To prevent the pump from cavitating
To prevent the pump from running when no water is available.
To prevent backflow
The pump capacity, efficiency, and horsepower.
The pump rate, efficiency and head
The pump rate, and system pressure
Lead pipes, and solder used in pluming
Corrosion within the distribution system and residential plumbing
Natural lead content leaching into the water system
Improper treatment of water
The reaction of chlorine compounds and organic material
Crop treatment run off into the water supply
Prescription drugs from waste water disposal.
Free and total
Hypochlorous acid (HOCI) and hypochlorite ion (OCI-)
Hydrocloric acid (HCI) and hypocloric acid (HCO)
Graduated cylendar settling test and turbidity tests.
Perform a series of jar tests.
By monitoring the end product water quality.
Sludge sample test
Here's an interesting quiz for you.