NC-v4 WEc1: Outdoor water use reduction

  • Exceed the prerequisite requirements

    This credit is an extension of the outdoor water use prerequisite. It uses the same methodology and awards a point for exceeding the prerequisite requirement of 30% and reaching 50% savings. A second point can be earned by demonstrating 100% savings, but this path requires teams to use alternative water sources such as non-potable, recycled, or reclaimed.

    Teams should be aware that using alternative water sources can be very feasible, but will take some extra planning to ensure that the water will be consistently suitable for use onsite (considering both water quality and availability), which may impact design. This path will also take some additional effort to document, as the availability of alternative water sources for peak watering months will need to be justified.     

    Similar to the prerequisite, a landscape design that does not require permanent irrigation is the most straightforward way to maximize points for this credit, so long as programming and operations and maintenance practices align with a non-irrigated landscape. And teams should remember that there is a two-year establishment period for new vegetation where hand watering and/or temporary irrigation can be used.

    What’s New in LEED v4

    • The U.S. EPA WaterSense Water Budget Tool is now the referenced calculation tool.

    FAQs

    The EPA WaterSense methodology and calculator allows only certain types of irrigation to be assigned to certain vegetation types. Why is this and won’t it skew results?

    The type of irrigation that can be assigned to certain vegetation types is pre-determined in the calculator, limiting user ability to make adjustments that might better reflect the design conditions. This is likely based on EPA’s assumptions about potential changes to the irrigation system and future use. GBCIThe Green Building Certification Institute (GBCI) manages Leadership in Energy and Environmental Design (LEED) building certification and professional accreditation processes. It was established in 2008 with support from the U.S. Green Building Council (USGBC). has not provided a work-around for this yet, so if you are concerned about the methodology not accurately reflecting project conditions to a degree that impacts your ability to meet the prerequisite, consider submitting a CIRCredit Interpretation Ruling. Used by design team members experiencing difficulties in the application of a LEED prerequisite or credit to a project. Typically, difficulties arise when specific issues are not directly addressed by LEED information/guide and proposing an alternative compliance path.    

    What if we just have a little green area on our rooftop? Is there a minimum amount of landscaped area to earn the prerequisite and credit?

    There is no minimum landscape areaThe landscape area is the total site area less the building footprint, paved surfaces, water bodies, and patios. to earn the prerequisite or the credit.

    One could argue that this discourages landscaping, but according to USGBC, hardscapes are addressed and, one could argue, discouraged by other credits, so this is considered a fair approach. 

  • WE Credit 1: Outdoor water use reduction

    Intent

    To reduce outdoor water consumption.

    Requirements

    Reduce outdoor water use through one of the following options. Nonvegetated surfaces, such as permeable or impermeable pavement, should be excluded from landscape areaThe landscape area is the total site area less the building footprint, paved surfaces, water bodies, and patios. calculations. Athletic fields and playgrounds (if vegetated) and food gardens may be included or excluded at the project team’s discretion.

    Option 1. No irrigation required (2 points except Healthcare, 1 point Healthcare)

    Show that the landscape does not require a permanent irrigation system beyond a maximum two-year establishment period.

    OR

    Option 2. Reduced irrigation (1-2 points except Healthcare, 1 point Healthcare)

    Reduce the project’s landscape water requirement The amount of water that the site landscape area(s) requires for the site's peak watering month.(LWRLandscape water requirement: the amount of water that the site landscape area(s) requires for the site's peak watering month.) by at least 50% from the calculated baseline for the site’s peak watering month. Reductions must first be achieved through plant species selection and irrigation system efficiency as calculated in the Environmental Protection Agency (EPA) WaterSense Water Budget Tool.

    Additional reductions beyond 30% may be achieved using any combination of efficiency, alternative water sources, and smart scheduling technologies.

    Table 1. Points for reducing irrigation water
    Percentage reduction from baseline Points (except Healthcare) Points (Healthcare)
    50% 1 1
    100% 2



    SITES-LEED Equivalency

    This LEED credit (or a component of this credit) has been established as equivalent to a SITES v2 credit or component. For more information on using the equivalency as a substitution in your LEED or SITES project, see this article and guidance document.

Design Submittal

PencilDocumentation for this credit can be part of a Design Phase submittal.

