Environmental Assessment
Introduction
This section draws on the A75 Springholm and Crocketford DMRB Stage 1 Environmental Appraisal Report (EAR). The purpose of the EAR was to inform decision makers and designers on the environmental constraints and potential impacts associated with the six improvement strategies being considered at DMRB Stage 1.
Approach to Environmental Assessment
Previous Environmental Assessment
As discussed in the introduction, the A75 Trunk Road was considered as part of ‘Recommendation 40’ of STPR2 , which focused on improving access to the Loch Ryan port facilities (Cairnryan). All STPR2 recommendations were assessed in the STPR2 Strategic Environmental Assessment (SEA). The STPR2 SEA Environmental Report was publicly consulted on alongside the STPR2 Final Technical Report between December 2022 and February 2023.
The A75 Trunk Road was also included in the SWestrans Regional Transport Strategy (RTS) under the following themes that were included in the RTS and assessed in the RTS SEA:
- Theme 4: Reducing the Impact of Transport on Our Communities. Priority i: Investigate the feasibility of bypasses for Crocketford and Springholm on the A75 as well as other communities on the A7, A75, A76, A77 and A709 including Dumfries.
- Theme 8: Supporting Safe, Effective and Resilient Connections to Loch Ryan and Other Strategic Sites. Priority ii) Enhancements to the strategic road network including the A7, A75, A76, A77 and A709 should be taken forward to improve safety, journey times, diversionary routes and improve access to key locations across the region.
The RTS SEA Environmental Report was published in Autumn 2022 for a 12 week consultation period. The RTS SEA Post Adoption Statement was published in June 2024.
Methodology
The STPR2 SEA and the SWestrans RTS SEA described in the section above are high level, with little data specific to the A75 Trunk Road. It was therefore agreed that an EAR should be produced, specific to the A75 Springholm and Crocketford Improvements at DMRB Stage 1 to enable a more informed understanding of the environmental sensitivities in proximity to the proposed scheme.
All environmental factors (for example noise and air quality) have been scoped in for assessment at DMRB Stage 1. An outline of the methodologies for each factor are reported within the EAR. These factors are aligned with DMRB LA 101 - Introduction to environmental assessment (revision 0) , DMRB LA 103 - Scoping projects for environmental assessment (revision 1) , and DMRB LA 104 - Environmental assessment and monitoring (revision 1) . The EAR also follows guidance from DMRB TD 37/93 - Scheme Assessment Reporting .
The EAR describes baseline conditions, assessment methodologies, potential impacts, design, mitigation and potential enhancement measures, and provides a preliminary assessment of likely significant effects.
The EAR includes an appraisal for the following environmental factors:
- Air Quality
- Cultural Heritage
- Landscape and Visual
- Biodiversity
- Geology, Soils and Groundwater
- Material Assets and Waste
- Noise and Vibration
- Population and Human Health
- Road Drainage and the Water Environment
- Climate
- Cumulative Effects
For DMRB Stage 1, a high level, primarily desktop review approach was used for all environmental factors.
Findings
This section presents the findings from the EAR, detailing the key impacts of the identified improvement strategies on each of the environmental factors outlined in the previous section.
For the purpose of this environmental assessment, and to ensure a ‘worst case’ approach, the full improvement strategy width of 200 meters has been considered. However, on selection of improvement strategies to take forward to DMRB Stage 2 for route option development, it is recognised that some of the impacts identified could be avoided or reduced as the route options will likely not have a width of 200 metres, for example direct impacts on listed buildings, Milton Loch Site of Special Scientific Interest. This will be acknowledged when undertaking the comparative assessment.
Air Quality
It is unlikely there will be exceedances of Air Quality Objectives (AQO) or Limit Values (LV) for human receptors, however, there is potential for significant effects at designated sites (for example ancient woodland) within 200m of the affected road network (ARN). Therefore, a simple DMRB assessment, based on DMRB LA 105 Air Quality (vertical barriers) (revision 0.1.0) , should be undertaken at DMRB Stage 2 to assess the operational opening year impacts at designated sites within 200m of the ARN. A small number of human receptors close to the improvement strategies could also be assessed for illustrative purposes using a simple approach to show that concentrations at human health receptors will be significantly below the AQOs/LVs. It is proposed that a construction assessment is not undertaken until DMRB Stage 3.
