You can earn this credit simply by eliminating turf grass, planting native and adaptive species, and not installing an irrigation system. If those measures go too far for your project, you can still achieve the credit as long as you have some flexibility with plant species selection, and irrigation system design and controls. You may need a landscape designer to identify local or adaptive plant species that require little irrigation, to design water-efficient irrigation systems, to address the potential use of non-potable waterPotable water meets or exceeds EPA's drinking water quality standards and is approved for human consumption by the state or local authorities having jurisdiction; it may be supplied from wells or municipal water systems., and to reduce irrigation needs through zoning, grouping, and grading of the landscape.
If you do install irrigation, you must perform calculations to show the savings of the project design versus a baseline. Usually done by the landscape architect or architect, these calculations determine the percent reduction of total water applied and total potable water applied. Projects with landscaping on less than 5% of their site area cannot earn points here, so consider planters or small gardens to meet that threshold.
No, non-potable groundwater used for irrigation (other than nuisance groundwater, i.e. water pumped away from a foundation) is considered a potential potable source and would not count towards earning this credit. GBCI has upheld this rule even in cases where the local groundwater has mineral or other content that requires treatment before it can be potable.
No. This approach has been rejected by LEED reviewers, who state that these are potential sources of potable water and their use does not meet the credit intent. The LEED Reference Guide makes reference to groundwater in specifically allowing use of nuisance water that needs to be pumped away from the building—but other groundwater is not mentioned as compliant.
The baseline and design cases are the same, and they are based on the total landscaped area in the design case.
There is no minimum required irrigated area to achieve the credit. Projects without vegetation on the grounds must have vegetated areas such as courtyards, planters, or vegetated roofs equal to at least 5% of the total site area to pursue the credit. Projects with no landscaping are ineligible for the credit.
Yes, all landscaping (existing and new) must be included in the documentation.
No. LEED defines the scope of the credit as landscaping outside of the building footprintBuilding footprint is the area on a project site used by the building structure, defined by the perimeter of the building plan. Parking lots, parking garages, landscapes, and other nonbuilding facilities are not included in the building footprint..
Although this may contribute to reducing irrigation demand, this does not help with achieving the credit, as landscaped area in both the baseline and design case has to be the same (see the LEED Reference Guide for acceptable methods to earn the credit, and LEED Interpretations #6039 and #731—which have not been applied officially to LEED 2009). Although decreasing vegetated space may be a sensible option for some projects, it is not allowed to contribute to this credit. It would not match the intent of this and other credits for LEED to include an incentive to reduce vegetated area.
According to a LEED Reference Guide addendum from 7/19/2010, the time period has been increased from 12 months to 18 months.
LEED does not distinguish what characteristics make an irrigation system "temporary." However, teams have had success by installing irrigation systems with plans to disable them in some way, such as removing sprinkler heads, cutting up pipe, or causing some other severe, if not unalterable, damage to the system.
Yes. According to LEED Interpretation #998, "The approach of designing rainwater storage for a 'normal' rainfall year and providing potable water as backup is acceptable."
Eliminating turf grass, planting native and adaptive species, and not installing an irrigation system is the simplest and cheapest way to achieve this credit. It will also have several additional environmental and financial benefits not necessarily recognized by LEED, such as reducing mowing costs, energy use, emissions, pesticide and fertilizer needs, and maintenance. Start by evaluating this option, taking into account the owner’s expectations, the climate, and site conditions.
Lawn as the default landscape planting doesn't make sense in dry climates, where its lushness can only be maintained at the cost of frequent watering. Xeriscaping such as shown here, using native and drought-resistant plants, is a better choice. Las Vegas Valley Water DistrictEvaluate the project’s landscaping needs and develop water savings goals. Consider opportunities to use native or adapted vegetationAdapted (or introduced) plants reliably grow well in a given habitat with minimal winter protection, pest control, fertilization, or irrigation once their root systems are established. Adapted plants are considered low maintenance and not invasive. to reduce irrigation needs. Look for all water sources on the site, such as stormwater, graywaterGraywater is untreated household waste water which has not come into contact with toilet waste. Graywater typically includes used water from bathtubs, showers, bathroom wash basins, and water from clothes-washer and laundry tubs, though definitions may vary. Some states and local authorities also allow kitchen sink wastewater to be included in graywater. Project teams should comply with the graywater definition established by the authority having jurisdiction in the project area., treated wastewater, and note opportunities for using that water for irrigation. Include water savings goals in the Owner’s Project Requirements (OPROwner's project requirements (OPR) is a written document that details the ideas, concepts, and criteria that are determined by the owner to be important to the success of the project.) for EAp1: Fundamental Commissioning.
