Francesca Holland
Kilvert Street Flooding Redesign
Landscape Architecture for RISD Hydrologic Systems Course
Project Duration: 1 Month, Commitment: Part-Time, Year: 2025
Background:
​Every time it rains at a newly built townhouse complex in Rhode Island, the street has significant flooding that is dangerous for drivers and pedestrians, damages the roadway and creates erosion on the property. The housing complex is surrounded by industrial parks and truck traffic which can create water quality issues in the runoff. There are two storm drains opposite the complex on Kilvert Street, but they are unable to
handle all the flooding when it rains.
Recommended Solution:​​​
I propose installing a planted bioswale along the east side of the road to redirect runoff westward, then south into the housing complex's nearest detention basin. This would involve cutting the existing berm and relocating it 6 ft farther from the road. The bioswale would both direct flow and improve water quality by filtering contaminants.
Because this street currently has no sidewalk and is unsafe for pedestrians even when dry, I also propose adding a porous-paver sidewalk. Beneath the sidewalk, drainage cuts would allow street runoff to enter the bioswale.
Below is a to‑scale section diagram of my design. The dimensions of the bioswale and sidewalk fully comply with the Rhode Island Stormwater Design and Installation Standards Manual and Rhode Island Department of Transportation regulations. That manual will also guide future planting plans for the bioswale, berm, and detention basin.​​​
Site Evaluation:​​
​See below for my annotated aerial image of the complex. This complex was built so recently that Google/Apple Maps do not have updated imagery of it, so new infrastructure has been noted. ​
There is a natural depression in the contours of the street where the flooding pools up on the side of the road next to the east side of the complex. See below for a version of the map with the contour lines and a measurement of the drainage area of the street.
Aerial Rendering of Recommended Solution:​
Retention Basin Closest to Flooding:
Does not reach close to capacity during typical rainfall
Flooding analysis and landscape measurements were carried out during on-site visits
Calculations:​​
​In order to determine the capacity required for the new bioswale and its connection to the detention basin, I carried out the following Water Quality Volume and Capacity Calculations.
