Crescent Road Level Crossing Renewal Merseyrail SSI Assessment Southport [03] Interlocking

Crescent Road Level Crossing is an AHBC located on the Up and Down Southport lines; ELR HXS3, at 16 miles and 76 chains between Birkdale and Hillside stations. The crossing has its control circuitry located in an REB at the crossing and is within the Merseyrail STHPORT(03) SSI area supervised from the Northern Lines Workstation located in Sandhills IECC. STHPORT(03) has 2 fringes; BOOTLE(02) SSI (also controlled from the Northern Lines Workstation at Sandhills IECC) and Burscough RRI located at Burscough Bridge Junction SB. 

The signalling within this area is a mixture of 2 and 3 aspect before raising back to 3-aspect once trains have passed the crossing on either side. This is being altered to 3-aspect through Crescent Road Level Crossing on the Down Southport line as part of this project.

The existing Level Crossing is within the STHPORT(03) SSI area. Its control and indication functions are managed by the SSI through TFM outputs and inputs.

The Level Crossing is to be renewed as a 4 barrier MCB-OD, noting the OD system to be utilised is the product approved Mark 1.

The aspiration of the project is that all required level crossing controls, indications, and strike-ins will be managed in STHPORT(03) SSI data.

Our Role

As SSI is already becoming an ageing technology on the UK rail network, before making alterations to an existing installation, its imperative to carry out an assessment on that SSI interlocking to ensure that it is fit for alteration.

On the Crescent Road Level Crossing Renewal project DigiSig Rail were approached by Mosaic Rail to undertake this assessment, to offer our expertise on SSI interlockings and produce a report containing our findings of the state of the existing STHPORT(03) installation and advise the project on whether we deemed it fit for alteration. Details of the assessment are as below.

This assessment has been carried out against Network Rail Standards (Issue 119) that were current in March 2021 (to which scheme sketch version 0.3 was produced) and all Reference Documents information as detailed above.

Also, a site visit to Sandhills IECC was made on 09/05/2022 to gather information as to the current condition and performance of STHPORT(03) SSI.

The assessment is of ‘STHPORT(03)’ and is made against the following criteria to determine the suitability for the alterations required by the project scope:

    • Interlocking Capacity
    • TFM Capacity
    • EPROM Capacity
    • Identity Capacity
    • Interlocking Condition
    • Data Complexity & Volume
    • Data/Compiler/Program Compatibility
    • Data/Program Condition
    • Standards and Retrospective Amendments
    • Timing Assessments
    • Assessment of Proposed Changes

You can download the latest case study by clicking here

Project Information

  • Project Title: Crescent Road Level Crossing Renewal
  • Client: Mosaic Rail
  • Date: May 2022
  • Category: Signalling Specification
  • Status : Completed