If your landscaping is limited to planters and small gardens, calculate vegetated area as a percentage of the total site area (including building footprint). If the planter and garden area is at least 5% of the total site, you’re eligible for both credit options. If you’re just below that amount, you're ineligible for this credit. Consider adding planters as an amenity for the building and a way to earn the credit.
Using alternative water sources for irrigation may add costs compared with conventional irrigation. For example, a rainwater cistern will be an added cost, and space must be found for it. However, this may lead to cost reductions in other areas, such as reduced stormwater retention infrastructure, or lower water and sewer costs.
Research native or drought-tolerant plants and efficient irrigation systems and controls. Check for local incentives for efficient systems and controls.
Evaluate the potential for nonpotable waterNonpotable water: does not meet EPA's drinking water quality standards and is not approved for human consumption by the state or local authorities having jurisdiction. Water that is unsafe or unpalatable to drink because it contains pollutants, contaminants, minerals, or infective agents. sources, including rainwater reuse and graywaterGraywater is untreated household waste water which has not come into contact with toilet waste. Graywater typically includes used water from bathtubs, showers, bathroom wash basins, and water from clothes-washer and laundry tubs, though definitions may vary. Some states and local authorities also allow kitchen sink wastewater to be included in graywater. Project teams should comply with the graywater definition established by the authority having jurisdiction in the project area. reuse. If non-potable water use seems feasible for your project evaluate the water demand for your landscape and the quantity of water reuse available to your project. Calculations, usually done by the landscape architect, have to account for annual rainfall on a monthly basis for the project location. Rainwater, which may need basic filtration but not usually additional treatment, can be piped directly to plantings to reduce the need for potable irrigation water. Evaluate the potential for graywater. Research graywater or rainwater regulations, and local incentives. Check with local authorities on acceptable rainwater and graywater capture, collection, and reuse methods. Local codes may place limits on some uses of alternative water supplies. Develop a water budget, both project-wide and for landscape irrigation.
Work with the whole project team to evaluate synergies and tradeoffs with other LEED credits or green building strategies. These may include using rain gardens for stormwater infiltration, trees for shading the building and hardscapes for cooling-load reduction, porous surfaces, soil selection encouraging infiltration, windbreaks, water reuse, rainwater capture and acoustical barriers.
The following water sources count as reused for credit purposes: graywaterGraywater is untreated household waste water which has not come into contact with toilet waste. Graywater typically includes used water from bathtubs, showers, bathroom wash basins, and water from clothes-washer and laundry tubs, though definitions may vary. Some states and local authorities also allow kitchen sink wastewater to be included in graywater. Project teams should comply with the graywater definition established by the authority having jurisdiction in the project area. (lavatory, sink and shower water), harvested rainwater (cistern, underground, or pond), nuisance water (water that must be pumped away from the building), treated wastewater, air-conditioner condensate, reverse-osmosis reject, and sump-pump water. All well water is counted as potable for credit purposes.
Starting the LEED calculations early, along with early completion of a compliant landscape design can avoid costly redesign due to non-compliance.
For Option 2: No Potable Water Use or No Irrigation, projects have to achieve a 50% reduction in total water applied in addition to eliminating irrigating with potable water. That is, even if a project uses non-potable water for irrigation, it must also reduce the total water use for irrigation by 50%. To use non-potable water to pursue Option 2, projects must provide a detailed narrative on the actual source and available quantity of the non-potable water as well as the anticipated schedule for implementation of the non-potable system.