Cultural Heritage
Table 5‑1 shows the heritage assets that have potential to experience likely significant effects during construction of the proposed scheme. The table also shows a comparison of the numbers of heritage assets within each improvement strategy. At DMRB Stage 2, the location of these heritage assets will be taken into consideration during design development with the aim of avoiding or reducing impacts.
| Likely Significant Adverse Effects | Improve-ment Strategy 1 | Improve-ment Strategy 2 | Improve-ment Strategy 3 | Improve-ment Strategy 4 | Improve-ment Strategy 5 | Improve-ment Strategy 6 |
|---|---|---|---|---|---|---|
|
Number of Category B Listed Buildings potentially impacted |
3 |
2 |
7 |
4 |
0 |
1 |
|
Number of non-designated Historic Buildings potentially impacted |
2 |
0 |
9 |
1 |
4 |
2 |
|
Number of non-designated Archaeological Sites potentially impacted |
1 |
6 |
2 |
2 |
3 |
3 |
At this stage, no significant impacts are anticipated during construction or operation to the Conservation Area or Scheduled Monuments.
Cultural Heritage assets are considered to be an irreplaceable resource and as stated in DMRB LA 106 - Cultural Heritage Assessment , the ‘need for development’ should be balanced against the requirement to ’protect and enhance our national cultural heritage resource’ in line with national and local legislation, policy and good practice guidance.
Landscape and Visual
All six improvement strategies have been assessed with regards to their potential impacts on landscape and visual receptors. Each improvement strategy presents differing levels of potential impact to landscape and visual receptors. All improvement strategies would result in changes to the rural landscape character and views from residential properties, active travel routes, local roads and other locations within the surrounding landscape.
Improvement Strategy 3 would be likely to have the least adverse effects on the rural landscape and least visual effects on scattered rural properties of all the improvement strategies but the most significant effects on the townscape and visual receptors along the existing A75 within Springholm and Crocketford. Of the remaining (offline) improvement strategies, Improvement Strategy 4 would be likely to have the least adverse landscape and visual effects, followed by Improvement Strategies 2 and 5, then Improvement Strategy 1 and Improvement Strategy 6 likely to have the greatest adverse effects. Further details on the landscape and visual effects of each improvement strategy are summarised as follows.
Improvement Strategy 1
Improvement Strategy 1 would be likely to have a significant adverse effect on both landscape and visual receptors. Significant effects would result from permanent changes to the landform and pattern on high ground with several hills and surrounding topography permanently altered, impacts on the landscape pattern, severance and loss of woodland (including Ancient Woodland Inventory (AWI)), habitat corridors, green networks (including along Urr Water and various minor watercourses) and boundary features including drystone walls together with the introduction of the new road infrastructure and traffic into the rural landscape. This improvement strategy would result in loss and severance of AWI woodlands and likely impacts on undulating landform north of Auchenreoch Loch. There is also potential for indirect effects (on views) of this option from Terregles Local Landscape Character Area (LLA). The length of the improvement strategy, its partly elevated position in the landscape and proximity to settlements including Brae, Kirkpatrick Durham, Old Bridge of Urr, Clarebrand, Crocketford and numerous individual properties to the north of the existing A75 would be likely to result in significant visual effects. The rural setting north of Auchenreoch Loch would be affected, with the visual receptors at The Inn on the Loch impacted, though there would be benefits on the south side of the loch from reduced traffic on the existing A75. This improvement strategy would result in beneficial landscape and visual effects along the existing A75 route including improved townscape and visual amenity within Springholm and Crocketford.
Improvement Strategy 2
Improvement Strategy 2 would be likely to have a significant adverse effect on both landscape and visual receptors. Significant effects would result from permanent changes to the landform and pattern on high ground with several hills and surrounding topography permanently altered, impacts on the landscape pattern, severance and loss of woodland (including AWI), habitat corridors, green networks and boundary features. The central section of this improvement strategy, which follows the same route as Improvement Strategy 1, would result in loss and severance of AWI woodlands and likely impacts on undulating landform north of Auchenreoch Loch. Residents of Kirkpatrick Durham, Brae and north facing properties in Crocketford and rural properties would be likely to experience adverse visual effects. The rural landscape north of Auchenreoch Loch would be affected, with the visual receptors at The Inn on the Loch impacted, though there would be benefits on the south side of the loch from reduced traffic on the existing A75. This improvement strategy would result in beneficial landscape and visual effects along the existing A75 route including improved townscape and visual amenity within Springholm and Crocketford.
