Each clock shows the confirmed active cost overrun for that jurisdiction, compounding in real-time at the blended BCIS construction inflation rate for that portfolio. Clock base excludes completed and cancelled schemes. ROI denominated in €; all others in £.
| Rank | Jurisdiction | CPD-C (Cost) | Cost Overrun | CPD-D (Delivery) | Avg Delay | Max Delay | Combined | Score Bar | Dashboard |
|---|
CPD Combined = weighted score: 60% CPD-D (Delivery) + 40% CPD-C (Cost). Delivery is weighted higher to reflect that delay is the primary accountability failure in public infrastructure. Higher score = better performance. Ranked worst to best by Combined score.
CPD Combined Index — All Jurisdictions
CPD-C vs CPD-D — Cost vs Delivery Split
Average Delay by Jurisdiction (weeks)
Portfolio Status Breakdown — Schemes by Status
Cost Overrun % — Announced vs Current by Jurisdiction
England: highest score, worst absolute overrun
A Combined CPD score of 84 — CPD-C 88, CPD-D 82 — is the second-highest in the tracker, but the absolute overrun value dwarfs all others across HS2, Hinkley Point C, smart motorway cancellations, and West Midlands Metro. Eight schemes cancelled outright; 16 in significant delay. The 40-scheme portfolio has grown from £28bn announced to £67bn current estimate (+138%). Average delay across the English portfolio: 289 weeks — over five and a half years per scheme. HS2 Phase 1 alone has slipped by over a decade from its original opening.
ROI has the worst cost record in the islands
The Republic of Ireland's Combined score of 85 — CPD-C 86, CPD-D 85 — is the best-performing jurisdiction in the tracker across 40 schemes, but hides the worst cost overrun record: the 40-scheme portfolio has grown from €20bn announced to €46bn current (+124%). The National Children's Hospital has missed 18 confirmed deadlines and remains unfinished after 12 years. MetroLink, National Maternity Hospital, and BusConnects Dublin (€1bn → €3bn) all show systemic cost underestimation.
Northern Ireland announces but doesn't build
NI's 40-scheme Combined score of 70 — CPD-C 63, CPD-D 75 — reflects a pattern of schemes paused for years before a brick is laid. A5 (2007 announcement, no metre built — 885 weeks and counting), Casement Park, the North–South Interconnector (2006→2031), and Strule Campus (2020→2028) together represent decades of inertia. Average delay across the NI portfolio: 312 weeks — six years per scheme. 7 schemes currently paused.
London: world-class projects, world-class delays
A Combined score of 71 — CPD-C 69, CPD-D 72. Crossrail arrived 4 years late and £4.1bn over. The Piccadilly Line upgrade is a year behind before it opens. Hammersmith Bridge has been closed to traffic since 2019 with costs rising 525%. Four Lines Modernisation is 7 years overdue. Average delay across the London portfolio: 261 weeks — five years per scheme. A CPD-C of 69 reflects persistent cost overruns — though better than the national average, the scale of individual failures like Crossrail and HS2 Euston distorts the picture considerably.
Wales: best delivery record in GB/NI
Wales' Combined score of 65 — CPD-C 45, CPD-D 78. Wales holds the best delivery score (CPD-D 78) of all five GB/NI jurisdictions — the strongest record for actually progressing schemes. Average delay across the Welsh portfolio: 233 weeks — under four and a half years, the shortest average delay of any GB/NI jurisdiction. Three cancellations (M4 Relief Road, Swansea Tidal Lagoon, Circuit of Wales) weigh heavily on the cost score, but where schemes proceed, Wales delivers more reliably than its peers.
Scotland: weakest delivery score, and costly too
Scotland's Combined score of 63 — CPD-C 56, CPD-D 68. CPD-D 68 is the weakest delivery score of all British Isles jurisdictions. Average delay across the Scottish portfolio: 390 weeks — seven and a half years per scheme, the longest average delay of any jurisdiction in the tracker. The A9 Dualling has slipped a full decade (2025→2035). Ferguson Marine (374% overrun), NHS Grampian (227%), HMP Glasgow (150%) compound the delivery failure with severe cost overruns.
Methodology
CPD Index: The CPD (Continued Prolonged Delays) Index is a composite accountability score on a 0–100 scale, where 100 indicates perfect delivery and 0 indicates total failure. It is split into two sub-indices: CPD-C (Cost Performance) — the proportion of schemes delivered at or near announced cost, with a severity penalty for overruns above 25%; and CPD-D (Delivery Performance) — the proportion of schemes free from significant delay, with a minor penalty for smaller slippages. The Combined CPD score applies a 60/40 weighting — 60% CPD-D (Delivery) and 40% CPD-C (Cost) — reflecting the judgement that delivery failure is the primary accountability issue in public infrastructure. A scheme that costs more than announced but is eventually built is a lesser failure than one that has not been built at all. Cancelled and completed schemes are included in the scoring.
Live clocks: Each jurisdiction clock shows the confirmed active cost overrun (excluding completed and cancelled schemes) compounding in real-time at the blended BCIS construction inflation rate for that portfolio type. The rate represents the additional cost of delay rather than new construction expenditure.
Sources: Audit Wales · Audit Scotland · NI Audit Office (NIAO) · Comptroller & Auditor General (C&AG, ROI) · National Audit Office (NAO, UK) · Infrastructure & Projects Authority (IPA) · Transport Infrastructure Ireland (TII) · Transport Scotland · Transport for Wales · HS2 Ltd Parliamentary Reports · TfL Annual Reports · GLA Budget Papers · BBC News · Irish Times · The Guardian · Financial Times · Institute for Government
Disclaimer: This tracker is an independent professional assessment prepared by QuintinQS. It is not affiliated with any government body. All figures are drawn from publicly available sources. Cost projections are illustrative only, based on BCIS inflation assumptions.