you have many tools in gromacs: g(r), sasa, etc...Best,

I am not sure if it is compatible with Gromacs or not but you can try 3D RISM which uses statistical mechanics and water distribution can be analyzed. 

Thanks

Hello XW Ou, 

What is Xdrfile and how does it relate to analysing solvation of proteins?

Thanks.

 Hi, 

Please have a look at this list;

http://manual.gromacs.org/programs/byname.html

There are multiple tools, including gmx trjorder, gmx h2order, along with already mentioned by Philippe.

Hope this will help.

g_hbond could be particularly relevant in your case. You can run it and then either use its own utilities or write custom scripts to obtain the desired statistics.

(E.g., you can obtain a matrix of h-bond existence for each donor-acceptor pair that is h-bonded in your trajectory.)