Replace the first sentence with, "Blackwater is wastewater containing urine or fecal matter that should be discharged to the sanitary drainage system of the building or premises in accordance with the International Plumbing Code."
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Credit language
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Requirements
Option 1
Reduce potable water use for building sewage conveyance by 50% through the use of water-conserving fixtures (e.g., water closets, urinals) or nonpotable water (e.g., captured rainwater, recycled graywater, on-site or municipally treated wastewater).OR
Option 2
Treat 50% of wastewater on-site to tertiary standards. Treated water must be infiltrated or used on-site. See all forum discussions about this credit »What does it cost?
Cost estimates for this credit
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Learn more about The Cost of LEED v4 »Frequently asked questions
The credit language says the Option 2 involves a reduction in wastewater. Does that mean that all water, including process water, should be included?The answer to this question is available to LEEDuser premium members. Start a free trial » (If you're already a premium member, log in here.) |
Can project teams include reclaimed water systems that are planned and funded, but not completed?The answer to this question is available to LEEDuser premium members. Start a free trial » (If you're already a premium member, log in here.) |
Addenda
10/1/2012 – Updated: 2/14/2015
Reference Guide Correction
Description of change:
Campus Applicable
No
Internationally Applicable:
No
10/1/2013
LEED Interpretation
Inquiry:
In what Water Efficiency credits may desalinated seawater be applied as a non-potable water source?
Ruling:
Update October 20, 2016: See the updated “Water Use Reduction Additional Guidance” document for new guidance on applying seawater or municipal wastewater to v2009 Water Efficiency credits.
Original ruling October 1, 2013
Desalinated seawater that is not treated to potable drinking water standards may be applied as a non-potable water source in the following credits:
- WEc1 Water Efficient Landscaping
- WEc2 Innovative Wastewater Technologies
- WEc4 Cooling Tower Water Management (in LEED-EBOM)
- WEc4.2 Water Use Reduction – Cooling Towers (in LEED-Healthcare)
- WEc4 Process Water Use Reduction (in LEED-Schools for other (non-food service) equipment types such as cooling towers)
Refer to the guidance document Applicability of Seawater in Water Efficiency credits. Desalinated seawater may NOT be applied in WEp1/c3 Water Use Reduction. The focus of the water use reduction prerequisite and credit is fixture efficiency and on-site water reuse. Because sourcing water from the sea does not constitute a form of water reuse, desalinated seawater is not applicable to WEp1 regardless of whether the seawater is treated onsite or offsite. In order to take credit for using desalinated seawater as a non-potable water source in applicable Water Efficiency credits, the desalinated seawater must be:
1) Municipally supplied or explicitly approved by the municipality for on-site treatment systems,
2) Meet all applicable code and permitting requirements so as to not contaminate the system served with high salinity,
3) Treated to an appropriate level for non-potable uses, and
4) The on-site energy use to desalinate the seawater must be included in the EAp2/EAc1 calculations.
Note that seawater is water from a sea or ocean. Salty groundwater or brackish well water in coastal areas is not considered nonpotable seawater. Groundwater and water sourced from naturally occurring surface water bodies, such as streams, rivers, and lakes is also not applicable. Only seawater sourced directly from a sea or ocean may be applied
Campus Applicable
No
Internationally Applicable:
Yes
10/2/2006
LEED Interpretation
Inquiry:
Credit Interpretation Request - Use of Reclaimed Water To minimize the amount of potable water use within the facility, Building 510 facility has been designed to utilize reclaimed water provided by West Basin MWD and the City of Torrance to serve all of the project\'s flushing waste water and irrigation needs. West Basin MWD have advised Honda that Reclaimed Water should be available to the site in time for the building being completed in May 2007. American Honda is working closely with West Basin MWD and the City of Torrance to expedite this process and ensure that the Reclaimed Water connection is made in line with this schedule. The facility is currently under construction and the plumbing scheme is approved and being installed to include the use of reclaimed water, and both West Basin MWD and the City of Torrance are fully involved in this process. Despite American Honda\'s obvious commitment to using Reclaimed Water, there are a number of City logistical issues that may delay the actual Reclaimed Water activation date beyond the proposed occupation of the building. These primarily relate to achieving the following City of Torrance approvals: 1.The civil engineering works required to make the final branch connection from the reclaimed water main to the site. This would involve civil work on what is a major street and the City is concerned about the traffic impact, which may drive the schedule for this work. 2.The City of Torrance Plumbing and Reclaimed Water Inspectors have the final say as to when the Reclaimed Water supply. To minimize the risk associated with these approvals, both of which are outside of American Honda\'s direct control, American Honda are ensuring that both West Basin MWD and the City of Torrance have been fully involved in both the design and installation of the reclaimed water system. To support this CIR, we have additional documents from American Honda, West Basin MWD and The City of Torrance, confirming their commitment to providing the reclaimed water supply to the building, which can be provided if necessary. Can you please confirm that it is acceptable to take credit for the use of Reclaimed Water within our LEED NC 2.1 submittal even though final activation may occur after the building\'s initial occupation.
