Conclusions

The A9 P2 NCA explored the effects of the proposed scheme on ecosystem service benefits as a result of its impacts on natural assets (habitats) within the NCA boundary.

The key changes to natural capital assets as a result of the proposed scheme are the losses of woodland habitat totalling to 12.7ha within the NCA boundary. Whilst there is a gain of 14.9ha of deciduous woodland types, there is a loss of 27.7ha of coniferous woodlands, resulting in an overall deficit within the NCA boundary. In contrast, there a notable increase in the area of other neutral grassland. Other notable impacts were a loss of 65% of bracken habitat and the majority of arable habitat within the NCA boundary.

The impact on eleven ecosystem service benefits was assessed in qualitative terms. Adverse impacts are assumed for food production, timber production, air pollutant removal, carbon reduction and flood regulation. Carbon reduction impacts are deemed to be the most substantial, primarily due the loss of soil and vegetation carbon stocks associated with woodland clearance. Pollination and recreation benefits are forecast to increase from the proposed scheme. Recreation benefits are deemed to be substantial, associated with new footpath creation and enhancement measures which are assumed to improve access, to and recreational experience from the use of, multiple greenspace sites. There could also be notable benefits from education and volunteering; however these are identified as opportunities which could be realised through additional scheme enhancements.

Six ecosystem service benefits (excluding education and volunteering opportunities) were assessed in monetary terms (and a number of these presented with supporting quantitative [biophysical] evidence). In alignment with the qualitative assessment, the impacts on carbon reduction and recreation had the most notable effects on total NPV for the proposed scheme. Over 100 years the NPV (for the optimism scenario) is forecast to range from -£15.73m to (+)£222.58k . Over 60 years, the NPV is between -£16.03m to -£820.8k. Over 100 years, the overall benefits are greater due to the fact that the bulk of losses associated with carbon reduction occur early in the proposed scheme lifecycle and thus over time, some of these losses are offset by the recreation benefits.

If volunteering and education opportunities are delivered upon, the 100-year NPV for proposed scheme would range from -£15.32m to (+)£1.62m. Over 60 years, the NPV would range from -£15.7m to (+)£328.41k.

It is also important to note that the impacts to ecosystem services presented in this NCA are potentially underestimated in the case of benefits or overestimated in the case of disbenefits. This is due to the fact that offsite enhancements and woodland compensation measures (which have not yet been confirmed) have not currently been included within the SBMT, the outputs from which underpin this assessment. It would be recommended that this NCA is updated once this information is available.

The NCA has identified a number of risks and opportunities for the proposed scheme with regards to ecosystem service benefits. These have been summarised in Table 7‑1.