You can avoid submitting calculations for credit compliance by not using permanent irrigation. In this case, no permanent irrigation system can be installed, even with the intent to turn it off. Irrigation for plant establishment, allowable for one year, must be manual, or through temporary, above-grade systems. Using hose bibs to water when plants are being established and during drought conditions is allowed as “temporary irrigation.”
Look for local incentives for sub-grade irrigation, efficient irrigation, irrigation controls, and/or irrigation sub-metering. For example, one city provides up to $7,000 per acre-foot of water saved, and another program provided rebates up to $1,000 per acre for weather-based irrigation controls. Some municipalities even support “cash for grass” programs that provide rebates for the replacement of turf and with native plantings. For example, one pilot program provides $1.00 per square foot of replaced turf grass.
Evaluate a number of scenarios to achieve the credit. Look for options that work best for the design, and see if there are any trade-offs or overlaps with other LEED credits.
If irrigation is necessary, drip irrigation is a water-efficient way to deliver it where it is needed, with minimal evaporative losses. City of San Luis Obisbo Utilities DepartmentDesign landscape and irrigation systems to maximize native and adapted species, use efficient irrigation technology, and reuse water where possible. Evaluate the different irrigation technologies for their efficiency and suitability to the project. These include subsurface, bubbler, drip, and rotor sprinkler. Installing weather controls or soil moisture sensors can greatly reduce unnecessary irrigation. Consider directing rainwater to planting beds to reduce the need for potable irrigation water.
Detailed calculations to demonstrate irrigation efficiency will be required from the landscape architect. The study “Performance and Water Conservation Potential of Multi-Stream, Multi-Trajectory Rotating Sprinklers for Landscape Irrigation” (see Resources) provides expected water conservation percentages derived from measured data. Efficiency ratings provided by manufacturers for irrigation components and controls can be used for calculations, but most manufacturers do not provide this data, so you’ll need additional calculations.
Use of drip irrigation helps to conserve water. BuildingGreen ImageThe design cost of a drip irrigation system is generally comparable to a standard system. However, installation might be more expensive for drip irrigation, particularly as plant density increases.
The landscape architect calculates the potential for rainwater reuse and corresponding cistern sizes to accommodate landscape and other rainwater reuse applications. Calculations must account for annual rainfall of the project location.
There are fewer codes and associated costs for collecting and using rainwater for irrigation than for interior water reuse. Harvested rainwater can often be reused for irrigation purposes with minimal treatment, although filtration is usually needed.
The mechanical engineer calculates the potential for graywaterGraywater is untreated household waste water which has not come into contact with toilet waste. Graywater typically includes used water from bathtubs, showers, bathroom wash basins, and water from clothes-washer and laundry tubs, though definitions may vary. Some states and local authorities also allow kitchen sink wastewater to be included in graywater. Project teams should comply with the graywater definition established by the authority having jurisdiction in the project area. reuse and applicable treatment methods.
Perform LEED calculations to evaluate compliance. Only “softscape” areas are included in calculations. Projects that replace landscape irrigation with hardscape to reduce irrigation needs cannot count this area in their calculations.Use the calculator provided in the LEED Online credit form to evaluate compliance.
The landscape architect develops a baseline outdoor-water-use calculation based on mid-summer (July) and compares that to a calculation for the planned project design case water use (also for July). The difference is the percent reduction and identifies credit achievement. Factors included in the calculations are: plant species, density, microclimate, evapotranspiration rate, irrigation efficiency,, and non-potable waterPotable water meets or exceeds EPA's drinking water quality standards 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, and controller efficiency (gains from controller efficiency cannot exceed 30% in July). The local project baseline case is a subjective calculation that will vary by city and is based on standard practice in that region. The landscape design case is created by setting the irrigation variables to values representative of the actual designed landscape plan. The landscape water efficiency boundary used must be the same project boundary used for all other LEED credits. (See the documentation toolkit for more information.)
LEED for Schools projects can decide to exclude playing fields from the landscape calculation. However, the playing fields must then be excluded from all LEED calculations, including open space requirements. If such areas are included, they must be included in all other applicable Water Efficiency credit calculations (unless otherwise noted).