Ruling:
Update October 20, 2016: See the updated “Water Use Reduction Additional Guidance” document for new guidance on applying seawater or municipal wastewater to v2009 Water Efficiency credits.
Original ruling October 2, 2006
To meet the intent of this credit provide a contract signed by both parties, indicating that this water will be provided within a one year period from the LEED submittal. Submittal documents must also indicate required infrastructure for the use of this water and state that the local jurisdiction has approved the use of the volume of water for this project.
Campus Applicable
No
Internationally Applicable:
No
11/1/2011
LEED Interpretation
Inquiry:
Can a project use municipally supplied treated seawater for toilet flushing and earn credit under innovative wastewater?
Ruling:
Treated seawater is acceptable for use for toilet flushing under the following conditions: 1) the water is municipally supplied or explicitly approved by the municipality and 2) meets all applicable codes and permitting requirements, so as not to contaminate the municipal wastewater system with high salinity. This source is considered innovative wastewater because it offsets the use of potable water from a fresh water source.
**Update October 1, 2013: Note that seawater must be treated to appropriate levels for non-potable uses; seawater that is treated to potable drinking water standards would not apply. Any on-site energy use to desalinate the seawater must be included in the EAp2/c1 calculations. Refer to the guidance document. Applicability of WE credits also modified.
Campus Applicable
No
Internationally Applicable:
Yes
2/10/2009
LEED Interpretation
Inquiry:
This CIR seeks clarification on what fixtures and systems are covered in WE Credit 2. The credit specifically mentions water closets and urinals as fixtures for conveying building sewage. The subject project is a 35,000 sf office building for dentists and orthodontists. A typical office of this kind uses a water-intensive vacuum system for conveyance of human biological waste in the form of blood, saliva and mucous. A number of the doctors are considering using "waterless" vacuum systems that drastically cut the demand for potable water for purposes of conveying human biological waste. We seek guidance on the following: Should the fixtures that comprise a dentists\' vacuum system for wastewater (blackwater) conveyance be considered when calculating WE Credit 2.
Ruling:
The applicant is requesting clarification whether fixtures that comprise a dentists\' vacuum system for wastewater conveyance should be considered in the WEc2 calculations. Water use from dentists\' vacuum systems is considered process water use and is not eligible for consideration under WEc2 and WEc3. Previous CIRs dated 2/21/2007 and 3/9/2004 contain additional clarification regarding process water use. Note: this ruling does not apply to Core and Shell projects. Applicable Internationally.
Campus Applicable
No
Internationally Applicable:
Yes
5/9/2011
LEED Interpretation
Inquiry:
Can project team include reclaimed water systems that are planned and funded, but will not be completed until 3 to 5 years after occupancy in credit calculations?
Ruling:
Update October 20, 2016: See the updated “Water Use Reduction Additional Guidance” document for new guidance on applying seawater or municipal wastewater to v2009 Water Efficiency credits.
Original ruling May 9, 2011
Per the LEED NC v2.1 WEc2 CIR ruling dated 10/2/2006, projects may only count future infrastructure such as reclaimed water systems so long as they will be completed and functional within 1 year. Applicable internationally.
Campus Applicable
No
Internationally Applicable:
Yes
4/1/2013
LEED Interpretation
Inquiry:
For campus projects, can wastewater treatment facilities located outside of the LEED project boundary but within the campus boundary qualify as on-site for the purposes of this credit?
Ruling:
"Update October 20, 2016: Campus projects may continue to utilize a wastewater treatment facility located outside of the LEED project boundary as long as it is within the campus boundary for Option 2 in WEc2: Innovative Wastewater Technologies. Treated water must be infiltrated or used on-site by the project. The only change to this ruling is that the campus treated wastewater can also apply in WEc3: Water Use Reduction, if reused in the project’s flush fixtures. See the updated “Water Use Reduction Additional Guidance” document.
Original ruling April 1, 2013:
Yes, campus projects may utilize a wastewater treatment facility located outside of the LEED project boundary as long as it is within the campus boundary for Option 2. Treated water must be infiltrated or used on-site by the project.
