Greybeard33
Established Member
See https://cdn.networkrail.co.uk/wp-co...odate-forecast-growth-on-the-CLC-corridor.pdf. "How to accommodate forecast growth on the Cheshire Lines Committee (CLC) corridor? Railway investment choices". (The CLC line links Manchester and Liverpool via Warrington Central.)
AFAIK this Network Rail report has not been discussed on the forum before, although it is dated October 2019. It presents the results of in-house NR capacity and BCR modelling, but also refers (approvingly) to an AECOM report on the line that was commissioned by Merseytravel, Warrington Borough Council and TfGM (I do not think the AECOM report is in the public domain).
The capacity modelling in the report covers the portion of the line between Edge Hill East Junction and Trafford Park West Junction; it does not address capacity issues in the Castlefield corridor or the Lime Street approaches, which are the subject of separate NR studies. The main issues identified are peak overcrowding on the eastern part of the line, between Warrington and Manchester; and poor service reliability. The crowding already exceeds DfT standards and is forecast to get progressively worse unless something is done.
The report evaluates a range of infrastructure and rolling stock interventions, focussing on combinations of platform lengthening and SDO to enable 6-car trains to be used, plus shorter block sections and a new turnback at Warrington Central to enable 4tph between Warrington and Manchester. However, the Value for Money category is assessed as no better than Medium, because the benefits of the investment would be concentrated mainly in the high peak hours. Electrification is not mentioned.
An alternative proposal, lifted from the AECOM report, is to split the stoppers into separate but overlapping west and east services, Lime Street to Birchwood and Warrington West to Oxford Road. This would require a crossover, loop and turnback at Warrington West, and a crossover at Birchwood. The two semi-fasts would be retained as through services, but reliability would improve because they would be less tightly constrained between the stoppers. Higher performance rolling stock would be introduced to improve journey times. AECOM assessed the BCR of this package as better than 2.0, but using more optimistic assumptions than NR. Nevertheless, the NR report recommends that this proposal should be taken forward for more detailed analysis.
For the longer term, the report recommends feasibility studies of a Merseyrail extension to Warrington and Metrolink-style services at the eastern end of the line, to further improve frequency and capacity, while NPR would potentially abstract the Manchester - Warrington - Liverpool passengers.
The Executive Summary concludes:
In my opinion, the NR study may have underestimated the benefits of releasing repressed demand, through the provision of higher capacity, more reliable services. Particularly if frequency is improved at the smaller stations in GM, which currently have only 1tph or 1tp2h.
Note: this Infrastructure thread is intended only for discussion of the proposals in the linked NR report. If you wish to put forward your personal ideas for changes to the CLC line infrastructure and/or services, please start a new thread in the Speculative Ideas section of the forum.
AFAIK this Network Rail report has not been discussed on the forum before, although it is dated October 2019. It presents the results of in-house NR capacity and BCR modelling, but also refers (approvingly) to an AECOM report on the line that was commissioned by Merseytravel, Warrington Borough Council and TfGM (I do not think the AECOM report is in the public domain).
The capacity modelling in the report covers the portion of the line between Edge Hill East Junction and Trafford Park West Junction; it does not address capacity issues in the Castlefield corridor or the Lime Street approaches, which are the subject of separate NR studies. The main issues identified are peak overcrowding on the eastern part of the line, between Warrington and Manchester; and poor service reliability. The crowding already exceeds DfT standards and is forecast to get progressively worse unless something is done.
The report evaluates a range of infrastructure and rolling stock interventions, focussing on combinations of platform lengthening and SDO to enable 6-car trains to be used, plus shorter block sections and a new turnback at Warrington Central to enable 4tph between Warrington and Manchester. However, the Value for Money category is assessed as no better than Medium, because the benefits of the investment would be concentrated mainly in the high peak hours. Electrification is not mentioned.
An alternative proposal, lifted from the AECOM report, is to split the stoppers into separate but overlapping west and east services, Lime Street to Birchwood and Warrington West to Oxford Road. This would require a crossover, loop and turnback at Warrington West, and a crossover at Birchwood. The two semi-fasts would be retained as through services, but reliability would improve because they would be less tightly constrained between the stoppers. Higher performance rolling stock would be introduced to improve journey times. AECOM assessed the BCR of this package as better than 2.0, but using more optimistic assumptions than NR. Nevertheless, the NR report recommends that this proposal should be taken forward for more detailed analysis.
For the longer term, the report recommends feasibility studies of a Merseyrail extension to Warrington and Metrolink-style services at the eastern end of the line, to further improve frequency and capacity, while NPR would potentially abstract the Manchester - Warrington - Liverpool passengers.
The Executive Summary concludes:
This study recommends therefore the progression of the report prepared by AECOM, and the pursuit of their recommended interventions required to drive connectivity along the CLC Corridor. A Strategic Outline Business Case (SOBC) should be developed. It is also recommended that further investigation into potential interventions that seek to address future capacity issues along the rail corridor takes place.
In my opinion, the NR study may have underestimated the benefits of releasing repressed demand, through the provision of higher capacity, more reliable services. Particularly if frequency is improved at the smaller stations in GM, which currently have only 1tph or 1tp2h.
Note: this Infrastructure thread is intended only for discussion of the proposals in the linked NR report. If you wish to put forward your personal ideas for changes to the CLC line infrastructure and/or services, please start a new thread in the Speculative Ideas section of the forum.