Benefits of riverfront development still outweigh flood risks, Danville officials say

Danville did not experience the same severe floods in the wake of Hurricane Helene that communities across parts of Southwest Virginia are still feeling the effects of.

Still, flooding is a frequent topic of discussion among city leaders as Danville works to capitalize on the Dan River for recreation and economic development purposes more than ever before.

Existing and anticipated riverfront projects — apartment complexes, parks and other recreational facilities — are designed to withstand flooding, said Ken Gillie, Danville’s director of community development.

But no matter how prepared you are, “Mother Nature is an amazing thing,” he said.

“Sometimes there are things you can’t prepare for,” Gillie said. “It is a cause for concern, but it’s not a deterrent” to riverfront development.

Previous severe flooding in Danville, caused by storms like Michael in 2018 and Fran in 1996, have better informed the city about how to prepare for these events, he said.

Gillie is a certified floodplain manager with the Virginia Floodplain Management Association, and part of his job is to reduce the risk of flooding in the city, especially around riverfront developments — which have been increasing in number in recent years.

The Dan River runs for about 11 miles through the city. Historically, the river was primarily used for industrial and commercial purposes. The city did not capitalize on its riverfront property for economic development, quality of life or recreation until recently.

When the Danville Family YMCA was built in 2014, it was the first building constructed to face the river in more than 100 years.

Today, a handful of riverfront projects are under construction, including a riverfront park and a mixed-use development called Dan River Falls, formerly known as the White Mill, which will feature both residential and commercial uses.

A whitewater channel and pedestrian bridge over the river are anticipated future projects, though they have not yet been started.

Rules and regulations

Federal, state and local regulations govern building in floodways and floodplains, terms that have slightly different definitions.

Development is not allowed in a floodway — the channel of a river — unless it brings a net-zero change to the water level, Gillie said.

For development to occur, one of two things must happen: Either a study must show that development will not affect the water level or there must be compensation for that change elsewhere.

Gillie illustrated this concept with an analogy about a finger in a cup of water:

If you fill a glass of water to the brim, and then stick your finger in it, it will overflow. When you take your finger out, there’s extra room in the glass. If you were to put your finger in again, the water would rise back up to the brim but not overflow.

“That’s the same kind of thing that happens wherever development goes in a river,” he said. “Usually, they can go and dig out additional areas or remove material someplace else.”

This was the case earlier this year when a historic low-head dam was removed from the Dan River to allow for construction of an overlook pier that is part of the riverfront park plans.

Because the pier pylons will cause a rise in the water level, something else had to be removed.

Floodway additions sometimes can raise the water level indirectly, too, Gillie said, mentioning a railroad bridge across the Dan River where trapped debris creates a damming effect, especially after storms.

“For the city bridges, we did compensatory excavation in areas so that the studies came back saying there would be no rise [in the water level] from putting the bridges in,” he said.

Development is more readily allowed in a floodplain, the low-lying land adjacent to a river that is susceptible to flooding.

“According to our code, you can either elevate the structure … or you can floodproof the structure,” Gillie said.

A row of former tobacco warehouses that are now mostly apartment buildings line Bridge Street, a road that runs along the river in Danville’s River District. When these buildings were converted into residential and commercial spaces, portions of them were floodproofed, Gillie said.

“The buildings themselves are designed to be flooded, and you can minimize the impacts on the critical systems to the building,” he said. “The air conditioning systems are all elevated on platforms. The sheetrock itself is going to get wet, but they put metal edges on top of it so that the water doesn’t move further up the wall. The electrical outlets are all elevated to be a foot out of the floodplain. The mechanical systems, the roof ducts, the duct work — everything’s ceiling-mounted.”

These development regulations can be adjusted as floodplains change.

Danville’s local floodplain maps are in the process of being updated for the first time since 2010, said Gillie, who has a cabinet full of the maps and other floodplain information stored behind his desk. This process will probably take about another two years.

“[The maps] are our Bible when it comes to what can happen with development,” Gillie said, adding that they’re available online on the city’s GIS website.

Keeping up with changes

Danville has seen significant riverfront development since the last time the flood maps were updated 14 years ago.

Each time a flood occurs, the city learns more about its floodplains, Gillie said.

Fran hit Danville in 1996, the same year that reporting began for the Dan River water level gauge. The river crested at 28.65 feet during that storm, nearly 8 feet above flood stage. This was the highest crest on record until Michael in 2018, when the river crested at 30 feet.

During both storms, trees fell, residents lost power and streets flooded. Damage from Michael cost the city almost $10.7 million.

“Michael is one of the reasons we needed to change the maps,” Gillie said. “We had areas that flooded that weren’t on our maps. … With corrected maps, we’ll be better prepared in the future for stuff like that.”

The last major flood reduction project that Gillie said he can recall was the construction of dikes around the city’s water and wastewater treatment plants in the 1990s. Since then, there has been other smaller-scale work to protect the riverwalk trail from flooding.

The Federal Emergency Management Agency also puts out floodplain maps for different communities, updating them “every so often, depending on what happens in an area,” Gillie said.

‘Built with flooding in mind’

Like the Bridge Street buildings, the riverfront park and Dan River Falls projects are being “built with flooding in mind,” said City Manager Ken Larking.

Bill Sgrinia, Danville’s director of parks and recreation, said that the city worked with engineers and used both documented and anecdotal floodplain information during the planning process for the park, a project that will likely cost between $18 million and $20 million by the time it is finished in early 2025.

“The riverfront park was designed and is being built to flood,” Sgrinia said.

The river bank near the park construction is “armored with materials that will withstand normal high-water events,” he said. These solid materials will allow for easier cleanup when the Dan River waters rise, he added.

“Of course, we can’t predict the size of future floods, but we feel confident we will withstand normal high-water events,” Sgrinia said.

The park’s river access points will be reinforced with natural elements, too, added Graham Smith, president and landscape architect for Site Collaborative, the city’s prime consultant for the park project.

“Along with the boulders we are placing along the river’s edge, we are also incorporating some woody plants and bioengineering techniques to add additional layers of bank protection,” Smith said.

Dan River Falls, an $85 million project that is expected to open later this year, sits right next to the riverfront park and features a parking deck under the first floor of the building. Parking is allowed in a floodplain, Larking said.

“In all the time I’ve been here, I have not known the White Mill to flood,” he said. A large berm, or raised bank, stands between the river and the building, he said.

Danville’s riverwalk, a paved walking trail that runs for more than 11 miles and is a big attraction in the city, is also susceptible to flooding.

The thunderstorms that swept through Danville in the aftermath of  Helene flooded several parts of the riverwalk and caused at least one sinkhole to appear.

A few years ago, significant flooding of the riverwalk prompted the city to move the pavement farther away from the river, Larking said. In one section, the asphalt was replaced with concrete for increased resiliency, he said.

“You try to do better every time something like that happens,” Larking said. “It’s still part of our economic development strategy to capitalize on our river, which is part of our identity and a great natural amenity that people enjoy.”

The potential for flooding won’t make Danville shy away from these riverfront projects, Gillie said.

“People like to be around the water, and we have the tools in place to try to make that as safe as possible,” he said. “We learn from each [flooding] event.”

Still, historical data can only help so much, especially as the climate continues to change, Gillie said.

“You’ll never be able to predict everything,” he said. “But we do the best we can.”

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