Please note that a campus scale wastewater treatment facility located outside of the LEED project boundary would be considered a municipally supplied non-potable water source for all other Water Efficiency credits, and would not be considered an on-site non-potable water source in WEp1 Water Use Reduction. Applicable Internationally."
Campus Applicable
Yes
Internationally Applicable:
Yes
11/1/2011
LEED Interpretation
Inquiry:
Can reverse osmosis reject water be used as an innovative wastewater source? Reverse osmosis water is often used in lab, hospital and other process water settings.
Ruling:
Yes, on-site reverse osmosis reject water is an acceptable non-potable water source. Applicable internationally.
Campus Applicable
No
Internationally Applicable:
Yes
10/22/2007
LEED Interpretation
Inquiry:
The project has a subterranean parking garage for 49 vehicles (19,247 sqft) that is within a mile of the Napa River. With this close proximity to the river and a high water table, the parking garage has ground water infiltration that is being pumped out at 1000 gallons per day. The captured ground water is being filtered (e.g. motor oil, fuels, paints/stains and solvents, asphalt products, concrete, herbicides, pesticides, and TSS, etc.) and pumped out of the garage to the city storm drain system, according to city code and San Francisco Bay Area Storm Water Management Agency Standards. The question is, could this captured ground water be used in the building as graywater for flushing toilets and urinals to offset potable water use and thereby qualify for LEED NC v2.2 Water Efficiency credits?
Ruling:
The applicant is proposing to use groundwater that has been pumped to prevent flooding to reduce potable water demand by using it for flushing toilets and urinals for WEc2. This strategy is acceptable as long as the water is only being pumped to keep the building dry; sinking a well or pumping more water than is necessary are not acceptable strategies. If the water that the project team is using is water that would be produced and discharged anyway, then the project team may use include the reused water in the calculations for the credit. The water quality of the water being used in toilets and urinals should be addressed in cases of recycled water that is untreated or minimally treated. States and regulatory agencies tend to require the water to be up to potable water standards before it goes into the toilet or sink. Note that the water quality should meet local standards and consult manufacturer recommendations for compatibility of parts with greywater use. As a point of clarification, captured groundwater is different than greywater; the term should be changed to alternate on site water sources in this CIR. Applicable Internationally.
Campus Applicable
No
Internationally Applicable:
Yes
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© Copyright U.S. Green Building Council, Inc. All rights reserved.
Requirements
Option 1
Reduce potable water use for building sewage conveyance by 50% through the use of water-conserving fixtures (e.g., water closets, urinals) or nonpotable water (e.g., captured rainwater, recycled graywater, on-site or municipally treated wastewater).OR
Option 2
Treat 50% of wastewater on-site to tertiary standards. Treated water must be infiltrated or used on-site.XX%
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The credit language says the Option 2 involves a reduction in wastewater. Does that mean that all water, including process water, should be included?The answer to this question is available to LEEDuser premium members. Start a free trial » (If you're already a premium member, log in here.) |
Can project teams include reclaimed water systems that are planned and funded, but not completed?The answer to this question is available to LEEDuser premium members. Start a free trial » (If you're already a premium member, log in here.) |
10/1/2012 – Updated: 2/14/2015
Reference Guide Correction
Description of change:
Replace the first sentence with, "Blackwater is wastewater containing urine or fecal matter that should be discharged to the sanitary drainage system of the building or premises in accordance with the International Plumbing Code."
Campus Applicable
No
Internationally Applicable:
No
10/1/2013
LEED Interpretation
Inquiry:
In what Water Efficiency credits may desalinated seawater be applied as a non-potable water source?
Ruling:
Update October 20, 2016: See the updated “Water Use Reduction Additional Guidance” document for new guidance on applying seawater or municipal wastewater to v2009 Water Efficiency credits.
Original ruling October 1, 2013
Desalinated seawater that is not treated to potable drinking water standards may be applied as a non-potable water source in the following credits:
- WEc1 Water Efficient Landscaping
- WEc2 Innovative Wastewater Technologies
- WEc4 Cooling Tower Water Management (in LEED-EBOM)
- WEc4.2 Water Use Reduction – Cooling Towers (in LEED-Healthcare)
- WEc4 Process Water Use Reduction (in LEED-Schools for other (non-food service) equipment types such as cooling towers)
Refer to the guidance document Applicability of Seawater in Water Efficiency credits. Desalinated seawater may NOT be applied in WEp1/c3 Water Use Reduction. The focus of the water use reduction prerequisite and credit is fixture efficiency and on-site water reuse. Because sourcing water from the sea does not constitute a form of water reuse, desalinated seawater is not applicable to WEp1 regardless of whether the seawater is treated onsite or offsite. In order to take credit for using desalinated seawater as a non-potable water source in applicable Water Efficiency credits, the desalinated seawater must be:
1) Municipally supplied or explicitly approved by the municipality for on-site treatment systems,
2) Meet all applicable code and permitting requirements so as to not contaminate the system served with high salinity,
3) Treated to an appropriate level for non-potable uses, and
4) The on-site energy use to desalinate the seawater must be included in the EAp2/EAc1 calculations.
