Just for you to know what type of power you may harvest
8 feet = 2.4 meter
Power available 2.4 * 6 = 14.4 watts/liter of water volume.
So if you have, lets say 1587 gallon/minute = 100 liter/sec
the power will be 14.4 * 100 = 1440 watts
Therefore if you have 15870 gallon/minute = 1000 l/sec = 1 M^3/sec
The generated power = 14.4 KW
I wonder how much is the cost of producing 1 KWh of energy in your area ( hydro or thermal), I may presume around 0.03 cents.
so 14.4 kwh* 0.03 $/kwh = 0.432 dollars is the production cost each hour the hydro works generating 14.4 kw, for $3784 dollars production in one year.
Regards
Nando