Safety issues when trams run over temporary track during say utility relocation / diversions

From David Walmsley:
I am not at all certain that running trams over excavations would be acceptable in the UK. It goes against the NRSWA safety code.  (NRSWA = New Roads and Street Works Act 1991)
Utilities and transport companies both tend to be municipally owned on the continent. So decisions on repairs or replacement can be made in their common interest.  In the UK,  utilities are privatised, and they are powerful and see tramways as intruders.

From Alan Wilkins:

I believe David Holt is right to question David Walmsley’s statement that the NRSWA safety code prohibits work over excavations.  Surely the NRSWA governs the long term relationship between utilities, trams, and works in streets in general, including the all important matter of who pays for what.
I believe that the actual carrying out of work in streets, for whatever reason, comes under the auspices of the Health and Safety at Work Act (HASAWA) and its associated statutory instruments issued under its cover.  The general HASAWA principle is the elimination, or if that is not possible, the reduction of risk to all parties involved to ‘as low as reasonably practicable’ (ALARP.)  So, if you wish to construct a new, enhance, renew, or maintain an existing tramway you must do the necessary risk assessments, and then put in place the requisite precautions and mitigations.
In the UK, HASAWA etc is often seen as a prohibition of what some perceive as normal practice in Europe.  That broad brush ignores the very substantial differences in practice within Europe which pertain for numerous localised reasons.  Trams are sometimes permitted to pass through repair and renewals sites, at suitably reduced speed, and with other safety features, such as barriers and gates, in place.  Not all European renewals etc. can be so performed, and total closure of the relevant part of the tramway is sometimes necessary.  In some cities trams can be diverted to alternative routes where they exist, or, as in the UK, substitute buses are provided.  Has anyone any personal experience of performing a risk assessment for the use of Kleterwich (my spelling is probably incorrect) switches for single line operation around maintenance work in the UK? – I do not have such experience.
I hope this provides some clarity regarding the safety of tramway works in streets.  I would be pleased to read other correspondents views and insights.
Alan Wilkins
From David Rumney

David W is quite right, but it doesn’t stop there. The relevant section of the code, issued under s.65 of NRSWA, is contained in pages 74 to 77 of the October 2013 revision of the Safety at Street Works and Road Works Code of Practice. The section starts off with the following:

“Warning: Before carrying out works in a street with a tramway, the tramway operator and highway authority must be consulted. The tramway operator will set out safety requirements to ensure safe working and to minimise the impact of works on operation of the tramway. These requirements must be followed.”

This goes along with s.93 of NRSWA on which this part of the Code is based. Subsection 93(3) says:

“An undertaker executing works to which this section applies shall comply with any reasonable requirements made by the relevant transport authority—

(a) for securing the safety of persons employed in connection with the works, or

(b) for securing that interference with traffic on the railway or tramway caused by the execution of the works is reduced so far as is practicable;

and, except where submission of a plan and section is required, he shall defer beginning the works for such further period as the relevant transport authority may reasonably request as needed for formulating their requirements under this subsection or making their traffic arrangements.”

A tramway operator needs to have its own code of practice relating to work near to the tramway so that it can readily provide the requirements for safe working close to the tramway. The first of these was developed for Manchester Metrolink in conjunction with Kit Holden and Steven Firth. This was also used as the basis for the Midland Metro and Sheffield tramways, and I imagine will also have been used with whatever modifications were necessary by all the other tramway operators.

A further consideration is s.82 of NRSWA. This says that a utility will have to compensate a relevant authority for any damage or loss resulting from work carried out by the utility. This applies regardless of whether the damage results from work carried out due to a failure of the apparatus or is straightforward repair work. Consequently the utility would be naïve to agree to leave apparatus in close proximity to a tramway unless it receives a waiver from this section (as was done in Birmingham for Severn Trent Water). Similarly the tramway operator would not sensibly agree to work being carried out in such a way as to mean that he was unable to recover costs and loss of profit if appropriate.

In my 30 years of involvement with tramway works I have frequently been embarrassed by peoples’ ideas about utility apparatus and how simply it can be dealt with by doing nothing. I’m sure that it will transpire that this was the approach adopted by TIE in Edinburgh. Please don’t get sucked into the same illusion: apparatus comes in many shapes and sizes, and lies at many depths below the road. It is vital that you know what is there long before work starts on building the tramway to understand just what will be required and when diversion work will need to be carried out. As David W has pointed out elsewhere, the utilities are extremely powerful, for good reason – they are what allow us to live in houses rather than caves –  and if you mess with them they will roll you into the ground.

David Rumney



From: David Holt

I wonder in what particular respect(s) it goes against the NRSWA safety code.  There are two obvious possibilities – the risks to Utilities workers from trams running above them while they work or obtain access/egress, or the risks of trams falling off temporarily-supported track, or an obvious combination of both, or the risks of the temporary supports collapsing, or of gas being ignited by tram sparking, or of some sort of clash between the two activities, or whatever else could be imagined.  Mitigations might be possible – such as doing the under-track work only when the trams aren’t running, at night for example.