Sewershed RH-011 · NYC DEP Combined Sewer Overflow Tributary Area
RH-011 - Brooklyn Heights, Brooklyn
Properties in this area share the RH-011 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 Brooklyn Heights, Brooklyn specifically.
RH-011 is a combined sewer area covering 298 properties in Brooklyn Heights, Brooklyn. Flood Form rates 29% of them Moderate or High for stormwater exposure, and 29% for groundwater. 81% of lots have yard area that legally qualifies for on-site infiltration. Ground elevation is typically 77 ft. The median building dates to 1879. 27% of parcels sit over a historic stream or pond.
298
Properties in sewershed
80.9%
Legally eligible for on-site infiltration
29%
Stormwater exposure: Moderate or High
29%
Groundwater exposure: Moderate or High
What sets RH-011 apart
77 ft
Median ground elevation
75%
Average impervious cover per lot
1879
Median year built
27%
Properties over a historic stream or pond
Stats computed from Flood Form’s NYC parcel data as of October 9, 2026
Common solutions for Brooklyn Heights 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
- RH-014Brooklyn Heights753 properties · 21% with Moderate or High stormwater exposure
- RH-012Brooklyn Heights296 properties · 34% with Moderate or High stormwater exposure
- RH-018Cobble Hill242 properties · 33% with Moderate or High stormwater exposure
- RH-016Cobble Hill2,042 properties · 18% with Moderate or High stormwater exposure
- RH-019Cobble Hill352 properties · 25% with Moderate or High stormwater exposure
- NCM-078Financial District112 properties · 74% with Moderate or High stormwater exposure
Want to see where your specific property stands?
Get Your Property’s Flood Form