Improvement Strategy 3
Improvement Strategy 3 is online and would therefore result in the least adverse effects on the rural landscape and visual effects on rural properties but would have significant adverse effects on the townscape and visual amenity within Springholm and Crocketford. Visual effects on residents, workers and visitors in the two villages during construction are likely to be significant, as a result of widening and potential demolition of properties along the existing A75. During operation, visual effects are likely to be significantly worse than those currently experienced, due to road widening and removal of existing screening features, including buildings which currently screen the existing A75 from neighbouring areas, particularly as space for mitigation measures would be limited.
Improvement Strategy 4
Improvement Strategy 4 is considerably shorter than Improvement Strategies 1, 2, 5 and 6 and closer to the existing A75. This improvement strategy, which follows the lower valley slopes and valley floor avoiding hills and AWI woodland, and severing a relatively small number of field boundary features/green corridors would have less significant adverse landscape effects than Improvement Strategies 1, 2, 5 and 6, while providing improved townscape and visual amenity in the bypassed settlements of Springholm and Crocketford. However, it would potentially affect the landscape setting of a group of listed buildings at Newbank Mill. The reduction/removal of traffic on the existing A75 alongside Auchenreoch Loch would slightly improve the landscape setting of the loch and enhance visual amenity. There is the potential for significant effects on rural views currently experienced from residential properties in Springholm, Crocketford and Brandedleys Holiday Park.
Improvement Strategy 5
Improvement Strategy 5 is considered likely to have broadly similar overall levels of landscape and visual effects to Improvement Strategy 2, but with the most significant landscape and visual effects likely to result from the route crossing high ground of Barfil Hill, Cairny Hill, Longshot Hill and the northern slopes of Tan Hill. This improvement strategy would also result in changes to the landscape pattern and severance and loss of woodland, habitat corridors, green networks and boundary features. Visual receptors in Springholm, Crocketford and Hardgate as well as rural properties would likely be affected by views of this improvement strategy. The reduction/removal of traffic on the existing A75 alongside Auchenreoch Loch would improve the landscape setting of the loch and enhance visual amenity. This improvement strategy would result in beneficial landscape and visual effects along the existing A75 route including improved townscape and visual amenity within Springholm and Crocketford.
Improvement Strategy 6
Improvement Strategy 6 is the second longest and would likely have the most significant adverse effect to landscape and visual receptors south of the existing A75. Significant effects would result from permanent changes to the landform on high ground including several hills, impacts on the landscape pattern, severance and loss of woodland (including native woodlands), habitat corridors and green networks (including along Urr Water and various minor watercourses) together with the introduction of the new road infrastructure and traffic into the rural landscape. There is also potential for indirect effects (on views) of this improvement strategy from Terregles Local Landscape Character Area (LLA). The length of the improvement strategy, its elevated position in the landscape and its proximity to numerous individual properties and several settlements, most notably Hardgate and Haugh of Urr, would be likely to result in significant visual effects. Parts of this improvement strategy run close to National Cycle Network (NCN) 7 so would likely have adverse visual effects on cyclists. This improvement strategy would result in beneficial landscape and visual effects along the existing A75 route resulting from reductions in traffic, including improved townscape and visual amenity within Springholm and Crocketford.
Biodiversity
A high level assessment of the improvement strategies in relation to biodiversity was undertaken. The proposed scheme, regardless of the improvement strategies selected, is likely to result in some adverse effects to biodiversity at a local level in relation to habitat loss and fragmentation, and the associated effects on notable and protected species.
Improvement Strategies 1 and 6 would likely have the greatest impact on biodiversity in general as they cover the greatest total area and both will involve construction of a river crossing over Urr Water, resulting in a greater potential impact on aquatic habitats and species. Improvement Strategy 1 is also likely to result in a greater loss of AWI which is considered to be irreplaceable habitat, compared to other improvement strategies.
