Water is being moved from the dam inside Walnut Creek. The work started on Sunday as the storm was still organizing.
The water level has dropped by more than a foot, which comes out to approximately 40 million gallons of water. The water level will rise again once Debby arrives and brings heavy rainfall.
"Every gallon that we can capture there (in Lake Johnson's dam) and hold is one less gallon that moves downstream," said Raleigh Stormwater Senior Engineer Scott Bryant.
He says even with these efforts, there could still be extensive flooding.
"It depends on how much rain we get, which the numbers are increasing. So this will certainly hold some and help some. But at a point, if we get so much rainfall, that's why we encourage the awareness of knowing where floodplains are, avoiding low-lying areas, never ever drive through or try to move through flooded areas because you never know what conditions are there," said Bryant.
There are a lot of homes and apartment complexes located along Walnut Creek.
Buildings at Brook Hill Townhouses sit yards away from the creek and there are signs dotting the property warning the area is in a flood zone.
One man, who didn't want to share his identity, showed ABC111 an email that management sent about Debby.
Those who live near the lake are being put on notice of potential flooding. They are strongly encouraged to relocate "any valuable items and furniture upstairs" and also park vehicles in higher, elevated locations.
Tenants are heeding the warning and moving furniture upstairs to the second floor ahead of the storm.
He said, "I sort of expected moving into a place that is a flood zone. Rent was cheaper, so it is what it is."
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