LEED v4 Outdoor Water Use Reduction Calculator

Project teams can use the USGBC LEED v4 Outdoor Water Use Reduction Calculator, recommended for projects outside of the U.S.

The WaterSense Water Budget Tool

Project teams can use The WaterSense Water Budget Tool to ensure a measure of efficiency and regional suitability for the amount of water applied to a landscape based on local climate data.

28 Comments

0
0
R2M Solution Srl R2M Solution Srl
Apr 21 2017
LEEDuser Member
221 Thumbs Up

WE_Cr1 "Outdoor Water Use Reduction": Installation of a well

Project Location: Italy

Is it possible to install a well specifically to collect groundwater for irrigation to meet the intent of the credit to reduce potable waterWater that meets or exceeds U.S. Environmental Protection Agency drinking water quality standards (or a local equivalent outside the U.S.) and is approved for human consumption by the state or local authorities having jurisdiction; it may be supplied from wells or municipal water systems. use for irrigation?

Post a Reply
0
0
Ann Runley Carroll Partner Brookwater, Inc.
Apr 05 2017
Guest

Reclaimed water use

Project Location: United States

If I am using all reclaimed/recycled water, do I still need to use the calculator. Where do I download the calculator? By using reclaimed/recycled water, do I get 2 points?

Post a Reply
0
0
SOHA YAMANI LEED Projects Coordinator Sustainable Solutions
Dec 24 2016
Guest
792 Thumbs Up

Smart irrigation controls

Hello , in step 6 it is mentioned to Count only irrigation controls whose smart-sensor technology meets the WaterSense criteria, and that it automatically reduce 15% off the baseline , my question here if the smart sensor technology doesn't meet the water sense criteria , can it still contribute to this credit or not ? my assumption is that it can contribute but it won't achieve the 15% automatically , please clarify if possible

Post a Reply
0
0
Jing Zhang
Oct 19 2016
Guest
2 Thumbs Up

Option 2. Additional reductions beyond 30%. VS. Reduce LWR 50%

Outdoor Water Use Reduction Credit

Does option 2 means, if reduction ranges from 50% to 100%, then, at least 30% need to be achieved only through plant and irrigation system efficiency. In other word, the rest (20% to 70%) can be achieved by other means ( eg. alternative water sources, smart scheduling tech.)

If so, what's the intention of step 6?

Post a Reply
0
0
R2M Solution Srl R2M Solution Srl
Feb 22 2016
LEEDuser Member
221 Thumbs Up

indoor irrigation

Project Location: Italy

Is indoor irrigation not considered in this credit? If it isn't, could I consider it in the section "Innovation", since, in the project I'm considering, collected rainwater is used?

1
3
0
Trista Little Sustainability Manager, YR&G Feb 25 2016 LEEDuser Expert 5950 Thumbs Up

Yes, indoor irrigation is not within the scope of this credit. I'm not sure about attempting an Innovation credit for using rainwater to irrigate indoor plants. My sense is that the rules around Innovation credits have been getting more strict. Submitting a CIRCredit Interpretation Ruling. Used by design team members experiencing difficulties in the application of a LEED prerequisite or credit to a project. Typically, difficulties arise when specific issues are not directly addressed by LEED information/guide before counting on this to document an IN point is probably a wise approach, but I'd be curious to hear if anyone else has tried something like this before with any success.

2
3
0
Tristan Roberts LEED AP BD+C, Executive Editor – LEEDuser, BuildingGreen, Inc. Mar 02 2016 LEEDuser Moderator

Say more about the scope of the indoors irrigation. How big the landscaped area or planters, or is it potted plants? To some extent I would look for an tangible environmental benefit here, and scope of the impact would be relevant. I agree with Trista that getting a CIRCredit Interpretation Ruling. Used by design team members experiencing difficulties in the application of a LEED prerequisite or credit to a project. Typically, difficulties arise when specific issues are not directly addressed by LEED information/guide before counting on this would be wise.

3
3
0
Tristan Roberts LEED AP BD+C, Executive Editor – LEEDuser, BuildingGreen, Inc. Mar 02 2016 LEEDuser Moderator

Say more about the scope of the indoors irrigation. How big the landscaped area or planters, or is it potted plants? To some extent I would look for an tangible environmental benefit here, and scope of the impact would be relevant. I agree with Trista that getting a CIRCredit Interpretation Ruling. Used by design team members experiencing difficulties in the application of a LEED prerequisite or credit to a project. Typically, difficulties arise when specific issues are not directly addressed by LEED information/guide before counting on this would be wise.

