Metroisation Corridor Plan

1) Partnership and scope 

Establish a delivery partnership spanning GBR/Network Rail, local and combined authorities, Homes England, operators and community partners. Confirm the corridor extent (30–80 km) and identify any ConnectedCities within it. 

2) Use the Better Value Rail (BVR) Toolkit from the outset 

Apply BVR’s sequence—Strategy → Explore → Examine → Culture & Capability—to frame the transport problem, compare mode/operating options, set early specifications and surface risks and evidence before formal business‑case stages. 

3) Gear‑based delivery with timetable‑first in Gear 1 

Gear 1 (today): timetable‑first recast before infrastructure. Re‑plan the timetable to even out headways, simplify stopping patterns and minimise conflicts, with robust turnback margins and platforming consistent with Train Planning Rules. Implement local shuttle overlays where feasible to isolate perturbations and improve right‑time performance. Only then consider minimal capital interventions (e.g., minor signalling changes or platform reinstatement) if the recast cannot achieve the required performance. 

Gear 2 (metro‑level): commit the integrated corridor package. Move to the agreed metro pattern once triggers are met (for example: pooled value‑capture mechanism in place; station access schemes funded; a defined share of station‑area homes consented) so frequency uplift and growth advance together. 

4) Diagnose and treat pinch points 

Run capacity and timetable analysis to expose junction conflicts, single‑track constraints, platform occupation clashes and TSR‑sensitive sections. Build a targeted works list with costs, benefits and delivery windows (e.g., Westbury Platform 0, Melksham passing loop, Thingley Junction improvements) to unlock tph step‑ups and improve performance resilience. 

5) Engineer the service concept for robustness 

Use local shuttles to separate stopping patterns from intercity and freight, improving punctuality and recovery. Apply clock‑face patterns across the entire corridor and coordinate with feeder bus timings and active‑travel access plans. 

6) Scope stations, access and place‑making together 

Specify step‑free access, safe walking and cycling routes and bus interchange. Define Town Growth Zones and New Green Towns with station‑area frameworks to deliver gentle‑density housing within ~1 km and lock in rail‑first trip patterns. 

7) Build the funding and delivery model 

Adopt a corridor‑wide plan that pools land‑value uplift, developer contributions and business‑rates retention (e.g., via Station Iinvestment Zones), alongside farebox growth and public co‑investment; align with Homes England and, where relevant, Mayoral Development Corporations. 

8) Metrics and accountability 

Report corridor‑level outcomes annually: frequency and reliability, mode share for trips under 10 km, emissions per passenger‑kilometre, step‑free coverage, and delivery of station‑area homes and jobs. 

9) Pilot, prove and scale 

Phase early timetable improvements and low‑cost fixes at pinch points; introduce shuttle‑based patterns where they add resilience; then scale to the full metro headway as Gear‑2 triggers are satisfied (for example: Platform 0 at Westbury, Melksham loop, Chippenham and Frome platform works, and a Thingley improvement).