A30 between Temple & High duelling
Case reference EIR2026/00043
Received 12 January 2026
Published 4 March 2026
Request
Strand One Request (Sub-paragraph (a) of my EIR request dated 8 December 2025)
The ‘Monitoring Reports’ of the effects of the Duelling of the A30 Highway from Temple to Higher Carblake that the Highways Agency were required to make over four years from October 2019; these ‘Monitoring Reports’ are required to be made by paragraph 1.1.4 of the Post Construction Monitoring Plan required by, and then approved in accordance with, Statutory Instrument 2015-147; there is a statutory requirement to complete these monitoring reports covering the four years from October 2019 by October 2023.
This includes the monitoring reports required to be produced over the five-year post-construction monitoring period, namely:
• Year 1 monitoring undertaken by Cornwall Council; and
• Years 2–5 monitoring undertaken by the Highways Agency / National Highways.
Amplification – Strand One
Paragraph 17 of Schedule 2 of Statutory Instrument 2015-147 imposes a clear and unequivocal statutory obligation that post-construction monitoring must be carried out in accordance with an approved Post Construction Monitoring Plan. That obligation covers a five year monitoring period following completion of the construction authorised by SI2015-147. You can conveniently access SI 2015-147 by following this link:
https://www.legislation.gov.uk/uksi/2015/147/contents
I attach a copy of the Statutorily Approved Post Construction Monitoring Plan that was required by Section 17 of SI2015-147; you will see that Section 1.1.4 of this placed a statutory requirement on Cornwall Council to produce a One Year Review of the efficacy of the Duelled A30 and that National Highways were responsible for the review of the next four Years.
You have kindly drawn my attention to the One Year Post Opening Project Evaluation Report produced by National Highways and published in January 2023. I therefore request:
• Copies of any further annual monitoring reports produced for Years 2–5 of the monitoring period; or
If no such reports were produced, a clear statement confirming that no further monitoring reports exist or are held by National Highways.
Strand Two Request (Sub-paragraph (b) of my EIR request dated 8 December 2025)
The authority by which National Highways constructed and compiled the ‘One Year Review’ required by paragraph 1.1.4 of the Post Construction Monitoring Plan (PCMP) when it was statutorily required that this Review was to be conducted by Cornwall Council.
Amplification – Strand Two
The PCMP approved pursuant to SI 2015-147 clearly allocates responsibility for Year 1 post construction monitoring to Cornwall Council. However, the One-Year Post-Opening Project Evaluation Report was undertaken and published by National Highways.
I therefore request disclosure of the formal authority (whether by delegation, agreement, or amendment to the PCMP) that permitted National Highways to discharge Cornwall Council’s statutory Year 1 monitoring obligation. If no such written authority is held, I should be grateful for a statement confirming that no such authority exists or is in your possession.
Strand Three Request (Sub-paragraph (c) of my EIR request dated 8 December 2025) The authority for the delay in completion of the Year 1 post-construction monitoring report from its statutory due date, October 2019, to its eventual publication in January 2023
Amplification – Strand Three Section 1.1.4 of the approved PCMP, attached, requires monitoring at the one year post opening stage. The One Year Post Opening Project Evaluation Report was not completed until January 2023, approximately four years and three months after completion of the authorised development.
I therefore request disclosure of the authority or decision that permitted this delay. If no such authority exists or is held, I should be grateful for a statement confirming this.
Strand Four Request (Sub-paragraph (d) of my EIR request dated 8 December 2025) The ‘Five Year Report’ into the ‘Water Environment’ articulated on page 62 of the National Highways A30 Temple to Higher Carblake Dualling One Year Post-Opening Project Evaluation Report dated January 2023; this Five Year Report is required by paragraph 1.1.4 of the Post Construction Monitoring Plan.
Amplification – Strand Four I regret that I cited an incorrect page number in my FOI EIR request of the 8th of December 2025. The correct references are pages 34–35 of the One Year Post Opening Project Evaluation Report published by National Highways in January 2023.
Those pages state that:
• Information relating to drainage performance and water quality monitoring was unavailable at the one year stage; and
• The impacts on the water environment “should be reconsidered at five-years after.”
I therefore request a copy of the five-year post-construction monitoring report for the water environment that was statutorily required to be produced in compliance with the approved PCMP and Schedule 2 of SI 2015-147. If no such report has been produced, I request that this be explicitly confirmed within the basis for non disclosure under the Environmental Information Regulations.
I trust that the clarification above assists in identifying the precise environmental information requested. I look forward to your response within the statutory timescale.