Improvement Strategy 5 would also involve construction of a river crossing over Urr Water. In addition, Improvement Strategy 5 lies partially within Milton Loch Site of Special Scientific Interest (SSSI), therefore, construction and operation of the proposed scheme may directly and indirectly impact the SSSI. Improvement Strategy 5 also covers the largest area of woodland recorded in the Native Woodland Survey of Scotland (NWSS) of all improvement strategies.
As all six improvement strategies are in relatively close proximity to each other, the protected and notable species present are likely to be similar across all improvement strategies, provided habitat across the improvement strategies is similar. The proposed scheme may provide minor beneficial effects to biodiversity if habitat enhancement is employed beyond the level required for mitigation. Field surveys will be required at DMRB Stage 2 to provide further information on the habitats and species likely to be impacted by the proposed scheme.
Geology, Soils and Groundwater
A range of baseline data has been reviewed and used to identify relevant geology, soils and groundwater receptors. The receptors identified for the improvement strategies are agricultural soils, human health, groundwater and surface waters.
In accordance with relevant industry guidance, an assessment was undertaken on the potential effects on these receptors from the implementation of the proposed scheme and their potential significance. The following significant effects were identified for all improvement strategies unless otherwise stated:
- Physical removal or permanent sealing of agricultural land and/or peat.
- Reduction or loss of soil function(s) due to stripping, handling and storage, through mechanisms such as compaction or erosion.
- Potential mobilisation of contamination and/or surface water runoff into Milton Loch SSSI (Improvement Strategy 5 only).
- Spills and leaks of construction runoff could impact groundwater quality.
- Routine road runoff discharge or spills and leaks increase the risk of pollution.
In conclusion, potential significant effects were similarly identified across all improvement strategies. With the exception of Improvement Strategy 5 where additional potential significant effects were identified for surface water due to its proximity to Milton Loch SSSI.
The risk of potential significant effects being realised is highest for Improvement Strategies 1 and 6 as they cover the greatest total area. Improvement Strategy 5 is the next most likely to have significant effects due to its length and proximity to Milton Loch SSSI, followed by Improvement Strategy 2, then Improvement Strategy 4 and 3 due to their smaller total areas.
The identified effects on soils are due to land take and would need to be mitigated through route optioneering or future design mitigation measures.
Material Assets and Waste
At this stage, all improvement strategies have been assessed to have similar significance for adverse effects. All improvement strategies are likely to have moderate and significant effects on regional and Scotland-wide waste receptors and are likely to have large and significant effects on regional material asset and mineral safeguarding area receptors.
As is proportionate at DMRB Stage 1, estimated quantities for materials required and waste generated from the proposed scheme have not been taken into consideration. Assumptions have been made based on approximate improvement strategy lengths and indicative maximum number of new major structures required. Table 5‑2 summarises the outcome of this assessment, using a ranking from 1 st (likely to have the most significant effect) to 6 th (likely to have the least significant effect).
| Improvement Strategy | Likely Significance of Effect of Material Assets and Waste (Ranked in Order From Most to Least) |
|---|---|
|
Improvement Strategy 1 |
1st |
|
Improvement Strategy 6 |
2nd |
|
Improvement Strategy 2 |
3rd |
|
Improvement Strategy 5 |
4th |
|
Improvement Strategy 4 |
5th |
|
Improvement Strategy 3 |
6th |
However, due to the high level nature of information available at this stage, Table 5‑2 does not account for the potential effects of demolition waste as a result of the proposed scheme. This will need to be assessed in further stages of assessment in order to gain clarity on the effects of construction, excavation and demolition waste generated by the proposed scheme.
Noise and Vibration
It is likely that the construction phase would result in some temporary significant adverse effects for some noise sensitive receptors close to the construction works for any of the improvement strategies. Significant adverse effects can usually be mitigated through the implementation of a Construction Environmental Mitigation Plan (CEMP). Construction phase impacts and effects will be considered in more detail at DMRB Stage 2 and 3.
