Odana Pond is a wet retention pond, built on an old wetland

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"The Lake Wingra watershed contains eight major wet retention ponds:  the Odana Hills Park pond, the Nakoma Golf Course pond, and six ponds in the UW-Arboretum. Approximately 60% of the watershed’s storm sewers convey runoff to wet retention ponds, which are among the most effective stormwater treatment methods available." "Each pond provides a single, discrete location for removing sediment, pollutants, and nutrients from runoff originating from a broad, diffuse area."