S T A T E O F N E W Y O R K
________________________________________________________________________
7104
2023-2024 Regular Sessions
I N S E N A T E
May 18, 2023
___________
Introduced by Sen. MATTERA -- read twice and ordered printed, and when
printed to be committed to the Committee on Environmental Conservation
AN ACT to amend the environmental conservation law, in relation to rain-
water harvesting
THE PEOPLE OF THE STATE OF NEW YORK, REPRESENTED IN SENATE AND ASSEM-
BLY, DO ENACT AS FOLLOWS:
Section 1. Article 15 of the environmental conservation law is amended
by adding a new title 35 to read as follows:
TITLE 35
RAINWATER HARVESTING
SECTION 15-3501. PURPOSE.
15-3503. RAINWATER HARVESTING FEASIBILITY.
15-3505. RAINWATER HARVESTING CONVEYANCE.
15-3507. RAINWATER HARVESTING PRETREATMENT.
15-3509. RAINWATER HARVESTING TREATMENT.
15-3511. RAINWATER HARVESTING LANDSCAPING AND VEGETATION.
15-3513. RULES AND REGULATIONS.
§ 15-3501. PURPOSE.
RAINWATER HARVESTING PRACTICES, WHEN DESIGNED TO TEMPORARILY STORE
STORMWATER RUNOFF FOR DETENTION OR RE-USE THROUGH RETENTION, MAY ASSIST
IN MEETING STORMWATER RUNOFF REDUCTION GOALS.
RAINWATER HARVESTING IS THE CAPTURE, CONVEYANCE, AND STORAGE OF
PRECIPITATION FROM IMPERVIOUS SURFACES, TYPICALLY ROOFTOPS, PRIMARILY
FOR RE-USE, RATHER THAN INFILTRATION OR RELEASE INTO A WATERWAY. RAINWA-
TER HARVESTING HAS MINIMAL SITE REQUIREMENTS COMPARED TO OTHER STORMWA-
TER MANAGEMENT PRACTICES AND MAY BE USED IN RESIDENTIAL AND INDUSTRIAL
SETTINGS FOR ANY VOLUME OF ROOFTOP RUNOFF, IF SIZED APPROPRIATELY.
RAINWATER HARVESTING MAY BE USED ON SITES WHERE DENSE DEVELOPMENT,
POLLUTANT HOTSPOTS, OR SOIL CONDITIONS PRECLUDE THE USE OF INFILTRATION
OR OTHER STORMWATER MANAGEMENT PRACTICES. THE USE OF RAINWATER HARVEST-
ING REDUCES THE AMOUNT OF STORMWATER RUNOFF ENTERING THE DRAINAGE SYSTEM
EXPLANATION--Matter in ITALICS (underscored) is new; matter in brackets
[ ] is old law to be omitted.
LBD11425-01-3
S. 7104 2
AND LOCAL RECEIVING WATERS AS WELL AS REDUCING OR DELAYING PEAK FLOW
RATES. IT IS IMPORTANT TO HAVE WELL-DEFINED OPERATION AND MAINTENANCE
PROCEDURES FOR ANY RAINWATER HARVESTING SYSTEM, IN ORDER TO PROVIDE
ADEQUATE STORAGE CAPACITY FOR SUBSEQUENT STORM EVENTS.
STORAGE TANKS FOR HARVESTED RAINWATER MAY BE SITED ABOVE- OR BELOW-
GROUND, INDOORS OR OUTDOORS, OR ON ROOFTOPS OF BUILDINGS THAT HAVE BEEN
DESIGNED TO BEAR THE LOAD OF RAINWATER STORAGE. THE MAIN COMPONENTS OF A
RAINWATER HARVESTING SYSTEM INCLUDE: A CONTRIBUTING ROOFTOP SURFACE; A
CONVEYANCE SYSTEM OF GUTTERS, DOWNSPOUTS, AND PIPES; SCREENING OR PRE-
TREATMENT FILTER AND CLEAN-OUT; A WATERTIGHT STORAGE CONTAINER; AN OVER-
FLOW PIPE; AN ACCESS HATCH; AND AN EXTRACTION SYSTEM, SUCH AS A SPOUT OR
PUMP. ADDITIONAL COMPONENTS MAY INCLUDE A FIRST FLUSH DIVERTER, PRES-
SURE TANK, AND BACKFLOW PREVENTION DEVICE.
