Southern Gas Networks (SGN) have a 15 year plan of gas pipe replacement for Southwark. This is a hugely disruptive programme – Borough High Street, Denmark Hill, Lordship Lane, and Freirn Road – huge traffic congestion for months on end. In the case of Friern Road plans for 15 months work.

Picture to the left is Denmark Hill after two weeks of single lane 3-way traffic lights operation. Still obviously lots of work to be done at this rate.

But is it necessary?

Undoubtedlygas is leaking in tiny amounts from the 100yr+ cast iron pipes across Southwark and replacing them is the UK’s current solution. Natural gas or methane is 20 times worse than Carbon Dioxide as a global warming contributor.

But what if  leaks could be fixed without massive.y disruptive pipe replacement?

In the US a start up company called Picarro has developed a laser-based device (cavity ring-down spectrometer) that can take rapid measurements of gas concentrations down to the parts per billion level.  Its a car based system and can quickly survey a city as they’ve done for San Francisco and Boston already taking  just a couple of days.

Once you know where any leaks are occurring you can fix them, just them, and not need to replace the whole pipe.

Apparently cast iron pipes were sealed with jute which dries our over time allowing leaks. 

 A robot (CISBOT)  has been used to fix thousands of such joints in New York City alone. Currently is has to be inserted every 150m. These fixes can also take place while the gas pipes are kept operational making it much simpler to just get on with it.

So the next time you’re stuck in traffic and can see people working on huge yellow plastic pipes remember they could be working a lot smarter sensing gas leaks and using robots to just fix leaks and not replace whole pipes. They’d also be nearly halving their costs and take a fraction of the time.