Storm water poured off the parking lot and gushed downhill making it a major source of runoff into Reeves Run and Four Mile Run on July 8, 2019. The rain created a huge pool of water and a small river coming out of the drain pipe at the top of the hill. Water was flowing over Livingston Street. The runoff will increase when the parking lot is expanded. It is doubtful the new cistern NOVA Parks plans to construct will hold water from heavy storms so the runoff will continue to increase. Eventually such floods could undermine Livingston Street.
Unusual rain storms will become more usual. The New York Times reported on July 6 about increased flooding in Nashville that, “We’re starting to see evidence that the number of extreme events will increase,” said Barbara Mayes Boustead, a climate scientist and an author of the latest installment of the National Climate Assessment, a report written by 13 federal agencies that explores both the current and future impacts of climate change. An area’s average annual rainfall might increase by what seems to be a relatively small amount — from 40 inches a year to 42, for example — and “in your head, you might say ‘big whoop,’” she said. “But how it falls is the critical piece of the story,” with the extra amount concentrated in extreme events. On July 8 we all saw what a difference some additional inches received all at once rather than averaged over a year make.
The County permitting process created a new water outflow measurement point. NOVA Parks originally positioned it east of Livingston street. It would have measured the runoff from the entire Upton Hill area for the part of the watershed that drains that direction, making it harder to monitor the point discharge from the expanded parking lot. The County staff had NOVA Parks create a new measurement point at the new discharge pipe next to the parking lot (which is more or less at the current outflow point) making it much easier to determine the expanded parking lots impact on water runoff over existing conditions.