It seems that no one has ...

It seems that no one has responded to your query. But let me tell you that cleaning the Ganga is a humongous task.

The way the Indian Government is approaching the matter, I doubt it would get cleaned. There are several issues with pollution of the river and it is not possible to spell out the issues in this thread. 

I am aware about the Indo German collaboration, but have no idea about how the matter has progressed. It is very difficult to address a matter of this nature at the Central Government level as the river passes through 4-5 states. Maintenance of the river is a state subject and except for 1 state where the government in power is not the same at the Centre, there has been very little progress in the other states where the government is the same at the state and Centre. 

There are several issues with the cleaning up of the Ganga and while installation of STP (Sewage Treatment Plants) are taking place there is shortage of funds for their operations and maintenance. 

Besides this several drains carry sewage to the river and not all sewage is treated. The Central Government has not worked on a realistic budget in terms of the CAPEX for the new plants. 

Information is very sketchy as there is no single agency that has all the information. If someone wants information he has to run from pillar to post to get the information. Most of the time the information is with the water resources ministry of the state. Besides this CPCB (Central Pollution Control Board) has information, but you need to reach the right person to get the information.