Sewershed NCB-013 · NYC DEP Combined Sewer Overflow Tributary Area
NCB-013 - South Williamsburg, Brooklyn
Properties in this area share the NCB-013 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 South Williamsburg, Brooklyn specifically.
NCB-013 is a combined sewer area covering 267 properties in South Williamsburg, Brooklyn. Flood Form rates 29% of them Moderate or High for stormwater exposure, and 10% for groundwater. 68% of lots have yard area that legally qualifies for on-site infiltration. Ground elevation is typically 48 ft. The median building dates to 1920. 7% of parcels sit over a historic stream or pond. According to NYC DEP green infrastructure records, this sewershed drains to East River / Open Waters. NYC DEP has built 3 green infrastructure assets here.
267
Properties in sewershed
68.2%
Legally eligible for on-site infiltration
29%
Stormwater exposure: Moderate or High
10%
Groundwater exposure: Moderate or High
What sets NCB-013 apart
48 ft
Median ground elevation
86%
Average impervious cover per lot
1920
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 South Williamsburg 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
- NCB-008Williamsburg938 properties · 56% with Moderate or High stormwater exposure
- NCB-012East Williamsburg1,861 properties · 49% with Moderate or High stormwater exposure
- NCB-007Williamsburg277 properties · 62% with Moderate or High stormwater exposure
- NCB-006East Williamsburg6,259 properties · 44% with Moderate or High stormwater exposure
- NCM-042Lower East Side154 properties · 47% with Moderate or High stormwater exposure
- NCB-014Bedford-Stuyvesant16,178 properties · 39% with Moderate or High stormwater exposure
Want to see where your specific property stands?
Get Your Property’s Flood Form