Response
I can confirm that we hold some of the information you have requested.
Information provided
Strand One
Sub-paragraph (a) of my EIR request dated 8 December 2025)
The ‘Monitoring Reports’ of the effects of the Duelling of the A30 Highway from Temple to Higher Carblake that the Highways Agency were required to make over four years from October 2019; these ‘Monitoring Reports’ are required to be made by paragraph 1.1.4 of the Post Construction Monitoring Plan required by, and then approved in accordance with, Statutory Instrument 2015-147; there is a statutory requirement to complete these monitoring reports covering the four years from October 2019 by October 2023. This includes the monitoring reports required to be produced over the five-year post-construction monitoring period, namely:
• Year 1 monitoring undertaken by Cornwall Council; and
• Years 2–5 monitoring undertaken by the Highways Agency / National Highways.
Amplification – Strand One
Paragraph 17 of Schedule 2 of Statutory Instrument 2015-147 imposes a clear and unequivocal statutory obligation that post-construction monitoring must be carried out in accordance with an approved Post Construction Monitoring Plan. That obligation covers a five year monitoring period following completion of the construction authorised by SI2015-147. You can conveniently access SI 2015-147 by following this link: https://www.legislation.gov.uk/uksi/2015/147/contents. I attach a copy of the Statutorily Approved Post Construction Monitoring Plan that was required by Section 17 of SI2015-147; you will see that Section 1.1.4 of this placed a statutory requirement on Cornwall Council to produce a One Year Review of the efficacy of the Duelled A30 and that National Highways were responsible for the review of the next four Years. You have kindly drawn my attention to the One Year Post Opening Project Evaluation Report produced by National Highways and published in January 2023.
I therefore request copies of any further annual monitoring reports produced for Years 2–5 of the monitoring period; or If no such reports were produced, a clear statement confirming that no further monitoring reports exist or are held by National Highways.
We hold one report – ‘CEC2541d dormouse license monitoring 2017- 2021_Redacted’, attached.
Personal information has been withheld under Regulation 13 of the Environmental Information Regulations 2004.
Information not held
Strand Two Request
Sub-paragraph (b) of my EIR request dated 8 December 2025)
The authority by which National Highways constructed and compiled the ‘One Year Review’ required by paragraph 1.1.4 of the Post Construction Monitoring Plan (PCMP) when it was statutorily required that this Review was to be conducted by Cornwall Council.
Amplification – Strand Two
The PCMP approved pursuant to SI 2015-147 clearly allocates responsibility for Year 1 post construction monitoring to Cornwall Council. However, the One-Year Post-Opening Project Evaluation Report was undertaken and published by National Highways.
I therefore request disclosure of the formal authority (whether by delegation, agreement, or amendment to the PCMP) that permitted National Highways to discharge Cornwall Council’s statutory Year 1 monitoring obligation. If no such written authority is held, I should be grateful for a statement confirming that no such authority exists or is in your possession.
Strand Three Request
(Sub-paragraph (c) of my EIR request dated 8 December 2025) The authority for the delay in completion of the Year 1 post-construction monitoring report from its statutory due date, October 2019, to its eventual publication in January 2023.
Amplification – Strand Three Section 1.1.4 of the approved PCMP, attached, requires monitoring at the one year post opening stage. The One Year Post Opening Project Evaluation Report was not completed until January 2023, approximately four years and three months after completion of the authorised development.
I therefore request disclosure of the authority or decision that permitted this delay. If no such authority exists or is held, I should be grateful for a statement confirming this.
I can confirm that National Highways does not hold this information, and as such this part of your request has been refused under Regulation 12(4)(a) of the Environmental Information Regulations 2004 as information not held.
Advice and Assistance
Strand 2 – We believe this information may be held by Cornwall Council and if you have not done so already you may wish to contact them.
Strand 3 - Our understanding is that the works on A30 mainline were completed in 2017 but that associated environmental works continued on until October 2018. Our one year after post opening project evaluation (POPE) was published in Jan 2023 but the analysis was undertaken using data for 2019 and 2020.
The Covid pandemic impacted the timing and delivery of much of our analysis during 2020. Lockdowns and travel restrictions also affected the timing of our environmental evaluation site visits. Typically, we undertake these visits during the summer to ensure we can observe the effect of mitigation planting but in the case of the A30 the visit was delayed until the September.
Our POPEs are a standard process which we undertake on all major projects on our network. They are, in part, done to support our Licence issued under the Infrastructure Act 2015. Our 5 year after POPE should be published later this year.
Documents
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