. ▁The ▁project ▁will ▁rel ieve ▁the ▁inner ▁city ▁of ▁tram ▁and ▁car ▁traffic . ▁The ▁urban ▁environment ▁will ▁benefit ▁as ▁a ▁result ▁of ▁the ▁elim ination ▁of ▁the ▁tram ▁tracks ▁in ▁the ▁ped est rian ▁zone ▁and ▁the ▁re building ▁of ▁Kriegs straße . ▁The ▁city ▁will ▁also ▁benefit ▁from ▁the ▁creation ▁of ▁additional ▁capacity ▁in ▁the ▁tram ▁network . ▁ ▁The ▁project ▁is ▁still ▁very ▁controvers ial , ▁which ▁was ▁also ▁reflected ▁in ▁the ▁results ▁of ▁the ▁two ▁previous ▁refer end ums . ▁The ▁high ▁cost ▁and ▁the ▁dis ruption ▁during ▁construction ▁are ▁critic ised ▁in ▁particular . ▁The ▁necessity ▁of ▁the ▁project ▁continues ▁to ▁be ▁question ed ▁and ▁alternative ▁concepts ▁have ▁been ▁proposed ▁in ▁the ▁form ▁of ▁am ended ▁align ments . ▁A ▁citizens ' ▁initi ative ▁against ▁the ▁combined ▁solution ▁was ▁launched ▁in ▁the ▁summer ▁of ▁ 2 0 0 9 ▁to ▁require ▁a ▁third ▁refer endum , ▁but ▁this ▁failed ▁in ▁the ▁administrative ▁court . ▁ ▁The ▁first ▁sod ▁was ▁turned ▁for ▁the ▁construction ▁of ▁Stadt bahn ▁tunnel ▁on ▁ 2 1 ▁January ▁ 2 0 1 0 . ▁The ▁first , ▁prepar atory ▁work ▁had ▁already ▁been ▁carried ▁out ▁in ▁ 2 0 0 9 . ▁The ▁Stadt bahn ▁tunnel ▁was ▁originally ▁expected ▁to ▁be ▁completed ▁by ▁the ▁end ▁of ▁ 2 0 1 6 ; ▁this ▁is ▁now ▁expected ▁at ▁the ▁end ▁of ▁ 2 0 2 0 . ▁The ▁reconst ruction ▁of ▁the ▁Kriegs straße ▁started ▁in ▁ 2 0 1 5 ▁and ▁is ▁expected