Post a Reply
0
0
Nate Tsang Graduate Energy Engineer Arup
Dec 10 2015
Guest
79 Thumbs Up

Establishment Period excluded in LEED Calculator?

In the LEED calculator, can we exclude all irrigation demand within the establishment period? Thus, we would just include the permanent irrigation systems.

It discusses this briefly for the "No Irrigation" option, but does not mention it for Option 2.

Thanks!

1
1
0
Steve Loppnow Sustainability Manager, YR&G Dec 17 2015 LEEDuser Expert 3319 Thumbs Up

I haven't documented this credit for a v4 project but I'm pretty confident the answer is yes, you can exclude any data related to establishment. The calculation is based on your peak watering month and landscape design, so is estimating performance during your most intensive watering month. Nothing related to establishment here. For Option 1, the credit language is saying that you can ignore a two year establishment period, so establishment is not considered in that case either.

Post a Reply
0
0
Julien Richard Artelia
Aug 11 2015
Guest
120 Thumbs Up

Green walls

Project Location: France

Hi,

Do we have to include green walls in the calculation ? I would guess that yes since it needs water, but I want to be sure.

Also, if it has to be included, which "Plant Type or Landscape Feature" is applicable when completing the Outdoor Water Use Reduction Calculator ? I don't see any choices that would match a green wall (there is Trees, Shrubs, Groundcover, Turfgrass and Pool)
Thanks !

1
1
0
Tristan Roberts LEED AP BD+C, Executive Editor – LEEDuser, BuildingGreen, Inc. Aug 12 2015 LEEDuser Moderator

Julien, I would definitely include green walls as part of the landscaped area. What will be growing on the wall? Some kind of groundcover-type plants, I would imagine? I would probably choose the closest option.

Post a Reply
0
0
deepak cherukumilli LEED AP (BD+C) Dar al Handasah
Apr 29 2015
Guest
19 Thumbs Up

Equation2: Monthly harvested rainwater volume. (v4)

Project Location: India

Reference guide v4 BD+C:Page290:

STEP 5:

I didnot understand why a 0.15 is used in this equation. Is this for any kind of losses in the rain water storage process. Cant we just use directly equation 3 to get adjusted LWRLandscape water requirement: the amount of water that the site landscape area(s) requires for the site's peak watering month. after equation 1?

Step 6:

0.15 in equation 4 is clear to account for 15% reduction by smart controls.

1
2
0
Theresa Backhus Sites Technical Specialist, LEED, USGBC Aug 31 2015 LEEDuser Member 1048 Thumbs Up

Hi Deepak,
We will be publishing an addendum to the PDF and print versions of the BD+C Reference Guide on October 1 that addresses this issue. Step 5, specifically Equation 2, should read: "Amount available = Gallons per 1 inch of rain x Average inches rain per month." The online Reference Guide already shows this correct equation.

2
2
0
Jing Zhang Oct 19 2016 Guest 2 Thumbs Up

Hello,

I still didn't get meaning of 0.15 in equation 4. Does it mean, for the additional 30% which mentioned in option 2, only maximum 15% can be supplied by either rainwater or smart irrigation control? In addition, I couldn't find the addendum for this topic in addenda database. Could you please illustrate more?

Post a Reply
0
0
Emmanuel Pauwels Owner Green Living Projects s.l.
Feb 23 2015
LEEDuser Member
4449 Thumbs Up

No Landscape Area

In the Step-by-Step Guidance of the credit it is stated: 'This credit can also be achieved by projects that have no landscape areaThe landscape area is the total site area less the building footprint, paved surfaces, water bodies, and patios.'.

In v3 you must have a minimum vegetaded area of 5% of the Project boundary in order to apply this credit. In the section 'Changes from LEED 2009' this requirement is not mentioned as being changed.

Do you think this credit is achievable if no vegetaded space is provided?

1
2
0
Bazeeth Ahamed K M Conserve Green Building and MEP Solutions WLL Apr 30 2015 Guest 110 Thumbs Up

I have the same question as well. I came across the forum in Water use reduction - Cooling Tower which states that
"Generally in LEED you have to do something in order to earn a point rather than avoid doing something to earn the point."
In this case a project without landscape can earn points?

