Where we are:
The initial feasibility work by AECOM does not look at the capacity of existing networks
The Great Eastern Mainline will reach capacity, without the Garden Communities by 2031
Atkins have carried out a study showing how it can be increased as part of the SE RUS
Greater Anglias, Anglia Route Study says Liverpool Street will need additional platform capacity in Control Period 6 (CP6, 2019-2024), alongside signalling headway reductions between Chelmsford and Liverpool Street, construction of a new passing loop north of Witham, and track doubling at Trowse swing bridge.
Should ETCS Level 3 be adopted with Automatic Train Operation – assuming the world-first implementation of this technology on the central section of the Thameslink route proves successful – then capacity from Chelmsford to Liverpool Street could increase from the current maximum of 24 trains per hour (tph) to 32tph.
A back of the envelope calculation shows that the line as a whole with a 50% capacity increase (this is simplistic as there is existing commuter growth – though much of it would be displaced from people already living in teh area moving to new communities) could cope with an extra 84,000 commuters per day, so assuming 50% modal share and 2.1 persons per household thats a maximum community size of 88,000 for each of the four communities – much more than planned. So its doable.
What is needed is a joined up approach whereby the capacity of the GEML is looked at in detail alongside the masterplanning of the capacity and phasing of the North Essex communities
Step forward IPC?