The operation phase would result in changes in road traffic noise for noise sensitive receptors, depending on their location relative to the proposed scheme. The overall effects are likely to be similar whichever improvement strategy is selected, although Improvement Strategy 3 is less likely to result in any significant beneficial effects. Operational phase impacts and effects will be considered in more detail at DMRB Stage 2 and 3.
Population and Human Health
The population and human health assessment focuses on land take, accessibility and health impacts on communities and receptors. All improvement strategies potentially involve land take that could impact on residential, agricultural, commercial and community receptors and could result in likely significant effects. Improvement Strategy 3, which largely involves online improvements, could result in likely significant effects for receptors adjacent to the road, arising from construction activities and operational traffic, but could involve less total land take than the other improvement strategies. The improvement strategies that involve creation of offline road space (1, 2, 4, 5, and 6) may have fewer accessibility impacts for communities through construction and operation as the existing road infrastructure could be utilised; however, community severance could be an issue.
For human health, all improvement strategies have the potential to result in a change to health determinants related to air quality, noise, pollution, landscape amenity and severance/accessibility. Construction traffic and activities have the potential to increase dust and noise and vibration and result in temporary disruption in access to facilities relied upon for health (for example medical facilities). During operation, an increase in traffic could result in an increase in air and noise pollution, which could particularly impact on vulnerable populations (for example children and the elderly). Land take could result in permanent changes in access to community assets relied upon for physical activity and social cohesion (for example green/open space). Outputs of the relevant environmental assessments have been considered and at this stage, it is concluded that it is not possible to differentiate between improvement strategies in terms of likely significant effects on health outcomes. It is noted that likely significant effects are dependent on design and mitigation that is yet to be determined.
Road Drainage and the Water Environment (RDWE)
The RDWE assessment reviewed a range of baseline data to identify relevant surface water, hydromorphology and flood risk receptors. The assessment was undertaken in accordance with relevant industry guidance to identify the potential effects on these receptors and their significance from the implementation of the proposed scheme. Table 5‑3 shows the potential significant effects identified (pre-mitigation) for the sub-elements of the RDWE assessment.
All sub-elements of the RDWE DMRB Stage 1 Assessment have been scoped in for both the construction and operation phases, and will be assessed as part of DMRB Stage 2. Surface water supply has not been assessed due to the high level information available at this stage in the process. This sub-element has been retained for full assessment at a later stage.
| Sub-element | Effect Identified (Construction Phase) | Effect Identified (Operational Phase) | Improvement Strategy | Potential Significance of Effect (pre-mitigation) (Construction and Operational phases) |
|---|---|---|---|---|
|
Surface water quality |
Release of fine sediments and pollutants from construction runoff and other construction activities (for example use and fuelling of plant, runoff from stockpiles and stripped land). |
Polluted runoff/accidental spillages from new road surfaces entering the road drainage system and entering into watercourses. |
All improvement strategies |
Large or Very Large |
|
Hydromorphology |
Temporary alterations to the bed and banks of watercourses and release of sediment during construction with the potential to alter morphological features, sediment dynamics and flow dynamics. |
Operation of culverts, bridges and outfalls, representing changes to the morphological condition, sediment dynamics and flow dynamics of the watercourse. |
|
|
|
Flood risk |
Temporary decreases in floodplain storage and displacement of flood water. |
Decrease in floodplain storage and displacement of flood water. |
All improvement strategies |
To be determined at later design stage |
|
Flood risk |
Compaction of land to create level surfaces leading to changes in infiltration rates and increased runoff rates. |
Increases in runoff rates due to increases in impermeable areas. |
All improvement strategies |
To be determined at later design stage |
|
Flood risk |
Alteration of below ground level flows potentially leading to groundwater flooding elsewhere. |
Alteration of below ground level flows potentially leading to groundwater flooding elsewhere. |
All improvement strategies |
To be determined at later design stage |
|
Flood risk |
Potential for in-channel works in areas of flood risk |
Alteration of below ground level flows potentially leading to groundwater flooding elsewhere. |
All improvement strategies |
To be determined at later design stage |
The identified effects on RDWE as presented in Table 5-3 are those considered without mitigation. Some of these effects would be mitigated using the measures outlined in the Road Drainage and the Water Environment Chapter of this EAR. At later design stages, as more detailed design information becomes available, additional mitigation measures, including embedded mitigation, may be required to reduce any potential effect as far as reasonably practicable.
