Submeter water

[Ron Steele]

I have an apartment building that has been individually Submetered already that I currently pay utilities on. 

I want to shift the obligation to the tenant. The current lease does not specify that I pay the water, but I think it's ethical to honor this arrangement during the duration of the current lease.

Or should I send out a letter in the next 30-60 days to state the change. What are the laws in regards to this? 

Lastly, I have another apartment building that is not Submetered. Would it be better to add a water reduction plan or get the building sub metered. Or maybe a RUBS program?

Thanks in advanced.