What are my tenants doing with the water?

[Jim Workman]

I have two identical 6-unit buildings on the same lot, but they get separate utility bills. One of the units consistantly gets water bills more than double the other building.  I found that the Kansas City Water Dept has a graph of the last 90 days' usage. 

If the links below work, you will need to click on 90 days and click on gallons:

Building 1
Building 2

My first surprise came when I looked at the lower-usage building.  The minimum usage is about 75 gal/day. However, about once a month, the usage shoots over 1000 gals. The average there is about 200 g/day, but since the end of November, usage has increased significantly.

The high-usage unit has a minimum of 75 gal/day with an average of about 400 g/day and more spikes over 1000 gals. However, since the end of November, its usage seems to have gone down.

The gas bill has been similarly higher in this building. I believe the gas only covers the hot water and heating the common areas. Last March, this building's gas bill was $725 vs $250 for the other building.

My property manager has checked for leaks, but the daily swings make leaks unlikely.

The 3rd party coin-op laundry in the basement is usually broken so I'm thinking some the spikes could be due to washing in the sink or bathtub.  I'm also wondering if someone is running hot water to heat his apartment.

Has anyone had experiences with tenants wasting water to this degree? Do you have other ideas as to what is going on?  Money laundering:)

I'm also open to suggestions as to corrections.