Note that seawater is water from a sea or ocean. Salty groundwater or brackish well water in coastal areas is not considered nonpotable seawater. Groundwater and water sourced from naturally occurring surface water bodies, such as streams, rivers, and lakes is also not applicable. Only seawater sourced directly from a sea or ocean may be applied
Campus Applicable
No
Internationally Applicable:
Yes
10/2/2006
LEED Interpretation
Inquiry:
Credit Interpretation Request - Use of Reclaimed Water To minimize the amount of potable water use within the facility, Building 510 facility has been designed to utilize reclaimed water provided by West Basin MWD and the City of Torrance to serve all of the project\'s flushing waste water and irrigation needs. West Basin MWD have advised Honda that Reclaimed Water should be available to the site in time for the building being completed in May 2007. American Honda is working closely with West Basin MWD and the City of Torrance to expedite this process and ensure that the Reclaimed Water connection is made in line with this schedule. The facility is currently under construction and the plumbing scheme is approved and being installed to include the use of reclaimed water, and both West Basin MWD and the City of Torrance are fully involved in this process. Despite American Honda\'s obvious commitment to using Reclaimed Water, there are a number of City logistical issues that may delay the actual Reclaimed Water activation date beyond the proposed occupation of the building. These primarily relate to achieving the following City of Torrance approvals: 1.The civil engineering works required to make the final branch connection from the reclaimed water main to the site. This would involve civil work on what is a major street and the City is concerned about the traffic impact, which may drive the schedule for this work. 2.The City of Torrance Plumbing and Reclaimed Water Inspectors have the final say as to when the Reclaimed Water supply. To minimize the risk associated with these approvals, both of which are outside of American Honda\'s direct control, American Honda are ensuring that both West Basin MWD and the City of Torrance have been fully involved in both the design and installation of the reclaimed water system. To support this CIR, we have additional documents from American Honda, West Basin MWD and The City of Torrance, confirming their commitment to providing the reclaimed water supply to the building, which can be provided if necessary. Can you please confirm that it is acceptable to take credit for the use of Reclaimed Water within our LEED NC 2.1 submittal even though final activation may occur after the building\'s initial occupation.
Ruling:
Update October 20, 2016: See the updated “Water Use Reduction Additional Guidance” document for new guidance on applying seawater or municipal wastewater to v2009 Water Efficiency credits.
Original ruling October 2, 2006
To meet the intent of this credit provide a contract signed by both parties, indicating that this water will be provided within a one year period from the LEED submittal. Submittal documents must also indicate required infrastructure for the use of this water and state that the local jurisdiction has approved the use of the volume of water for this project.
Campus Applicable
No
Internationally Applicable:
No
11/1/2011
LEED Interpretation
Inquiry:
Can a project use municipally supplied treated seawater for toilet flushing and earn credit under innovative wastewater?
Ruling:
Treated seawater is acceptable for use for toilet flushing under the following conditions: 1) the water is municipally supplied or explicitly approved by the municipality and 2) meets all applicable codes and permitting requirements, so as not to contaminate the municipal wastewater system with high salinity. This source is considered innovative wastewater because it offsets the use of potable water from a fresh water source.
**Update October 1, 2013: Note that seawater must be treated to appropriate levels for non-potable uses; seawater that is treated to potable drinking water standards would not apply. Any on-site energy use to desalinate the seawater must be included in the EAp2/c1 calculations. Refer to the guidance document. Applicability of WE credits also modified.
Campus Applicable
No
Internationally Applicable:
Yes
2/10/2009
LEED Interpretation
Inquiry:
This CIR seeks clarification on what fixtures and systems are covered in WE Credit 2. The credit specifically mentions water closets and urinals as fixtures for conveying building sewage. The subject project is a 35,000 sf office building for dentists and orthodontists. A typical office of this kind uses a water-intensive vacuum system for conveyance of human biological waste in the form of blood, saliva and mucous. A number of the doctors are considering using "waterless" vacuum systems that drastically cut the demand for potable water for purposes of conveying human biological waste. We seek guidance on the following: Should the fixtures that comprise a dentists\' vacuum system for wastewater (blackwater) conveyance be considered when calculating WE Credit 2.
