Cambridge Light Rail would be a significant investment. However, built over ten years in two main phases, the overall investment of £1.4 bn is realistically feasible. Phase One of the Isaac Newton Line, which includes 19 km of overground line including 2.6 km of tunnel and two underground stations could be delivered for less than £1 bn. This compares to an initial investment of £800 M in Nottingham NET light rail, so this level of investment is realistic and affordable, especially in Cambridge. As another comparison, Manchester Metrolink invested £1.7 bn just in extensions over ten years. The combined resources of Cambridge stakeholders could be leveraged with the Greater Cambridge City Deal and Central Government support. With a strong business model, there are investors that would be willing to commit resources to Cambridge infrastructure as a long-term investment.
The costs of Light Rail and rapid transit varies vary widely according to local conditions and constraints, and it is impossible to provide an accurate costing of the Cambridge Light Rail system at this juncture. This said, comparisons against other examples give some appreciation of the order of investment required. These costs are indicative, although are anticipated to be broadly in range. Some costs may be significantly less: for example, a cut and cover underground station at Parkside may be possible, and if so then the cost could be substantially less than the £100 M allocated at this stage.
Cambridge Light Rail cost estimate summary1
| U-ground (km) | O-ground (km) | Total (km) | Stops2 | U-ground £M3 |
O-ground £M |
Total £M | |
| Isaac Newton Line Phase One |
2.6 | 17 | 19.7 | 15 | 392 | 529 | 921 |
| Darwin Line Phase One |
0 | 2.2 | 2.2 | 3 | 0 | 57 | 57 |
| Isaac Newton Line Phase Two | 0 | 11.7 | 11.7 | 4 | 0 | 295 | 295 |
| Darwin Line Phase Two | 0 | 6.5 | 6.5 | 5 | 0 | 165 | 165 |
| TOTAL |
2.6 | 37.4 | 40.1 | 27 | 392 | 1046 | 1438 |
| Comparison | |||||||
| Métropole Nice Côte D’Azur 4 |
3.2 | 11.3 | 14.5 | 24 | 205 | 586 | 791 |
1. Estimate: detailed cost appraisal not yet undertaken. Includes lines, tunnel, 2 u-ground stations, surface stations, rolling stock, depot.
2. Existing Cambridge Central Rail Station and proposed new Cambridge South Rail Station are counted as Cambridge Light Rail stops.
3. Underground costs based on £73.5 M/km and INCLUDES two underground stations @ £100 M each. Published cost of underground Métropole Nice Côte D’Azur Line 2, Railway Gazette (Oct 2015) and estimated cost of 4.25 m diameter tunnel in Cambridge geology of £73.5 M/km for bi-directional tunnel.
4. Overground Light Rail cost of £20-30M /km B. Menzies (2015) quoted Cambridge News 03 Feb 2015. £25M /km used above.
The Métropole Nice Côte D’Azur Line 2 was selected for comparative purposes mainly because the length and number of stops were similar to those proposed in the Cambridge Light Rail model, and because it is a recent scheme undertaken in a modern European economy with some degree of similarity to the UK. The line is now operational.
Underground costs were considered separately from overground because of their expense. Rough overground costs for Light Rail were estimated at £25M per km of track, the mid-point of a rough estimate by Bob Menzies (former Director of Strategy & Development in Economy, Transport and Environment Services, Cambridgeshire County Council), which seems realistic given a recent professional costing of around £31M per km of track for a bi-directional heavy rail line in the local region (WSP Parsons Brinkerhoff 2015. Cambridge-Haverhill Corridor study. Draft rail viability technical note. Report for the Cambridgeshire County Council Nov 2015). Light Rail is generally considered less expensive to install than heavy rail, and new technologies are pressing costs downward.
Some comparisons…
Let’s put these numbers into some perspective…
| Project | Total £M | Source |
| Greater Cambridge City Deal (67 M /y over 15 y) | 1000 | GC City Deal |
| NW Cambridge development (3000 new homes, schools, shops etc) | 1000 | University of Cambridge |
| A14 improvements Cambridge – Huntingdon | 1500 | Highways Agency 2016 |
| 25 km of UK motorway (2011) | 480 | Avg – BBC News |
| 21 km Cambridge – Haverhill double-track heavy rail line – costing appraisal | 652 | WSP Parsons Brinkerhoff 2015 |
Meeting the costs of a Cambridge Light Rail network clearly represents a challenge. However, when considered against other large-scale infrastructure investments in recent years, the overall cost is within reasonable bounds, and the value added will be high.
The investment needs to be considered in the perspective of the overall benefits that would result. Cambridge Connect believes that the Cost / Benefit ratio could prove worthwhile when all of the benefits to the economy, residents, visitors, University, business, environment, heritage and for sustainability are taken into account. This is a major investment, with major potential benefits. We believe it is realistically achievable when progressed in manageable stages.