RAIN BARRELS ARE COMMONLY USED TO STORE HARVESTED RAINWATER IN SMALL-
SCALE RESIDENTIAL SETTINGS, WHILE ABOVE- OR BELOW-GROUND CISTERNS ARE
MORE COMMONLY USED IN LARGER-SCALE INDUSTRIAL SETTINGS. RAIN BARRELS ARE
ABOVE GROUND STORAGE TANKS GENERALLY HOLDING FIFTY TO EIGHTY GALLONS,
BUT MAY HOLD UP TO TWO HUNDRED GALLONS. CISTERNS ARE SEALED TANKS, WHICH
MAY BE ABOVE OR BELOW GROUND AND GENERALLY HOLD TWO HUNDRED TO TEN THOU-
SAND GALLONS. WHILE CAREFULLY MANAGED RAIN BARRELS CAN BE A VIABLE MEANS
OF STORMWATER RUNOFF VOLUME REDUCTION FOR VERY SMALL VOLUMES OF RAINWA-
TER, THIS STANDARD IS INTENDED TO BE APPLIED TO THE LARGER STORAGE
VOLUMES AND MORE ROBUST MANAGEMENT STRATEGIES THAT ARE POSSIBLE ONLY
WITH CISTERNS.
HARVESTED RAINWATER IS OFTEN WELL-SUITED FOR REUSE IN LANDSCAPE IRRI-
GATION AND OTHER NON-POTABLE USES, INCLUDING IN TOILETS AND URINALS, AS
WELL AS HVAC MAKE-UP WATER, TOPPING OFF SWIMMING POOLS, AND WASHING
CARS. IN THE STATE, REUSE OF HARVESTED RAINWATER FOR PURPOSES OTHER THAN
IRRIGATION IS LARGELY UNADDRESSED BY CURRENT STATE REGULATIONS OR LOCAL
CODES. BECAUSE OF THIS LACK OF SPECIFIC RAINWATER HARVESTING GUIDANCE,
SOME JURISDICTIONS HAVE REGULATED HARVESTED RAINWATER AS RECLAIMED
WATER, RESULTING IN STRINGENT REQUIREMENTS THAT MAKE REUSING HARVESTED
RAINWATER CHALLENGING. THE PRACTICALITY OF RAINWATER REUSE WILL NEED TO
BE EVALUATED ON A CASE-BY-CASE BASIS.
§ 15-3503. RAINWATER HARVESTING FEASIBILITY.
THE FOLLOWING DESIGN ELEMENTS ARE REQUIRED WHEN IMPLEMENTING RAINWATER
HARVESTING PRACTICES TO CAPTURE AND RE-USE STORMWATER RUNOFF:
1. RAINWATER HARVESTING SHALL BE LIMITED TO ROOFTOP RUNOFF.
2. RAINWATER STORAGE SHALL BE DESIGNED TO CAPTURE AT LEAST 0.2 INCHES
OF RAINFALL FROM THE CONTRIBUTING ROOFTOP.
3. AN APPLICATION AREA OR WATER REUSE SHALL BE IDENTIFIED THAT IS
SUFFICIENT TO REUSE THE STORMWATER VOLUME STORED WITHIN A WEEK AT AN
APPLICATION RATE OF ONE INCH PER WEEK OVER THE IRRIGATION PERIOD FROM
MAY THROUGH SEPTEMBER.
4. FOR UNDERGROUND STORAGE TANKS, THE BOTTOM OF THE TANK SHALL BE
ABOVE GROUNDWATER LEVEL, AND THE TOP OF THE TANK SHALL BE BELOW THE
FROST LINE. STORAGE TANKS THAT ARE ABOVE GROUND OR NOT ABLE TO BE
BURIED BELOW THE FROST LINE SHALL BE APPROPRIATELY INSULATED OR DISCON-
NECTED DURING THE WINTER MONTHS TO PROTECT THE SYSTEM FROM FREEZING.
§ 15-3505. RAINWATER HARVESTING CONVEYANCE.
