Get the flow rate in cubic meters per second. If the data is in cubic meters per minute or cubic meters per hour, divide by 60 and 3,600 -- 60 * 60 -- respectively to get the cubic meters per second flow rate. For example, if 1,200 cubic meters of water flows through a canal per minute, then the flow rate is 20 cubic meters per second -- 1,200/60 = 20.
Find the conversion factor from cubic meters per second to cubic feet per second. There are numerous online sources for this information. Use 35.315 as the conversion factor.
Calculate the flow rate in cubic feet per second. Multiply the flow rate in meters per second by the conversion rate to get the flow rate in cubic feet per second. To conclude the example, the flow rate in the canal is about 706.3 cubic feet per second -- 20 * 35.315.