| adopted, and slopes determined what was safe and what was not. Mr. |
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| Kaltsounis asked about the slope ratio, and Mr. Mickalich said that it was |
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| a one on six. Mr. Kaltsounis asked how deep it was from the top to the |
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| bottom and how deep it would be if he was standing at the edge. Mr. |
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| Mickalich answered that per Ordinance, the standing water on a normal |
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| day that had to be retained was two-and-a-half feet deep. For the worst |
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| storm in 25 years, the level would be about three-and-a-half feet deep to |
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| the permanent water elevation. Mr. Kaltsounis asked what the typical |
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| water level would be, and Mr. Mickalich advised that it would be 831.50. |
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| The bottom of the basin was at 829, and he reiterated that it would be a |
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| one on six slope, meaning that if someone was in the water, that would be |
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| a comfortable slope to get out of the basin. |
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| Mr. Davis agreed that it was not any different. There was a similar project |
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| under construction currently (he referred to Rochester Meadows on the |
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| south side of Avon, east of Rochester) where they had heard the same |
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| type of concerns from adjacent residents. That basin was constructed |
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| with a detention area and also a forebay area. It had a permanent |
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| standing water level with a minimum of two feet. It was over-excavated to |
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| provide that. He agreed that what Mr. Mickalich had said was correct; per |
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| the City’s Engineering Standards, if there was a one-on-six side slope for |
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| the basin, it was considered a walkable slope and a slope that was flat |
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| enough so that it did not require fencing. When there were steeper side |
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| slopes, the City would allow a basin to be constructed with a one-on-three |
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| slope, but anything steeper than that was not permitted. Between a |
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| one-on-three and a one-on-six, the City would require a basin to be |
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| fenced. If there was a flatter side slope, the basin would take up more |
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| area. Generally, developers would go with that to avoid having to put a |
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| fence around the basin. The proposed design was a result of the City’s |
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| Engineering Standards that were adopted four years ago. It was a |
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| balance to try to encourage sediment not being transferred downstream. |
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| The sediment would settle into the forebay before it hit the detention area |
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| and then exit. To make it safer, it would have to be a dry basin, but the |
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| Oakland County Water Resources Commissioner preferred the |
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| incorporation of forebays and incorporating provisions in basins to |
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| encourage sediment to settle out. |
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