A new study shows the proposed Fisher's Cove subdivision in Lewes will likely increase flooding in the surrounding area during a major storm. Other developments, including Lewes Waterfront Preserve and Harbor Point, would cause less disruption, the study shows.

Betsy Hicks of consultant AECOM used five models to simulate flooding conditions in areas surrounding two proposed projects in Lewes – Fisher's Cove, an 18-home community off Rodney Avenue, and Lewes Waterfront Preserve, a 90-unit townhouse community off New Road near the Canary Creek bridge. Also included was Harbor Point, a 69-lot subdivision under construction along the Great Marsh off Park Road near the University of Delaware wind turbine.

Hicks’ models showed increased flooding immediately surrounding Fisher's Cove, likely due to the proposed grading of the project.

Consultant recommendations • Look at entire basin when designing stormwater system • Consider storm surge and rainfall when designing stormwater system, as each plays a big role in flooding • Ensure final grading and stormwater design for projects accommodate surrounding areas and don’t have adverse effects • Include water table effects on stormwater pond design • Monitor and maintain stormwater systems. Remove debris prior to major storm events • Minimize increases to impervious surfaces

“A lot of the homes on the northern side of Rodney Avenue are draining into the Great Marsh via a little ditch that runs behind those homes,” she said.

Proposed grading fills in the ditch, she said.

“Now the homes in that area would have to rely upon the storm drain system to drain the water,” she said. “It’s less efficient, so you’re seeing a little more buildup of water.”

She said it’s possible the projections could change as the Fisher's Cove plan for grading and stormwater management evolves.

Tim Tice with Fisher's Cove developer Burke & Rutecki LLC said the report will be a good tool to better shape the development.

“We look forward to continuing to work with the city engineers, the Board of Public Works and the Sussex Conservation District to put together a final plan,” he said. “The hydrology report will inform that effort, so the information provided in the report is appreciated.”

Overall, Hicks’ models found only a slight increase in flooding throughout the basin – in most cases, an inch increase.

“It’s not huge, but it does indicate a pattern that the area is not an infinite resource that can absorb changes to the land cover and changes to the storm drain pattern,” she said.

Six scenarios combining storms of varying magnitudes, rainfall events and sea-level rise were evaluated – three under present-day conditions without sea-level rise, and three based on future conditions plus 1.33 feet of sea-level rise.

Hicks also ran Lewes Waterfront Preserve through the models and found no significant increase in flooding post development.

“The area upstream is a much larger basin [than Fisher's Cove],” she said. “Because of that, it is able to absorb these changes … without having a noticeable increase in flooding.”

Land use is important, she said.

“A densely vegetated marsh provides more frictional resistance and can slow the flow of water more effectively than a concrete or asphalt surface,” she said.

Other factors taken into consideration include soil characteristics and existing stormwater systems.

To validate the models, Hicks used a storm in January 2016. The flooding results from each model were compared to photographs provided by residents and those that appeared in the Cape Gazette. Hicks said the comparison showed the models were accurate.

Deputy Mayor Fred Beaufait said he found the report useful.

“You validated many things many of us suspected were true,” he said. “With this information, we have a better foundation for making comments and decisions.”

Fisher's Cove hearing delayed Set to conclude Aug. 21 By Nick Roth For the second time in as many months, the Lewes Planning Commission granted a request to recess the public hearing for Fisher's Cove. The hearing is now set for Wednesday, Aug. 21. Developer Burke & Rutecki LLC is proposing to build 18 single-family homes on a 12.06-acre parcel off Rodney Avenue. The property is also bordered by the Great Marsh, University of Delaware property and homes along Pilottown Road. Despite the decision to delay the conclusion of the hearing, the commission allowed the public to speak at its July 23 meeting. “This is a direct threat to our health and well-being, and it’s unnecessary,” said Rodney Avenue resident Janice Pinto. “We believe the purpose of our laws and regulatory procedures is to protect existing citizens of Lewes, not real estate developers and salespeople.” She said the property where Fisher Cove is proposed has been a place for floodwaters to go for many years. “The destruction of this environmentally sensitive flood plain impacts the habitability of the entire city of Lewes,” he said. “We believe we are worth saving, and we need your help. As more land gets covered, the water has no place to go. This is a defining moment in Lewes.” Rodney Avenue resident Steve Krynski suggested the developer be required to post a bond to guarantee the project will not adversely affect the neighbors. “At the end of the day, we’ve all seen a lot of projects that haven’t worked,” he said. “What if this project doesn’t work? Who’s going to stand behind it if I have 6 feet of water in my backyard?” Fourth Street resident Elaine Simmerman urged the planning commission to use the city’s core values in making its decision on the proposal, specifically the core value that reads “Lewes recognizes and maintains its internal communities.” “Rodney and Hornkill are internal communities and have been for much longer than most communities in Lewes,” she said. “Yes, communities change over time, but this is going to be a dramatic change.” She said she’s already spoken to people who have moved or plan to move as a result of the Fisher's Cove application. “I think the study about storm surge and flooding is very important to the decision, but also consider the impact on the fabric of our community,” she said. An attorney representing many residents of Rodney and Hornkill avenues was unable to attend the commission’s June meeting. Commissioners agreed to recess the meeting until July 23. A few days later, the developer’s attorney and engineer indicated their unavailability for the July meeting and requested the hearing be delayed again. The commission again agreed and scheduled the the public hearing for Wednesday, Aug. 21.

This story originally posted 07/29/19 and has been refeatured.