St. Stephen's Green To Become A Huge Construction Site. CIE, on behalf of Irish Rail, have applied for a railway order for the planned Dart Underground under Dublin City Centre. Unfortunately this is going to have a huge impact on St. Stephen's Green. According to some reports at least a quarter of the park will be devastated by the scheme. For an extended period the public space will be turned into a vast construction site, requiring the removal of the landmark Fusiliers' Arch at its northwestern corner, dozens of mature trees and a large part of the lake.