DELAWARE — Delaware residents won’t soon forget the sheets of rain that fell in mid-August — or the flooding that followed.
It wasn’t the first major storm to send water spilling into neighborhoods from Clear Run, retention basins and ponds, but it was among the worst in recent memory.
Now, city officials are proposing a $25,000 stormwater study to better understand flooding in northwest Delaware, particularly around the Addison Farms development, and identify potential solutions.
City Engineer Jonathan Owen presented the proposal to Delaware City Council on Monday. The study would be conducted by EMH&T, an independent engineering firm, and comes amid concerns about public trust in previous assessments of the area’s drainage.
Following the August flooding, Owen and former City Manager Paul Brake proposed bringing in an independent engineering firm to evaluate the area, citing the sensitivity of the issue and a “potential lack of trust” in the Addison Farms developer, its engineering consultant and the city’s own engineering reviews, according to the legislation’s fact sheet.
Council did not pass the legislation on Monday, but will discuss it again at their Nov. 23 meeting.
More on how the ordinance came to be
The storm from 2024, and this past August’s storm, served as a base for the ordinance’s discussion.
“A stream [Clear Run] that runs west-east across the Addison Farms development near just north of Sylvan Drive overtopped its banks [in August], and a resident reported flooding through a rear walk-out basement located near the stream,” the city facts sheet states.
“Residents in the area have expressed concerns to council and staff that the risk of flooding/stormwater drainage issues have increased due to the ongoing Addison Farms development, and that the development was a contributing factor to the stream overtopping its banks and entering a basement.”
The facts sheet adds that shortly after crews constructed stormwater infrastructure at Addison Farms in 2024, residents raised similar concerns because two of the development’s basins lead into the nearby stream.
At the time, city engineering staff reviewed the previously approved stormwater management plans and calculations for Addison Farms and determined they met the city’s design requirements for how quickly water is released from the development’s retention basins, according to the fact sheet.
The ordinance’s full facts sheet is attached below. Story continues below the facts sheet.
Council discusses further
Owen explained that the drainage area sending runoff into the nearby stream covers about 79 acres, but 58 of those acres lie outside the Addison Farms development.
“I am concerned a little bit about precedent; this was not the only area in the city that had flooding on that specific rainfall event [in August 2026],” Owen said.
“I would be a little concerned if we had an expectation going forward that we were going to spend this kind of money on an independent evaluation after each time we had a heavy rainfall event where streams and rivers rose and perhaps got onto somebody’s property.”
Councilwoman Linsey Griffith pushed back on the way the ordinance was presented.
“It’s being presented that this is a concern over one resident’s basement; that is not the issue,” Griffith said.
Griffith said Ward 1 residents repeatedly raised concerns during the Addison Farms approval process about plans to remove three wetlands without adequately addressing how the additional runoff would affect the city’s stormwater system and nearby river.
She also pointed out that 60 acres of trees were removed for the housing development and that one tree, on average, accumulates 3,000 gallons of water during a rainfall.
“Then, we expected three small retention ponds to be able to handle that amount of water [the trees would have accounted for], plus three small wetlands worth of water,” Griffith said.
“This [past August’s storm] wasn’t a one-off event. This was not a 100-year flood, this was what’s going to be a five- or six-year rainfall.”
Additionally, Griffith explained how the retention basins sit, elevation-wise, above where residents’ homes are. She argued those individuals should not have to “bear the brunt of a developer’s impact,” with some of those homeowners living in the area for more than 20 years.
“We fought this when it was proposed, I fought it two years ago when we saw it as it was constructed and now we’re fighting it again,” she said.
“We saw it coming, we came to council, we warned you it would happen and then, once it was constructed, oh look — it indeed happened, exactly as we warned you it’d happen.”
Griffith said she didn’t want tax dollars to pay for the study. But when an issue affects an entire neighborhood, she said residents paying for a developer’s “consequences” is a dangerous precedent to set and called for the independent study to happen.
Before council decided not to take action, Vice Mayor Caitlin Frazier said should the study occur, the results need to be properly communicated to the public as the city does have its own engineering department.
