW has been consulted on the scope Whether the model includes surface water, groundwater, and overland flow Whether the model assesses the 2020 flood event Whether the model demonstrates no increase in flood risk to existing properties

If no such model exists, please confirm:

When it will be commissioned When it will be completed Whether the RLDP will be updated to include its findings

13.2 Confirmation of Groundwater Assessment

Please confirm:

Whether a detailed groundwater assessment has been undertaken Whether groundwater emergence zones have been mapped Whether development will alter groundwater pathways Whether mitigation is technically feasible

If no assessment exists, please confirm when it will be prepared.

13.3 Confirmation of Overland Flow Route Mapping

Please confirm:

Whether high-resolution overland flow mapping has been completed Whether exceedance routes have been identified Whether these routes can be preserved within the development layout

If not, please confirm when this work will be undertaken.

13.4 Confirmation of SuDS Feasibility

Please confirm:

Whether infiltration testing has been undertaken Whether infiltration-based SuDS are viable Whether attenuation volumes have been calculated Whether SuDS can operate effectively given soil and groundwater constraints

If not, please confirm when a SuDS feasibility study will be completed.

13.5 Confirmation of Downstream Drainage Capacity

Please confirm:

Whether downstream drainage capacity has been assessed Whether upgrades are required How upgrades will be funded When upgrades will be delivered Whether upgrades will be delivered before development begins

If no assessment exists, please confirm when it will be undertaken.

13.6 Confirmation of Infrastructure Delivery

Please confirm:

How education capacity will be increased How healthcare capacity will be expanded How utilities and drainage upgrades will be funded How highways mitigation will be delivered Whether all required infrastructure is viable and deliverable within the plan period

If not, please confirm when the Infrastructure Delivery Plan will be updated.

13.7 Confirmation of Transport Assessment

Please confirm:

Whether a cumulative transport assessment has been undertaken Whether junction capacity constraints have been modelled Whether deliverable mitigation has been identified Whether sustainable transport improvements are committed and funded

If not, please confirm when this work will be completed.

13.8 Confirmation of Environmental and Landscape Evidence

Please confirm:

Whether a landscape and visual impact assessment has been prepared Whether a biodiversity net-gain strategy exists Whether a green-infrastructure plan has been completed Whether location-specific modelling to assess air quality, specifically, near schools at peak times has been undertaken.

If not, please confirm when these assessments will be undertaken.

13.9 Summary

The Vale of Glamorgan Council must provide written confirmation addressing each of the above points. Without this information, the Eastbrook allocation remains unsupported by evidence and therefore fails multiple tests of soundness.

13.10 Key objections

1. Procedural and Consultation Failures

Lack of Transparency: There is no evidence of formal record-keeping for public attendance at events or a transparent ledger showing how resident feedback was synthesized into the Plan.

Digital Barriers and Exclusion: The "online-first" strategy and complex account- creation process created a disproportionate burden for residents, particularly non-digitally native and elderly demographics who lacked accessible summaries.

Pre-determination: The requests, by DPCC, for more accessible scheduling were refused, leading to a perception that strategies were fixed prior to engaging public opinion.

When asked about the revised plans as stated in an email to DPCC we were told there were none. 2. Hydrology and Unresolved Flood Risk

The 2020 Flood Precedent: On December 23, 2020, a storm caused internal flooding to 98 properties in Dinas Powys. The Section 19 Flood Investigation Report confirmed "hydraulic locking" occurred, where elevated river levels prevented surface water systems from discharging, causing sewer surcharging.

Obsolete Evidence Base: The RLDP relies on a 2013 Strategy and a September 2020 NRW decision that predates the major 2020 flood. No catchment-wide modelling incorporating 2020 data has been undertaken.

SuDS Infeasibility: High groundwater (as shallow as 1.83m) and shallow bedrock render standard infiltration-based Sustainable Drainage Systems (SuDS) unproven and high-risk for this site.

3. Transport and Highways Constraints

Chronic Congestion: The A4055 (Cardiff Road) and Merrie Harrier junction are already at capacity. The Plan fails to assess the cumulative impact of major regional growth in Barry (376 units) and Penarth (576 units) on these local corridors.

Active Travel and Accessibility Failures: Eastbrook Station lacks bilateral access; residents with limited mobility or prams must undertake a one-mile detour to reach the Cardiff-bound platform because there is no lift.

Safety Issues: Existing pedestrian routes are too narrow for double buggies and are frequently obstructed by weekly refuse collections, forcing vulnerable pedestrians into the carriageway.

4. Exhausted Social and Utility Infrastructure

Healthcare Strain: The Dinas Powys Medical Centre is at full capacity with a list size of approximately 11,000 patients, far exceeding idealized UK GP-to- patient ratios.

Education Capacity: Local schools are operating at or near peak capacity with no identified land or funding for expansion.

Wastewater Capacity: There is no settlement-specific evidence that the consented capacity of local treatment works can accommodate 250 additional dwellings without risk of sewer surcharging.