Ruling:
The applicant is requesting clarification whether fixtures that comprise a dentists\' vacuum system for wastewater conveyance should be considered in the WEc2 calculations. Water use from dentists\' vacuum systems is considered process water use and is not eligible for consideration under WEc2 and WEc3. Previous CIRs dated 2/21/2007 and 3/9/2004 contain additional clarification regarding process water use. Note: this ruling does not apply to Core and Shell projects. Applicable Internationally.
Campus Applicable
No
Internationally Applicable:
Yes
5/9/2011
LEED Interpretation
Inquiry:
Can project team include reclaimed water systems that are planned and funded, but will not be completed until 3 to 5 years after occupancy in credit calculations?
Ruling:
Update October 20, 2016: See the updated “Water Use Reduction Additional Guidance” document for new guidance on applying seawater or municipal wastewater to v2009 Water Efficiency credits.
Original ruling May 9, 2011
Per the LEED NC v2.1 WEc2 CIR ruling dated 10/2/2006, projects may only count future infrastructure such as reclaimed water systems so long as they will be completed and functional within 1 year. Applicable internationally.
Campus Applicable
No
Internationally Applicable:
Yes
4/1/2013
LEED Interpretation
Inquiry:
For campus projects, can wastewater treatment facilities located outside of the LEED project boundary but within the campus boundary qualify as on-site for the purposes of this credit?
Ruling:
"Update October 20, 2016: Campus projects may continue to utilize a wastewater treatment facility located outside of the LEED project boundary as long as it is within the campus boundary for Option 2 in WEc2: Innovative Wastewater Technologies. Treated water must be infiltrated or used on-site by the project. The only change to this ruling is that the campus treated wastewater can also apply in WEc3: Water Use Reduction, if reused in the project’s flush fixtures. See the updated “Water Use Reduction Additional Guidance” document.
Original ruling April 1, 2013:
Yes, campus projects may utilize a wastewater treatment facility located outside of the LEED project boundary as long as it is within the campus boundary for Option 2. Treated water must be infiltrated or used on-site by the project.
Please note that a campus scale wastewater treatment facility located outside of the LEED project boundary would be considered a municipally supplied non-potable water source for all other Water Efficiency credits, and would not be considered an on-site non-potable water source in WEp1 Water Use Reduction. Applicable Internationally."
Campus Applicable
Yes
Internationally Applicable:
Yes
11/1/2011
LEED Interpretation
Inquiry:
Can reverse osmosis reject water be used as an innovative wastewater source? Reverse osmosis water is often used in lab, hospital and other process water settings.
Ruling:
Yes, on-site reverse osmosis reject water is an acceptable non-potable water source. Applicable internationally.
Campus Applicable
No
Internationally Applicable:
Yes
10/22/2007
LEED Interpretation
Inquiry:
The project has a subterranean parking garage for 49 vehicles (19,247 sqft) that is within a mile of the Napa River. With this close proximity to the river and a high water table, the parking garage has ground water infiltration that is being pumped out at 1000 gallons per day. The captured ground water is being filtered (e.g. motor oil, fuels, paints/stains and solvents, asphalt products, concrete, herbicides, pesticides, and TSS, etc.) and pumped out of the garage to the city storm drain system, according to city code and San Francisco Bay Area Storm Water Management Agency Standards. The question is, could this captured ground water be used in the building as graywater for flushing toilets and urinals to offset potable water use and thereby qualify for LEED NC v2.2 Water Efficiency credits?
Ruling:
The applicant is proposing to use groundwater that has been pumped to prevent flooding to reduce potable water demand by using it for flushing toilets and urinals for WEc2. This strategy is acceptable as long as the water is only being pumped to keep the building dry; sinking a well or pumping more water than is necessary are not acceptable strategies. If the water that the project team is using is water that would be produced and discharged anyway, then the project team may use include the reused water in the calculations for the credit. The water quality of the water being used in toilets and urinals should be addressed in cases of recycled water that is untreated or minimally treated. States and regulatory agencies tend to require the water to be up to potable water standards before it goes into the toilet or sink. Note that the water quality should meet local standards and consult manufacturer recommendations for compatibility of parts with greywater use. As a point of clarification, captured groundwater is different than greywater; the term should be changed to alternate on site water sources in this CIR. Applicable Internationally.
Campus Applicable
No
Internationally Applicable:
Yes
LEEDuser expert
Amy Rider
KEMA Services
Sustainability Manager
