New York City

New York City Stormwater Manual Appendix

CityNew YorkhighNoCitations verified

Fields not found in document: document_metadata.last_revised_date

Other manuals in New York: City of Albany, City of Buffalo / Buffalo Sewer Authority, City of Rochester, City of Syracuse, City of Yonkers, New York, New York State, New York State

Document Metadata

Jurisdiction level

City

“Rules of the City of New York”
Page I

State

New York

“New York State Department of Environmental Conservation”
Page II

Version / edition

Appendix to Chapter 19.1 of Title 15 of the Rules of the City of New York published as final on February 1, 2024

“published as final on February 1, 2024”
Page I

Adoption / effective date

2024-02-01

“published as final on February 1, 2024”
Page I

Last revised date

Not found in document

No evidence cited

Relationship to state manual

independent

“meeting the NYC SWM criteria does not obviate the need for a full review of and compliance with NYSDEC SWMDM requirements, as applicable.”
Page 1-3

Design Criteria

Design storm return periods (years)

5-year, 10-year

“sites must manage the peak rate of runoff for the 10YR rainfall event ... based on a rainfall event with a 5 yr. return period”
Pages 2-17, 2-18

Water quality volume method

The volume of runoff from the 90th percentile rain event (1.5 inches of rainfall in New York City), calculated using contributing area and a runoff coefficient based on percent impervious cover.

“The volume of runoff from the 90th percentile rain event, which must be managed by SMPs, is also referred to as the water quality volume (WQV) ... In New York City, the 90th percentile rain event is 1.5 inches of rainfall”
Page 2-13

Peak flow calculation method(s)

Rational Method

“of the rainfall event. It is used primarily for sewer design. For New York City areas of 10 square miles or less these assumptions are considered valid. For areas greater than 10 square miles, other modeling techniques may be more appropriate. Development Activity: Creation”
p. 8

Hydrologic/hydraulic software

HydroCAD, EPA SWMM

“Acceptable stormwater models include HydroCAD and EPA SWMM.”
Page 4-7

Approved BMP categories

Infiltration Systems, Evapotranspiration (ET) Systems, Reuse Systems, Filtration Systems, Detention Systems

“Infiltration Systems ... Evapotranspiration (ET) Systems ... Reuse Systems ... Filtration Systems ... Detention Systems”
Page CONTENTS