Almost half a billion gallons of urban runoff swamps the UW-Madison Arboretum every year, endangering the restored prairies, savannas and wetlands and gradually overwhelming the stormwater detention ponds that protect the valuable property from erosion.
Five of the six stormwater detention ponds within the 1,260-acre research, conservation, educational and recreational facility have failed, and a concrete gutter that carried stormwater collapsed. As a result, soil has eroded, wetlands have been degraded, and a delta of sediment is settling into Lake Wingra, said David Liebl, the head of a committee that has planned stormwater control improvements at the Arboretum.
Five major projects are planned to help solve the problem over a five-year period, at a cost of $750,000 to $1 million each.