Turbine Selection Chart (click to enlarge):
turbine selection chart

Online Tools:
Hydropower Regs & Permitting Info Desktop (RAPID) Toolkit
Ductile Iron Pipe Calculators
HDPE Pipe Calculators
AWWA Flange Torque Calculator
WSU Water Hammer Calculator
Rebar Development Length Calculator
ASCE Calculators and Technical References (requires membership)
Valve Flow Coefficient Conversion
Unit Conversion

The Oldest Recorded Description of the Hydrologic Cycle:

“Behold, God is great, beyond our understanding; the number of his years is uncountable. He evaporates the water, which condenses into rain from his mist. The clouds pour it down on mankind in abundance.”
~Job 36:26-27, c. 1700 BC