▁February ▁ 1 9 9 8 , ▁the ▁central ▁pill ar ▁that ▁had ▁supported ▁the ▁east bound ▁bridge ▁was ▁blow n ▁up ▁with ▁ 2 0 0 ▁tons ▁of ▁dynam ite , ▁and ▁during ▁the ▁next ▁few ▁days ▁the ▁surv iving ▁arch es ▁from ▁the ▁end ▁sections ▁of ▁old ▁ 1 8 4 1 ▁bridge ▁were ▁also ▁blow n ▁up . ▁ ▁In ▁March ▁ 1 9 9 8 ▁work ▁started ▁on ▁the ▁new ▁central ▁concrete ▁pill ar ▁which ▁would ▁support ▁the ▁new ▁tw in ▁track ▁bridge , ▁and ▁on ▁the ▁new ▁ab ut ment ▁at ▁the ▁northern ▁end . ▁The ▁ ▁steel ▁tr uss ▁bridge ▁structure ▁from ▁the ▁northern ▁end ▁to ▁the ▁central ▁pill ar ▁was ▁then ▁assemble d ▁and ▁mounted . ▁In ▁Aut umn / W inter ▁ 1 9 9 8 / 9 9 ▁the ▁southern ▁ab ut ment ▁was ▁constructed : ▁the ▁southern ▁ 1 0 0   m ▁long ▁tr uss ▁bridge ▁was ▁mounted , ▁and ▁a ▁concrete ▁sl ab ▁was ▁placed ▁over ▁the ▁steel ▁structure ▁to ▁accommod ate ▁the ▁rail ▁tracks . ▁During ▁the ▁summer ▁of ▁ 1 9 9 9 ▁a ▁single ▁track ▁was ▁initially ▁laid ▁on ▁one ▁side ▁of ▁the ▁new ▁bridge . ▁The ▁remaining ▁west bound ▁bridge ▁was ▁now ▁closed ▁and ▁the ▁track ▁removed ▁from ▁it , ▁to ▁be ▁relay ed ▁on ▁the ▁other ▁side ▁of ▁the ▁new ▁bridge . ▁The ▁new ▁bridge ▁was ▁commission ed ▁in ▁July / August ▁ 1 9 9 9 ▁after ▁which ▁the ▁second ▁of ▁the ▁ 1 9