Risks and opportunities

Table 7‑1: Natural capital risks and opportunities
Ecosystem service	Risks	Opportunities
Food production	The proposed scheme is anticipated to result in the loss of some agricultural areas, most notably around 6ha of arable land with a corresponding reduction in to agricultural output anticipated.	NA – small loss of agricultural land associated with the proposed scheme. Limited, tangible opportunities identified.
Timber production	The proposed scheme is anticipated to negatively impact timber production, due to an expected loss of a site currently with an active felling licence. However, the extent of this impact is currently uncertain, as it is not currently confirmed how much of this area will be required for mitigation planting.	If the whole area currently planned for mitigation planting is not required, there may be opportunities for timber production to continue. However, the scheme is unlikely to present any opportunities to positively impact timber production directly.
Air pollutant removal	The proposed scheme is expected to lead to initial habitat loss, impacting air pollutant removal. While the proposed scheme will create woodland and grassland habitat, the benefits will take time to materialise, as newly planted areas must mature before reaching optimal conditions.	Strategic implementation of compensatory woodland planting and new habitat creation as part of biodiversity enhancement efforts could maximise air pollutant removal effectiveness. Albeit, potential benefits are limited by limited background air pollution.
Carbon reduction	The loss of woodland habitat due to scheme land take presents a clear risk in terms of the loss of future nature-based carbon removals. Failure to consider the carbon implications of mitigation and/or compensation efforts could result in additional carbon losses. For example, the enhancement of existing woodland parcels over and above new woodland creation could mean significantly less carbon offsetting potential.	Compensatory planting of new woodland parcels presents the opportunity to offset a degree of the forecasted carbon losses as a result the overall habitat losses due to the proposed scheme land take. The composition and structure of woodland planting proposals could be considered to optimise the potential carbon offsetting opportunities.
Flood regulation	The proposed scheme is anticipated to result in a loss of woodland habitat which could play a role in slowing overland flows and floodwater storage, particularly important given the steep topography of the surrounding area and the fact that notable areas of Inver, Little Dunkeld and Birnam are subject to regular flooding from the River Tay and River Braan.	Compensatory woodland planting and new habitat creation as part of biodiversity enhancement efforts could be carried out strategically to integrate and/or deliver Nature-Based Solutions (NBS) to reduce downstream flood risk.
Pollination	There was very limited citizen science data on pollinator/host species available across the study area. This may have a resulted in the high value of some habitat areas being under-represented (i.e., showing as only moderate value to pollinators, rather than high). Despite this, impacts of the proposed scheme are still anticipated to be represented by this methodology. There is a risk the construction of the proposed scheme will disrupt pollinator species. However, overall, there is likely to be a generally positive impact as a result of the mitigation planting.	Undertake pollinator surveys or more detailed assessments of pollination to determine the impacts of the scheme. There is an opportunity for the proposed scheme to include measures to further support pollinators through the re-planting of vegetation.
Soil erosion protection	The proposed scheme is expected to have an overall minimal impact on soil erosion protection; however, this is primarily due to the mitigation measures to be put in place such as replacement habitat creation alongside good design and practice measures.	Geotechnical risks arising from soil erosion are being considered and mitigated against. Options could be reviewed strategically to integrate and/or deliver NBS to reduce the negative effects of soil erosion.
Education	NA – no risk identified to education benefits, provided by the natural environment, associated with the proposed scheme.	This assessment has identified a number of cuttings which could expose geological features comparable to those localities which make Dunkeld and Little Glen Shee a destination excursion for universities, geological societies and geology enthusiasts. Only relatively small enhancements would be required to make any exposed features accessible, adding to the geological heritage in the area enjoyed by these communities.
Landscape and amenity	The proposed scheme is expected to have an overall minimal impact to landscape; however, this is primarily due to the mitigation measures to be put in place. If these were not to be delivered, these is likely to be more negative impacts to the surrounding landscape.	The mitigation planting required for the scheme is likely to have positive impacts for the surrounding landscape and perception of landscape.
Recreation	The assessment of recreation benefits considered only residual (post mitigation) impacts. Without the mitigation detailed in the DMRB Stage 3 Population – Accessibility chapter which supports mitigation of impacts on the amenity of footpaths, and enhancements to existing footpaths, the results could be less favourable.	The proposed path connecting River Wood and Path 15 within the Dalpowie Plantation presents substantial potential for recreation benefit by creating a cohesive and accessible riverside route for WCH users by connecting the Ring Wood Area to the Murthly Riverside Path via Dalpowie. If a formal connection is created, this could greatly improve the River Tay Way route, negating the need for its diversion south of the A9 (away from the riverside) to reach Dunkeld from the Murthly Estate. The River Braan OAA (Inver) area has a high footfall and the new, circular route and planned footpath enhancements could add significant value. Currently, Path 35 is an informal, narrow and unbound track with relatively poor accessibility. Improving accessibility for a wider array of users could add substantial benefit.
Volunteering	Not Applicable – no risk identified to volunteering opportunities, presented by the natural environment, associated with the proposed scheme.	The proposed scheme could enhance volunteering opportunities for local environmental groups, expanding their outreach and positive impact. Such initiatives offer numerous personal and social benefits, such as physical activity, social engagement and skill development while also providing valuable insights into the local ecology.

Recommendations

This NCA has been authored to align with the DMRB Stage 3 EIAR and should be considered supplementary to the EIAR findings. The findings herein should hence be considered in the decision-making processes relevant to the EIAR. Additionally, there is an opportunity to include the benefits quantified, particularly the monetary ecosystem service outcomes, within the business case for the proposed scheme. It is worth noting that the outcomes of the NCA were based on proposed scheme design for the DMRB Stage 3 Design Fix, at which stage opportunities for further voluntary habitat enhancements within land adjacent to the proposed scheme were still being discussed. Further consultation will be undertaken to identify additional off-site areas for enhancement as required. It is recommended that the NCA outcomes are revised should opportunities for voluntary enhancements be identified and progressed as these should significantly impact upon the natural capital outcomes.

Based on the risks and opportunities set out Table 7‑1, the following recommendations for the proposed scheme design are made:

Compensatory woodland planting and enhancement measures are considered in a strategic manner to realise multiple benefits. These could include optimisation for air pollutant removal, carbon reduction, soil erosion protection and implementation as part of a NBS to address downstream flood risk. Additionally, the impact on local landscape character should be carefully considered.
The removal of woodland habitats as part of the proposed scheme, particularly on valley slopes, should be carefully considered in terms of the potential impact on flood risk and soil stability. Further investigation should be considered.
There are opportunities to support pollinators through proposed scheme planting. Pollinator surveys could help to evidence and optimise the potential benefits.
Provisioning of access to cuttings which result in the creation of new geological features, a possibility identified for the proposed scheme, could generate significant education benefit and enhance the already important geological heritage of the Dunkeld and Little Glen Shee area.
Supporting local volunteering initiatives such as environmental groups which carry out ecological surveys and tree-planting could deliver benefits to the community whilst promoting Positive Effects for Biodiversity in alignment with the NPF4 requirement.
The recreation benefits are highly important in the overall NPV for natural capital associated with the proposed scheme. These benefits rely on the following assumptions: that the new path proposed connecting Ring Wood to the Dalpowie plantation links with accessible, existing paths through Dalpowie which eventually connect to the Murthly River Path; and that the enhancements to the River Braan OAA/Inver area create a new circular route and significantly improve the accessibility of Path 35 for more WCH. Designs should ensure that these assumptions are realised to truly benefit local recreation.

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