I wonder if I ran water to my neighbors if my water meter would spin backwards? 1,393,450 gallons of water used since 1980 when I first put in my water system. 92,900 gallons per year usage for an average of 7,740 gallons per month. The average American family of four uses 400 gallons of water per day. On average, approximately 70 percent of that water is used indoors, with the bathroom being the largest consumer (a toilet alone can use 27 percent!). So my 7,740 gallons per month compares favorably with the average American's 12,000 gallons per month. I also have a pretty good sized swimming pool. All this assumes there is no decimal point before that last zero on the meter!