Climate
A high level qualitative assessment of the improvement strategies has been undertaken at DMRB Stage 1 as summarised in Table 5‑4. This is due to limited design and traffic data which is a common constraint at this early stage of the process. Improvement Strategy 1 is entirely offline, crosses Urr Water and would likely require the most new major structures. It is therefore likely to require more construction works (and would likely result in higher construction GHG emissions) than the other improvement strategies. Improvement Strategy 3, which is online, would not require as many new major structures to be constructed as most other improvement strategies and is likely to result in the least construction and associated GHG emissions.
Due to the broadly defined nature of the improvement strategies, the numbers of retaining walls, culverts and minor bridges (expected length of less than 20m) have not been included in Table 5-4. Minor structures will be assessed at DMRB Stage 2.
|
Improvement Strategy |
Approximate Length (km) |
Crosses Urr Water |
Indicative Number of New Major Structures |
|
Improvement Strategy 1 |
19.0 |
Yes |
4 |
|
Improvement Strategy 2 |
12.4 |
No |
2 |
|
Improvement Strategy 3 |
5.4 |
No |
1 |
|
Improvement Strategy 4 |
6.0 |
No |
2 |
|
Improvement Strategy 5 |
11.0 |
Yes |
1 |
|
Improvement Strategy 6 |
17.2 |
Yes |
3 |
The likely receptors related to the proposed scheme’s vulnerability to climate change were identified in the Climate chapter of the EAR along with their vulnerable elements and the likely impacts for the relevant climate events. The types of receptors are not expected to differ considerably between the improvement strategies as many of the receptor types are common to them all, with the exception of those with major water crossings (for example bridges).
As all six improvement strategies are in relatively close proximity to each other, the climate conditions currently, or projected to be, experienced in the study area are considered to be the same for each improvement strategy. Therefore, in terms of direct exposure to adverse weather conditions, all the receptors, regardless of the improvement strategy, are considered to be at a similar risk, with the exception of those with major water crossing (for example bridges), which would be at a higher risk. Therefore, at DMRB Stage 2 further work is required to inform the selection process for a preferred route option.
Cumulative Effects
The cumulative effect assessment identified that the following receptors may be subject to combined effects:
- Residents in close proximity to the improvement strategies.
- Users of community facilities.
- Public open spaces.
- Public Rights of Way (PRoW).
- Agricultural land holdings.
- Peatland.
There have been no major developments identified that would contribute to cumulative effects. Land allocated for development by Dumfries and Galloway Council through the Local Development Plan (LDP2) was recorded within 2km of the improvement strategies. All 11 of the allocations are situated within the 2km of Improvement Strategies 1 and 6. This means that Improvement Strategy 1 and 6 are likely to have the largest potential for cumulative effect on the surrounding area, given the number of allocations. The list of developments and allocations will be reviewed at DMRB Stage 2.
Summary
Of all the environmental factors included as part of the EAR, only Air Quality concluded at this stage that the proposed scheme is likely to have no significant effects.
The following environmental factors reported the potential for likely significant (adverse) environmental effects:
- Landscape and Visual - changes to the rural landscape character and views from residential properties, active travel routes, local roads and other locations within the surrounding landscape.
- Biodiversity - habitat loss and fragmentation and loss of protected species.
- Geology, Soils and Groundwater–disturbance and runoff of contaminants, loss of agricultural land and or peat, reduction or loss of soil function(s), groundwater contamination and impacts to groundwater levels.
- Material Assets and Waste–potential impacts to regional material assets and mineral safeguarding area receptors.
- Noise and Vibration–temporary construction noise may impact sensitive receptors in the surrounding area.
- Road Drainage and Water Environment–potential for likely significant effects was reported in relation to surface water quality, hydromorphology and flood risk.
- Climate–Increase in GHG emissions dependent on improvement strategy selected and the vulnerability of the proposed scheme to climate change as all improvement strategies will be impacted equally by extreme weather conditions.
The potential effects identified are based on a worst case, high level, desktop review. It is expected that through design development and implementation of mitigation measures at subsequent DMRB stages that the scale and significance of effects could be reduced.