5. Environmental and Ecological Impact

Irreplaceable Habitats: The site is adjacent to Ancient Woodland (Coed Clwyd-Gwyn and Case Hill Wood), which cannot be mitigated by new planting.

European Protected Sites: The HRA confirms the site is within 2.6km of the Severn Estuary SAC/SPA/Ramsar and explicitly concludes that "Mitigation is Required".

Air Quality: The Dinas Powys Roadside monitoring station was closed in 2016, and the Plan lacks location-specific modelling to assess the impact of increased peak-time idling near schools.

6. Housing Delivery and Demographic Misalignment Lack of Downsizing Options: Despite an aging population, the Plan contains no mandatory requirement for single-story bungalows, which are needed to free up family-sized housing stock. Affordable Housing Viability: The Community Council argues that high un- costed infrastructure burdens (flood and highway mitigation) make the 40% affordable housing target financially unviable.

S106 Transparency: £1M in S106 affordable housing funds from previous developments was diverted away from Dinas Powys because we were told there were no housing developments in Dinas Powys. Therefore the money has to be refunded or the 250 houses removed from the RLDP.

SECTION 14 — INITIAL E-MAIL FROM DPCC TO VALE OF GLAMORGAN COUNCIL (dated 29/01/2026)

The Local Development Team confirmed receipt of a formal email from Dinas Powys Community Council on 3 February 2026. This email was also sent to Senior Planning Officer, lan Robinson and CEO, Rob Thomas. It is appended below:

'Dear Sir / Madam,

Re: Formal Objection to the Proposed Allocation of Eastbrook (DNP-H1) in the Replacement Local Development Plan (RLDP)

Dinas Powys Community Council submits this formal objection to the proposed allocation of the Eastbrook site (SP4 KS2) within the Vale of Glamorgan Replacement Local Development Plan (RLDP). The Eastbrook allocation remains fundamentally flawed due to unresolved constraints relating to:

Flood risk and hydrology Highways and transport capacity Environmental and landscape impact Infrastructure limitations Deliverability and viability

The site lies within a hydrologically sensitive catchment characterised by groundwater emergence, overland flow routes, low-permeability soils, and a history of significant flood events, including the 2020 incident. Natural Resources Wales (NRW) has repeatedly raised concerns about flood risk at this location, and the Council's own evidence base acknowledges the need for catchment-wide modelling before any development can be considered.

The RLDP does not currently include:

Mandatory policy wording to secure pre-delivery of mitigation Requirements for catchment-wide modelling Guarantees that development will not increase flood risk elsewhere Evidence that mitigation is viable, deliverable, and enforceable

Without these safeguards, the allocation fails several tests of soundness, including CE2, CE3, and CE4.

Eastbrook in Dinas Powys is considered to be in a high-risk flood area. It is located within the catchment of the Cadoxton River and its tributary, the East Brook, which have a history of overflowing, causing significant, frequent flooding to homes and roads.

River and Surface Water Flooding: The area experiences flooding from the East Brook and the River Cadoxton. Intense rainfall can also overwhelm the surface water and sewerage systems, causing additional property flooding.

High Water Levels: The ground in the area, particularly in fields adjacent to existing properties, is often described as "totally waterlogged" for significant portions of the year, indicating a high- water table.

Key details regarding flood risk in this area include: High Risk Area: Natural Resources Wales (NRW) has identified a significant risk of flooding from the Cadoxton River and East Brook, affecting areas like St Cadocs Avenue, Greenfield Avenue, Elm Grove Place, and Cardiff Road.

Significant History: The area has experienced multiple flooding events, including major incidents in 1948, 1986, 1998, 1999, 2008, 2012, 2013, and a severe event in December 2020 where approximately 40-100+ properties were affected.

Future Risk: Due to climate change, the number of properties at risk of flooding in the area is expected to increase from nearly 200 to over 350 by 2117.

Causes: The area suffers from rapid runoff from the surrounding hillsides, which overwhelms the capacity of the river channels and drains. NRW has been exploring options for a flood management scheme, including natural flood management and potential engineering solutions, to reduce the risk to the community. It is recommended to check the specific, up-to-date flood map for any particular property on the NRW website.

The Dinas Powys Community Council formally requests written confirmation from the Vale of Glamorgan Council addressing the following matters:

1. Has a catchment-wide hydraulic model has been commissioned, completed, and agreed with NRW? If so, does the model demonstrate no increase in flood risk to existing properties? 2. Have groundwater emergence, overland flow routes, and the 2020 flood event have been assessed? 3. Are SuDS viable given soil and groundwater constraints? 4. Has downstream drainage capacity been assessed and, if necessary, upgraded? 5. Will education, healthcare, utilities, and highways infrastructure be expanded to support the allocation? a) Has consultation taken place with the GP surgery/Local schools? b) What additional services will be provided? 6. Have deliverable and funded mitigation for transport and highways impacts been identified? a) Please provide figures of air pollution and traffic flow surveys along Cardiff Road. What is the capacity along Cardiff Road? b) Department of transport will not be investing in Eastbrook station. Therefore, no lift/ramp to address the needs of the community. Yet it is being used to form a decision about the housing. Please explain the reason behind this?