2
2
0
Trista Little Sustainability Manager, YR&G May 01 2015 LEEDuser Expert 5950 Thumbs Up

It does seem strange that the credit can be earned for not including landscaping in the design. But this is very explicitly stated in the Step by Step section as you note and so until official guidance comes out stating otherwise I think you should be able to earn this credit with no landscaping via Option 1. It's also the case that EBOMEBOM is an acronym for Existing Buildings: Operations & Maintenance, one of the LEED 2009 rating systems. v4 projects can earn the equivalent credit by having no landscaping, so I don't think this is unintentional.

Post a Reply
0
0
Davis Kantor LEED AP BD+C
Nov 06 2014
Guest
158 Thumbs Up

Green roof eligibility

Project Location: Switzerland

Is a non-irrigated vegetated roof included in this credit calculation? It seems obvious that an accessible green roof would be. How about a non-accessible green roof?

1
1
0
Trista Little Sustainability Manager, YR&G May 01 2015 LEEDuser Expert 5950 Thumbs Up

Hi Davis, for this credit I don't think accessibility comes into play. Since the RG doesn't appear to specifically indicate that roofs can be included or excluded from the credit calculations at the team's discretion, I would assume that it should be included.

Post a Reply
0
0
Michelle DiPenti Project Coordinator HDR, Inc.
Sep 22 2014
LEEDuser Member
171 Thumbs Up

Athletic Field Definition

Project Location: United States

Our project has an outdoor area, as a part of the sports medicine department, which patients will use to do sprints, drills, and other exercises. This area is designed to simulate the field experience. It will have turfgrass, similar to a typical football field, and will be irrigated.

Can this area be considered an "athletic field" and therefore eligible to be excluded from the calculations in order to achieve Option 1 No Irrigation Required?
Thank you!

1
3
0
Trista Little Sustainability Manager, YR&G May 01 2015 LEEDuser Expert 5950 Thumbs Up

That sounds like an athletic field to me! I'd just include a narrative describing the area and how it's used in your application.

2
3
0
Stacey Olson Associate, LEED AP, ID+C, BD+C, CID, Gensler Jun 01 2016 LEEDuser Member 506 Thumbs Up

Can you show me where it states that athletic fields can be excluded from calculations? I've reviewed the reference guide, and don't see any exclusions mentioned. Thank you!

3
3
0
Carlie Bullock-Jones, LEED Fellow, WELL AP Principal, Ecoworks Studio Jun 02 2016 LEEDuser Expert 3689 Thumbs Up

Hi Stacey,

Under the 'Requirements' section of the Outdoor Water Use Reduction prerequisite and credit the Reference Guide notes "Athletic fields and playgrounds (if vegetated) and food gardens may be included or excluded at the project team’s discretion."

Post a Reply
0
0
Adam Noureddine NEUC
Jun 04 2014
Guest
36 Thumbs Up

Credit Language

Hello,
I noticed that the credit language is the same for prerequisite 1 and the credit 1 Option 1. In my opinion, this option becomes redundant and obsolete since the prerequisite is required.

1
3
0
Lorne Mlotek BASc., LEED AP BD+C, O+M, LeadingGREEN Training and Consulting Inc, Viridis EC LLC Jun 06 2014 Guest 1605 Thumbs Up

Adam,

The only difference is the percentage threshold requirements and subsequent points awarded. The language is the same because the credit has the identical intent just pushes the thresholds higher. This is the same as it was in 2009....

Not sure what your question is.

2
3
0
Adam Noureddine NEUC Jun 10 2014 Guest 36 Thumbs Up

Thanks Lorne,
I had a problem with my web browser, option 2, detailing the threshold, did not display!

3
3
0
Lorne Mlotek BASc., LEED AP BD+C, O+M, LeadingGREEN Training and Consulting Inc, Viridis EC LLC Jun 10 2014 Guest 1605 Thumbs Up

Great!

Post a Reply

Start a new comment thread

Apr 24 2017
Type the characters you see in this picture. (verify using audio)
Type the characters you see in the picture above; if you can't read them, submit the form and a new image will be generated. Not case sensitive.

Copyright 2017 – BuildingGreen, Inc.