Elevated railway tracks

One of the reasons for severe traffic congestion in Dhaka is railway gates. It seems that trains leave and arrive Dhaka station almost every few minutes. Once a railway gate is closed, traffic backs up quite a bit, before a backlog is cleared, it is time for another train to pass.
I wonder why there is no plan for building elevated railway tracks between Dhaka and Tongi. It does not need any new land acquisition, should be easy technology, can be done by Bangladeshi expertise, should be able to complete very quickly.