Thanks for more wonderful pictures. If you don't mind I'd like to put a link to your album in the Ordsall Chord thread and one on Skyscrapercity.
Whist not knowing for sure the purpose of particular bits of the work, I can at least partially confirm something you ask in one of the captions. Although the Ordsall Chord will diverge to the
right from the existing viaduct at Castlefield, as seen by the driver of a train from Piccadilly to Liverpool, the existing viaduct is to be widened on the
left in the vicinity of the point of divergence, thus straightening a kink in the track between Deansgate and Ordsall Lane.
I think you may be using the term Zigzag Bridge differently from the official documents. The bridge over the Irwell that once carried a road (Hampson Street) and more recently carried pedestrians and cyclists, and presents a zigzag pattern of white diagonal bracing when viewed along the river, is nevertheless not the Zigzag Bridge, but Princes Bridge. The term Zigzag Viaduct, as used in the documents, refers to the nearby brick viaduct, the edge of which is zigzag when seen in plan. Something of this zigzag can be seen on Google Streetview:
https://www.google.co.uk/maps/@53.4...4!1skd9VqayFVnVCVoPCnbCAQQ!2e0!7i13312!8i6656
