Statutory Utilities Examples

This case study details some real-world examples that the Thameslink Programme team came across while dealing with statutory utilities at London Bridge station and the surrounding area.

Statutory Utilities

What do we mean by statutory utilities?

A statutory utility is a supplier of electricity, water, gas or telecoms licensed by the government. This license grants them statutory powers, among which is the right to locate their services in the public highway. These rights can have a powerful influence over the way we deliver our projects.

What are the two groups of statutory utilities?

Firstly there were those utilities that the Thameslink Programme required itself, e.g. the water, gas, telecoms and electricity supplies that would be used by the stations and properties.

Secondly, there were the existing utilities, usually in the public highway and a great many of them in the way of what we were trying to build. Under the New Roads and Street Works Act, any utility diversions on the public highway must be carried out by following the process laid out in the Diversionary Works Code of Practice.

The statutory utilities are protected by legislation which means careful negotiation is required in order to find the best solutions for the programme. One point worth noting is that even when we pay for a diversion Statutory Utilities are not under contract to us in the normal sense of the word.

Where a project needs to divert unforeseen pipes and cables, it can create an unexpected burden for a project. This usually manifests itself in delays and increased costs. Poor management of statutory utility work will import similar risks.

Case study examples

This case study looks at a few real-world examples that the Thameslink Programme team came across during the enabling works and the main redevelopment of London Bridge station. Without early identification, careful planning and subsequent review after the works, each of them could have resulted in huge unexpected costs and delays to the project.

The first few steps in each of these examples were to:

  • Establish what was in the ground.
  • Decide if the existing utilities were covered by powers relating to statutory utilities.
  • Decide if ‘wayleaves’ would be required for utilities beneath Network Rail property. If they are, the process needs to be started as soon as possible due to the timescales required.
  • Establish who would be expected to pay the costs to divert or relocate any services.
  • Decide if this work qualifies for the ‘Sharing of Costs’ scheme.

 

Example 1 – Fibre optic cable disruption beneath Stainer Street (Public highway access through Network Rail property)

An underground duct carrying fibre optic telecoms cables was identified beneath the pedestrian walkway and concourse in Stainer Street within the London Bridge station boundary.

Each buried duct carried three or four fibre-optic cables belonging to multiple telecoms utility companies. These would have to be disturbed, replaced and re-buried during construction and so contact was made with the various supply companies. The project team offered to replace the entire length of the ducts during the work allowing the various companies to re-lay their cables with only very minor disruption to services.

However, one of the telecoms providers insisted that they needed to be able to access and maintain their cables in the public highway at all times. They proposed a design where the cables would be re-laid right around the perimeter of the station, outside the station boundary.

However, the time, cost and the logistics for the project to do this were going to be excessive. Through lengthy negotiations, the station team were able to show that the Stainer Street route through the station was in fact better in many ways. For example, it was unlikely to ever be disturbed by excavation, meaning no third-party damage and consequently no outages, unlike on the public highway. The distance between access points to the cables would be no more than normal and access would be from the public highway at either end of the street, meaning 24/7 access should they need it. There would also be a lot less cable length required meaning less fault liability and less future maintenance work.

 

Example 2 – Gas diversion from Weston Street around London Bridge station to St Thomas Street (Public highway)

During the station redevelopment, the large gas main that passed along Weston Street would need to be diverted around the outside of the station and back along St Thomas Street. The new station’s predicted gas demand was expected to increase significantly as they would be using a combined

heat and power system plus there would be many more retail and restaurant units. For this reason, it was important to estimate the demand and specify a larger

capacity main for the diversion. This would require an uplift to the project cost because the new main was not a like-for-like replacement. It would also mean finding enough space in the congested ground for a large new pipe to be placed. The project team were able to use the CAD model they’d built up from previous sweeps, electronic tracing, ground probing radar and trial hole surveys to prove to the supplier, Southern Gas Networks, that there was enough space in the ground to carry out the work.

 

Example 3 – 36” Water main protection in St Thomas Street

Early on in the redevelopment and as part of a Transport and Works Act order, the project team had to carry out an impact assessment on behalf of Thames Water due to the proximity of the station’s piling works to the Thames Water’s Hampton Main, a massive water pipe servicing a significant area. There were major concerns that the large, old cast iron pipe was vulnerable and potentially susceptible to failure. The remedy was to reinforce the pipe.

If this wasn’t done and the high-pressure main should fail, the potential for flooding, the loss of water supply to a large area, the damage to the road itself and the reputational fallout was deemed to be serious enough to warrant the extra protection. The cost would be accepted by the project.

The 350 metres of 36” cast iron pipe had to be reinforced using a 900mm stainless steel liner which was inserted into the existing pipe at regular points along its length. Water services were diverted during the works to preserve supply to the local area.

 

 

Example 4 – Hostile vehicle mitigation bollards

 

Towards the end of the London Bridge redevelopment works, new legislation regarding vehicle protection for public spaces was brought in. This meant that hostile vehicle mitigation bollards would need to be installed across the front of all the station’s entrances. The licence to open would not be granted until this was complete.

The bollards would require heavy duty foundations in order to withstand a 50mph vehicle strike. Unfortunately, space in the ground was already at a premium due to the high number of existing services.

Although it was agreed that there was room to move the electricity cables, the bollards would still cause major long-term maintenance implications

and restrict access to the other statutory utility services. To reduce the impact as much as possible, a system of bollards was chosen that were inter-connected beneath the ground giving them greater strength and meaning that the excavations could be shallower. The hostile vehicle mitigation system could also be temporarily disconnected in sections to allow individual bollards to be removed. This would provide access to the services below should it ever be required for maintenance.

Example 5 – Authority to cease tenant supplies

The project team at the Bermondsey Dive Under (BDU) part of the Thameslink Programme, ran into an unexpected utilities challenge. Every arch of the old brick viaduct which was to be demolished had housed a different tenant. During the compulsory purchase stage of the project, the tenants had moved out, many not concerned whether the power was still live or not, consequently many of the arches were left with live electricity services that needed disconnecting. However, when the project team approached the electricity company, they were told that as they were not the customer, they had no authority to request another person’s supply to be turned off. At this stage the arches were empty and waiting for demolition. It seemed unnecessarily difficult to get the power company to understand the tenant’s authority could not be given and the situation was not the project’s fault. After protracted negotiations and several site visits the task was accomplished. A lesson for all is about what you say to the electricity company, if you make them aware a service is redundant, they will make it safe. If you ask them to come and take the meter away, effectively the same task, you have commissioned a chargeable piece of work. The financial benefits available made us careful in our approach!

 

Example 6 – Use of un-metered supplies

When a utility company has switched off a metred connection, that pipe or cable is strictly out of bounds and must not be used. With a live service on site there is a serious temptation to use that service as a builder’s supply. This can have serious consequences in the form of financial penalties, particularly when the use of un-metered supplies is by a business.

For this reason, the London Bridge project team went to great lengths to ensure operatives understood the rules and did not connect to supplies that were considered out of service.