The landscape architect runs final outdoor water use calculations for the project’s design case annual water usage. These calculations should confirm that the landscape water reduction goals are met. If the goals are not met, adjust the landscape and irrigation design as needed.
The landscape architect provides LEED documentation for submittal to LEED Online.
The commissioning agent commissions irrigation and water reuse systems to ensure they operate as designed.
Create a maintenance plan to ensure ongoing, as-designed performance of irrigation systems and equipment. Doing so will also contribute to LEED-EBOMEBOM is an acronym for Existing Buildings: Operations & Maintenance, one of the LEED 2009 rating sytems. credit compliance. Along with the maintenance plan, provide product manuals for irrigation systems including weather and moisture controls to maintenance personnel, and discuss irrigation and planting maintenance needs. When operational, verify that the sprinkler system is not spraying the building, to avoid water waste, mold and termite damage. Also avoid wasting water spraying on other hardscapeHardscape consists of the inanimate elements of the building landscaping. Examples include pavement, roadways, stone walls, concrete paths and sidewalks, and concrete, brick, and tile patios. surfaces like roads and sidewalks.
Minimize irrigation frequency in an effort to conserve water. Apply irrigation at the lowest rate required to keep plants healthy. New plants may need to be irrigated more, in order to establish them. Change irrigation schedules on a regular basis to adjust for seasonal variations in watering needs, including turning them off in the fall. Use an irrigation system that is tied directly to weather forecasts, or manually program irrigation clocks weekly or more often, based on projected rainfall and weather patterns.
Incorporating mulch and using mulching mowers will help keep moisture in the soil, and reduce irrigation needs. Adding compost to the soil will help maintain plant health over time and aid in moisture retention.
Creating an Integrated Pest ManagementIntegrated pest management (IPM) is the coordinated use of knowledge about pests, the environment, and pest prevention and control methods to minimize pest infestation and damage by the most economical means while minimizing hazards to people, property, and the environment. plan will offer environmental and health benefits, while contributing to the ongoing attractiveness of the landscape. Doing so will also contribute to LEED-EBOMEBOM is an acronym for Existing Buildings: Operations & Maintenance, one of the LEED 2009 rating sytems. credit compliance.
Installing a sub-metering system for irrigation water can help operators monitor water usage and detect problems early on. Doing so will also contribute LEED-EBOMEBOM is an acronym for Existing Buildings: Operations & Maintenance, one of the LEED 2009 rating sytems. credit compliance.
The cost of maintenance will vary depending on the strategy employed. For example, subsurface or drip irrigationDrip irrigation delivers water at low pressure through buried mains and submains. From the submains, water is distributed to the soil through a network of perforated tubes or emitters. Drip irrigation is a high-efficiency type of microirrigation. systems can be more difficult to maintain, because malfunctions are more hidden.
Excerpted from LEED 2009 for Schools New Construction and Major Renovations
To limit or eliminate the use of potable waterPotable water meets or exceeds EPA's drinking water quality standards and is approved for human consumption by the state or local authorities having jurisdiction; it may be supplied from wells or municipal water systems. or other natural surface or subsurface water resources available on or near the project site for landscape irrigation.
Reduce potable waterPotable water meets or exceeds EPA's drinking water quality standards and is approved for human consumption by the state or local authorities having jurisdiction; it may be supplied from wells or municipal water systems. consumption for irrigation by 50% from a calculated midsummer baseline case or using the month with the highest irrigation demand.
Reductions must be attributed to any combination of the following items:
Groundwater seepage that is pumped away from the immediate vicinity of building slabs and foundations may be used for landscape irrigation to meet the intent of this credit. However, the project team must demonstrate that doing so does not affect site stormwater management systems.
Meet the requirements for Option 1.
Use only captured rainwater, recycled wastewater, recycled graywaterGraywater is untreated household waste water which has not come into contact with toilet waste. Graywater typically includes used water from bathtubs, showers, bathroom wash basins, and water from clothes-washer and laundry tubs, though definitions may vary. Some states and local authorities also allow kitchen sink wastewater to be included in graywater. Project teams should comply with the graywater definition established by the authority having jurisdiction in the project area. or water treated and conveyed by a public agency specifically for nonpotable uses for irrigation.
