This (near the Peahen Junction) has been a problem for some time but we are told that Herts Highways is fully aware of it and that Veolia has it on their list.

The note below from Veolia should explain further:

Veolia Water plan to undertake mains diversion works at the above junction from this Sunday (22nd) until Tuesday (24th). The diversion works will hopefully solve ongoing issues Veolia have had with leaks on the existing water main that crosses this busy 4 way signalised junction.

Veolia propose to complete a new road crossing of London Road about 100m back from the junction and abandon the existing road crossing. The individual service pipes that were fed from the abandoned main will then be transferred onto the newly laid section.

Veolia expect the new road crossing to be completed on Sunday with the service transfers taking place Monday/Tuesday. The works will require the existing permanent 4 way signals to be switched off and replaced by a temporary 4 way setup.

These network critical works have been planned for the coming weekend to avoid any clash with the resurfacing of A4147 Folly Lane/Catherine Street,that should be complete by this coming Friday. As well as the planned resurfacing of King Harry Lane that is due to commence on Monday 6th
September.