Sewershed OH-003 · NYC DEP Combined Sewer Overflow Tributary Area
OH-003 - Sunset Park, Brooklyn
Properties in this area share the OH-003 combined sewer — during moderate-to-heavy rain, runoff can exceed pipe capacity faster than it drains, which is what drives sewer backup exposure block by block. Here’s what that looks like for Sunset Park, Brooklyn specifically.
OH-003 is a combined sewer area covering 3,000 properties in Sunset Park, Brooklyn. Flood Form rates 19% of them Moderate or High for stormwater exposure, and 18% for groundwater. 80% of lots have yard area that legally qualifies for on-site infiltration. Ground elevation is typically 88 ft. The median building dates to 1910. 7% of parcels sit over a historic stream or pond.
3,000
Properties in sewershed
80.1%
Legally eligible for on-site infiltration
19%
Stormwater exposure: Moderate or High
18%
Groundwater exposure: Moderate or High
What sets OH-003 apart
88 ft
Median ground elevation
84%
Average impervious cover per lot
1910
Median year built
7%
Properties over a historic stream or pond
Stats computed from Flood Form’s NYC parcel data as of October 9, 2026
Common solutions for Sunset Park properties
Downspout Diversion
Redirects roof runoff away from the combined sewer and into landscaped or permeable areas on the lot.
Infiltration System
Drywells or infiltration chambers that let stormwater soak into the ground on-site instead of entering the sewer.
Detention System
Holds stormwater temporarily and releases it slowly, reducing peak flow into the combined sewer during a storm.
Drain Improvement
Upgrades yard, area, or foundation drains so water is carried away from the building instead of pooling.
Foundation Waterproofing
Protects the foundation from groundwater intrusion, relevant where groundwater exposure runs high.
Nearby sewersheds
- OH-002Borough Park17,937 properties · 34% with Moderate or High stormwater exposure
- OH-019Bay Ridge1,285 properties · 44% with Moderate or High stormwater exposure
- OH-004Sunset Park4,117 properties · 21% with Moderate or High stormwater exposure
- OH-018Bay Ridge4,732 properties · 35% with Moderate or High stormwater exposure
- OH-015Bensonhurst21,675 properties · 37% with Moderate or High stormwater exposure
- OH-006Park Slope3,208 properties · 27% with Moderate or High stormwater exposure
Want to see where your specific property stands?
Get Your Property’s Flood Form