VIRGINIA BEACH — Dewberry, the professional services firm hired by the city to research sea-level rise here, recently unveiled the first piece of its comprehensive report to City Council.
The city hired Dewberry in 2015 to chart the threats posed to Virginia Beach by rising sea levels and recurrent flooding.
The study is intended to inform the city’s decisions on how to defend itself against sea-level rise and recurrent flooding through the 21st century.
The study provided different combinations of structures the city could construct to combat sea level rise, with estimated costs varying between $1.71 billion to $3.79 billion — money that, if allocated for projects, would be dedicated over a series of decades.
Brian Batten, the senior coastal scientist and project manager at Dewberry, presented the first briefing last Tuesday to City Council on the report.
“The trend of relative sea level increase is projected to accelerate through the end of the century,” Batten said. “This report is meant to provide some tools for how to buy down risk in areas of the city that are likely to be flood-prone in the future.”
Observational data compiled by Virginia Institute of Marine Sciences points to a 1.6-foot rise in sea-level around Virginia Beach by 2050. The projections sourced were from federal entities to establish planning values for Hampton Roads as an aspect of VIMS Recurrent Flooding Study for the Virginia General Assembly in 2013.
A multitude of approaches to sea level rise in Virginia Beach — including flood gates, seawalls, and green measures — were discussed by representatives from Dewberry and city staff in the creation of the study.
The report offered several infrastructure possibilities to alleviate frequent flooding. One such scenario, near Muddy Creek Bridge in Pungo, called for raising the bridge and constructing a flood gate that would separate parts of Beggar’s Bridge Creek and mitigate flooding over the road.
If the city does nothing to combat sea level rise, by 2050 there will be annualized economic losses of $50 million — about four times the current level, according to the report.
“Moving out towards the end of the century, we hit kind of a tipping point in the topography of the city and its building stock and we see about a 23 times increase” in annualized losses — equivalent to $271 million, Batten said.
The Dewberry report notes changes at the state and federal level “have the potential to create additional funding streams for sea level rise and flooding mitigation.”
The Jan. 15 briefing was only a portion of the full report, as city leaders acknowledged it would be best to review the report and its contents little by little.
“You can’t eat all this in one bite because there’s a lot to learn and a lot to discuss before we can raise our hands and say ‘this is how we want to proceed,'” City Manager Dave Hansen said.
More information is available on the city’s response to sea-level rise. A full-version of the Dewberry’s briefing on sea level rise is also available.