In 2008, the Eastern Region Line (ERL) was announced for projected completion in 2020. Since then, the Land Transport Authority has found planning the line challenging. Part of this stems from having to plot the line parallel to the old sea wall before reclamation works began. As there are no detailed records, this proves to be an uphill task of ensuring that areas where the line runs through are suitable and will not suffer from soil displacement once construction work begins (a very visible effect in similar ground conditions is the 2004 Nicoll Highway collapse). As such, it is not surprising that the line will only see completion after 2020. So what is the probable timeline for the line then?
Going by past instances, notably for Downtown Line Stage 3 (DTL3) and the Thomson Line (TSL), announcement of station locations were done at ministerial inspections of under construction stations. The same can be assumed for the ERL. Probability points to either the North South Line extension to Marina South Pier (due 2014) or the Downtown Line Stage 2 (DTL2 - due 2016). Substantial work is completed on both projects, with Cashew station on the DTL2 at advanced structural works. So potentially, there will be an announcement of the ERL station locations in 2014.
Again, referring to past instances, DTL3 was announced August 2010 and groundbreaking was in end-November 2011, roughly a period of 1 year till construction. Similarly, TSL was announced in August 2012 and construction slated to begin end-2013 or beginning-2014. We can expect ERL construction to begin at roughly end-2015 or even beginning-2016 which is in time for the DTL2 crew to shift over with the resources.
The average time to build an underground line is about 6 years. The North East Line (NEL) took 7 years to complete, Circle Line took a whopping 10 years (due to various delays and accidents), Downtown Line 1 is taking 6 years. Thus, we can expect the completion of the ERL about 2022 to 2023 or 2024.