Phase one of the CRMP, which was completed in 2021, identified a gap in rainfall flood data across the commonwealth. Fulfilling this need was a top priority for phase two of the plan. In support of these efforts, Dewberry produced rainfall flood models for approximately 15,000 square miles across Virginia’s 57 coastal counties and cities, creating the first comprehensive look at the region’s exposure to existing and future rainfall-based flooding. The team also developed a cloud-based modeling pipeline that assisted the engineers by automating the creation and computation of rainfall flooding in nearly 2,000 two-dimensional watershed models. The final modeling was delivered in an aggressive four-month timeline and consisted of nearly 300,000 simulations of current and future rainfall events in urban, suburban, and rural communities. To enable future model reuse and upgrades, the models were made available online, along with a detailed user guide.

“In phase one of the CRMP, our stakeholders across all eight planning district committees noted that pluvial flooding is their primary flood hazard of concern, largely noting the lack of flood hazard exposure data,” says Virginia DCR’s Office of Resilience Planning Program Manager Matt Dalon, PE. “Dewberry met this challenge head on and developed a robust approach to deliver state of the industry products for public consumption.”

“Mapping information to understand the widespread extent and risks of rainfall flooding has been a long-outstanding need in Virginia and across the country,” says Dewberry Associate Vice President Brian K. Batten, Ph.D., CFM, and Dewberry Project Manager Stu Geiger, CFM. “We were excited to leverage our expertise in flood mapping and technology solutions to meet this critical need and provide data that delivers widespread value to the commonwealth, local communities, and practitioners who seek to build more resilient communities.”

“Dewberry’s pluvial modeling initiative for the Virginia CRMP represents a landmark achievement water resources engineering. By designing and executing one of the largest rainfall-driven flood modeling efforts ever undertaken, the Dewberry team transformed how Virginia understands and prepares for flooding beyond traditional riverine and coastal hazards,” says Virginia ACEC’s 2026 Emeritus Judging Panel Representative Chris Stone, PE, F.NSPE, F.ASCE, LEED AP. “This work not only closes a critical hazard information gap but also empowers communities to make smarter infrastructure investments, enhance emergency preparedness, and protect lives and property in an era of increasingly intense storms. It is an extraordinary example of engineering ingenuity applied directly to safeguarding the public and strengthening long-term resilience across the commonwealth.”