The bucket method measures flow rate by recording the time needed to fill a container of known volume. Dividing the bucket volume by the fill time (converted to hours) yields the flow rate in gallons per hour, which is then multiplied by the annual operating hours to obtain total annual water consumption.

\begin{equation}\label{eq:water-reduction-bucket} W_{use} = \frac{V_{bucket} \cdot 3600}{t_{fill}} \cdot t_{op}\end{equation}

Symbols

\(W_{use}\)	Annual water use \([\unit{ \gallon\per\year}]\)
\(V_{bucket}\)	Volume of the bucket used for measurement \([\unit{ \gallon}]\)
\(t_{fill}\)	Time to fill the bucket \([\unit{ \second}]\)
\(3600\)	Conversion factor from seconds to hours \([\unit{ \second\per\hour}]\)
\(t_{op}\)	Annual operating hours \([\unit{ \hour\per\year}]\)