1. GUTTERS SHALL BE HUNG AT A MINIMUM OF ONE-HALF PERCENT FOR TWO-
THIRDS OF THE LENGTH AND AT ONE PERCENT FOR THE REMAINING ONE-THIRD OF
THE LENGTH, AND SHALL BE SET AND SIZED TO PROPERLY CAPTURE, CONTAIN, AND
CONVEY THE ONE INCH STORM EVENT AT A RATE OF ONE INCH PER HOUR.
S. 7104 3
2. OVERFLOW RUNOFF SHALL BE SAFELY CONVEYED TO A SUITABLE, DOWN-GRA-
DIENT LOCATION SUCH AS A BUFFER AREA, OPEN YARD, GRASS SWALE, OR SECOND-
ARY TREATMENT PRACTICE, AS APPLICABLE.
3. OVERFLOW CONVEYANCE AND TANK SITING SHALL BE DESIGNED TO PREVENT
PONDING OR SOIL SATURATION WITHIN TEN FEET OF BUILDING FOUNDATIONS, AND
UNDERGROUND CISTERNS SHALL BE SITED AT LEAST TEN FEET FROM BUILDING
FOUNDATIONS.
4. SYSTEMS SHALL BE DESIGNED AROUND A WATER BUDGET ANALYSIS THAT IDEN-
TIFIES HOW WATER WILL BE USED TO ENSURE THAT STORAGE CAPACITY IN THE
SYSTEM WILL BE AVAILABLE FOR SUBSEQUENT RUNOFF EVENTS.
§ 15-3507. RAINWATER HARVESTING PRETREATMENT.
1. PRETREATMENT OF RAINWATER SHALL BE PROVIDED IN THE FORM OF A FILTER
OR SCREEN TO PREVENT LEAF LITTER, SEDIMENT, AND OTHER DEBRIS FROM ENTER-
ING THE STORAGE TANK. FIRST FLUSH DIVERTERS, VORTEX FILTERS, ROOF WASH-
ERS, AND LEAF SCREENS ARE ACCEPTABLE FORMS OF PRETREATMENT. THE
PRETREATMENT SHALL BE INSTALLED EITHER IN THE GUTTER OR DOWNSPOUT OR AT
THE INLET TO THE STORAGE TANK, WITH PROPER DESIGN FOR CLEAN-OUT.
DEPENDING ON THE DESIRED USE FOR THE RAINWATER, ADDITIONAL FILTRATION
MAY BE NEEDED OR DESIRED.
2. MOSQUITO SCREENING WITH A ONE MILLIMETER MESH SIZE SHALL BE
INSTALLED AT OPENINGS TO PREVENT MOSQUITOS FROM ENTERING THE STORAGE
TANK.
§ 15-3509. RAINWATER HARVESTING TREATMENT.
1. A WATER BUDGET ANALYSIS SHALL BE PROVIDED TO THE DEPARTMENT THAT
IDENTIFIES HOW WATER WILL BE USED, TO ENSURE THAT THE SYSTEM WILL BE
AVAILABLE FOR SUBSEQUENT RUNOFF EVENTS.
2. STORAGE TANKS SHALL BE WATERTIGHT AND SHALL BE COMPOSED OF AND
SEALED WITH WATER SAFE, NON-TOXIC SUBSTANCES.
3. RAINWATER SHALL NOT BE HARVESTED FROM THE FOLLOWING ROOF TYPES: TAR
AND GRAVEL, ASBESTOS SHINGLE, AND TREATED CEDAR SHAKES. IN ADDITION,
RAINWATER SHALL NOT BE COLLECTED FROM ROOFS WITH METAL FLASHING THAT
CONTAINS LEAD.
§ 15-3511. RAINWATER HARVESTING LANDSCAPING AND VEGETATION.
STORMWATER SHALL NOT BE DIVERTED TO A RAINWATER HARVESTING SYSTEM
UNTIL THE OVERFLOW CONVEYANCE AND APPLICATION AREAS HAVE BEEN STABILIZED
WITH VEGETATION.
§ 15-3513. RULES AND REGULATIONS.
THE COMMISSIONER SHALL PROMULGATE ALL RULES AND REGULATIONS NECESSARY
FOR THE IMPLEMENTATION OF THIS TITLE.
§ 2. This act shall take effect on the ninetieth day after it shall
have become a law. Effective immediately, the addition, amendment and/or
repeal of any rule or regulation necessary for the implementation of
this act on its effective date are authorized to be made and completed
on or before such effective date.