7. Have landscape, biodiversity, and green-infrastructure assessments been completed? a) Apparently the placemaking workshop has helped refine proposals. What are the refinements and when can we see the results from the surveys people completed at the Murchfield consultation?

In the opinion of Dinas Powys Community Council these confirmations are essential to demonstrate that the allocation is sound and that development will not increase flood risk or place unacceptable pressure on local infrastructure.

The Vale Council state that millions of pounds of Dinas Powys S106 funding could be moved to Myrtle Close in Penarth as 'there are no developments' in Dinas Powys. If this is the case Eastbrook needs to be removed from the RLDP or the money should stay allocated to Dinas Powys.

The Vale Council allocated 900-1500 houses for Argae lane. But once the site was considered not viable the figures were reviewed and they were reduced in number and moved to another site.

Where is the evidence that 250 houses are needed in Eastbrook? The Eastbrook site was turned down before. Why? What has changed to make it viable now? Have the Vale Council exhausted all the key sites outlined in the previous LDP and if not why? Have the Vale Council used all of their rolled forward housing sites? Have the Vale Council carried out a Sequential Test? Proving there are no lower risk sites available? Has the Exception test been carried out? Ensuring the development will be made safe throughout its lifetime without increasing floor risks elsewhere? Out of the 250 houses 40% will be affordable housing. Managed by housing associations according to Persimmon glossy proposal. What is classed as affordable housing? Birth rate has fallen for a number of years, and the elderly population is increasing. How do you justify these figures? What proportion of the proposed 250 houses will be age friendly?

In the appendix to the Homes and Safe Communities Scrutiny Committee report (6th January 2024), there is a comment regarding the need for bungalows. Residents and councillors enquired about bungalows enabling people to downsize and free up family homes. We were told they are providing what the Vale has requested. We met with housing and they said, 'it won't happen'. So knowing there is a need for elderly accommodation what is the plan to address this need?

By 2034, 1 in 4 will be over the age of 65. This is an increase of 75% from 9.3% in 2018 to 13.7% in 2038.

The Vale indicates 70% of the housing need is in Barry/Penarth and Llandough. Of the remaining 30% what percentage is allocated to Dinas Powys? You state greatest areas of demand are Penarth/Barry and Llandough but there is no mention of Dinas Powys.

In conclusion, in the absence of the required evidence and mandatory policy safeguards, the Eastbrook allocation remains unsound. The Dinas Powys Community Council therefore requests that the Vale of Glamorgan Council: Removes the Eastbrook allocation from the RLDP, or Incorporates the mandatory policy wording and evidence requirements set out above. We look forward to receiving your written response. Yours faithfully, Clerk on behalf of Dinas Powys Community Council'

SECTION 15 — CONCLUSION OF THE

TECHNICAL OBJECTION

Dinas Powys Community Council recognises the importance of delivering sustainable, well-planned growth across the Vale of Glamorgan. The revised RLDP contains some positive and constructive changes, and the Council welcomes the improved emphasis on sustainability, climate resilience, and infrastructure capacity. However, despite these improvements, the proposed allocation of the Eastbrook site (HG1 - KS2) remains fundamentally unsound.

The evidence presented in this objection demonstrates that:

The site lies within a highly sensitive hydrological catchment Flood risk is influenced by surface water, groundwater, and overland flow The 2020 flood event provides clear evidence of the site's vulnerability NRW has repeatedly raised concerns that have not been resolved No catchment-wide hydraulic modelling has been undertaken SuDS feasibility is unproven due to soil and groundwater constraints Downstream drainage capacity has not been assessed Transport and highways impacts remain unmitigated Education, healthcare, and utilities infrastructure are already under pressure No evidence demonstrates that required mitigation is viable, fundable, or deliverable The RLDP lacks mandatory policy wording needed to secure mitigation and ensure no increase in flood risk elsewhere

As a result, the allocation fails multiple tests of soundness, including:

CE2 - Coherence and effectiveness CE3 - Environmental protection CE4 - Deliverability

Until the Vale of Glamorgan Council provides the required evidence and incorporates the mandatory policy wording set out in this document, the Eastbrook allocation cannot be considered sound. The Dinas Powys Community Council therefore respectfully requests that the Vale of Glamorgan Council:

1. Removes the Eastbrook allocation from the RLDP, or 2. Incorporates the mandatory policy wording, evidence requirements, and safeguards detailed in this objection

Failure to address these issues will leave the RLDP vulnerable to challenge at Examination and may result in development that increases flood risk to existing residents, places unacceptable pressure on local infrastructure, and undermines the environmental quality of Dinas Powys.

Dinas Powys Community Council remains committed to constructive engagement and looks forward to receiving the Vale of Glamorgan Council's written response to the matters raised.