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For the majority of testing, alum dose was set by +equation 18+. After the change of A from 15 to 10 was made this approach was effective for the low turbidities that the flocculator experienced this summer. Hopefully in the future the raw water turbidity will change enabling testing of higher turbidities. Through use of +equation 18+, observing the floc tank and conversations with the operators at the water treatment plant it has become apparent that there is still a lot of research that needs to be done regarding alum dose. Observing the floc tank was helpful in being able to identify different kinds of floc and what different alum doses looked like in the water entering the water treatment plant. The water treatment plant has now switched to a different coagulant but if they had to go back to alum they said they would use past experience and alum doses as well as jar tests to set their doses. This suggests that for each water treatment plant an equation, formula or at least a rule of thumb could be developed off of past water treatment for future dosing. If this formula would be translatable to other water treatment plants and different water types is uncertain. The run increment alum dose test should help to shed light on alum dosing as it allows the alum dose to be changed while at a relatively constant raw water turbidity. Hopefully the data from this test will show either an optimum dose or a small range of optimal doses for specific settled water turbidity.

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