Daily Variations:

The maximum daily rate may be estimated at about 150% of the average. For the larger cities, the ratio of 150% is seldom exceeded but for the smaller cities the ratio is frequently above 200%. The larger the average consumption, the greater the variation. The maximum daily rate usually occurs in the month of maximum consumption. Thus, where the maximum daily consumption is 150% of the average, the maximum weekly consumption is likely to be about 130% of the average but for longer period of time, the rate will approach the monthly maximum.

Hourly Variations:

Hourly variations are very important as they have a very wide range. During active household working hours in the morning around 6 a.m. to 10 a.m., and 4 p.m. to 8 p.m. in the evening, the bulk of water is consumed, especially, within the morning hours. During late hours in night demand is almost negligible. If a fire brakes out, a large quantity of water is required to be delivered during a short duration and this may necessitate maximum rate of hourly supply. To accommodate all these fluctuation, service reservoirs, a supply pipes, and distributing pipes must be properly sized.