Sewershed RH-034 · NYC DEP Combined Sewer Overflow Tributary Area
RH-034 - Prospect Heights, Brooklyn
Properties in this area share the RH-034 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 Prospect Heights, Brooklyn specifically.
RH-034 is a combined sewer area covering 4,975 properties in Prospect Heights, Brooklyn. Flood Form rates 38% of them Moderate or High for stormwater exposure, and 33% for groundwater. 80% of lots have yard area that legally qualifies for on-site infiltration. Ground elevation is typically 43 ft. The median building dates to 1900. 34% of parcels sit over a historic stream or pond. According to NYC DEP green infrastructure records, this sewershed drains to Gowanus Canal. NYC DEP has built 53 green infrastructure assets here.
4,975
Properties in sewershed
80.4%
Legally eligible for on-site infiltration
38%
Stormwater exposure: Moderate or High
33%
Groundwater exposure: Moderate or High
What sets RH-034 apart
43 ft
Median ground elevation
75%
Average impervious cover per lot
1900
Median year built
34%
Properties over a historic stream or pond
Stats computed from Flood Form’s NYC parcel data as of October 9, 2026
Common solutions for Prospect 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
- OH-005Gowanus336 properties · 79% with Moderate or High stormwater exposure
- OH-007Park Slope3,227 properties · 22% with Moderate or High stormwater exposure
- RH-035Carroll Gardens815 properties · 23% with Moderate or High stormwater exposure
- RH-031Carroll Gardens324 properties · 35% with Moderate or High stormwater exposure
- RH-016Cobble Hill2,042 properties · 18% 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