Install landscaping that does not require permanent irrigation systems. Temporary irrigation systems used for plant establishment are allowed only if removed within a period not to exceed 18 months of installation.
Perform a soil/climate analysis to determine appropriate plant material and design the landscape with native or adapted plants to reduce or eliminate irrigation requirements. Where irrigation is required, use high-efficiency equipment and/or climate-based controllers.
Additionally the credit can be met when landscape irrigation is provided by raw water (excluding naturally occurring surface bodies of water, streams, or rivers, and ground water) that would otherwise be treated specifically for nonpotable uses. Only ponds designed solely for the purposes of stormwater retention or detention can be used for this credit.
ARCSA was founded to promote rainwater catchment systems in the United States. The ARCSA website provides regional resources, publications, suppliers, and membership information.
CIT is an independent research and testing facility that provides information to designers, manufacturers, and users of irrigation equipment.
This nonprofit organization focuses on promoting products that efficiently use water in irrigation applications.
The clearinghouse includes articles, reference materials, and papers on all forms of water efficiency.
The NCDC site is useful for researching local climate information such as data for rainwater harvesting calculations, and it also includes links to state climate offices.
Enter your project latitude and longitude—easily taken from Google Earth—and you will get the ETo for pretty much anywhere on earth. A note of caution: spot checking reveals that data may not be reliable in all locations. Make sure that data such as precipitation and temperatures checks out before using the ETo values proposed by the model.
This free software provides sufficient local evapotranspiration data for the United States and Canada. Access data from the closest or most climate-appropriate location.
This website provides data from the state of Texas regarding water resources and services such as groundwater mapping and water availability modeling. The site also provides brochures on indoor and outdoor water efficiency strategies.
This study provides expected water conservation percentages derived from measured data, which can be used to support water efficiency calculations for this credit.
This manual provides information about reducing water consumption through creative landscaping techniques.
Use a narrative like one of these to demonstrate no potable waterPotable water meets or exceeds EPA's drinking water quality standards 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, or no irrigation.
Use a site plan and narrative to approach and document credit compliance, like these examples from the Denver School of Science and Technology Landscape Design.
Use a narrative like this to demonstrate a 50% reduction in potable waterPotable water meets or exceeds EPA's drinking water quality standards 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.
The following links take you to the public, informational versions of the dynamic LEED Online forms for each Schools-2009 WE credit. You'll need to fill out the live versions of these forms on LEED Online for each credit you hope to earn.
Version 4 forms (newest):
Version 3 forms:
These links are posted by LEEDuser with USGBC's permission. USGBC has certain usage restrictions on these forms; for more information, visit LEED Online and click "Sample Forms Download."
Documentation for this credit can be part of a Design Phase submittal.
Our project has planned a large area to be planted with native material needing no irrigation. (the plants are installed with gel pods that hold enough water for the plant material to root) For the design case, we are documenting the irrigation system as other, utilizing 0 water. How do we document the baseline case? Would we document the irrigation system as drip as that is the common practice in our area.
Projects other than Schools: Can they exclude playing fields in certain credits just like Schools can? (eg the training playing grounds of a soccer team, in a site that"ll accommodate the team"s guest house/dormitories building)
I am working on a school project in Colorado. We have a large amount of native seed that the school does not want to irrigate, however we need to irrigate for establishment. I have three questions.
1, Does the irrigation have be to removed within 1 year or 18 months? I have seen both. I have seen 1 year in the book and 18 months for the regional credit.
2. My second question is do we have to use temporary irrigation? The school may want to use a water truck or "hope for rain". Not our recommendation but they are asking the question. Would the USGBC want to ensure that the native is established in order to achieve points?
3. My third question is related to above ground or in ground. Can the temporary irrigation be underground? What if we remove the heads at 1 year? Cost for underground vs, above ground is not that great and at a school you don't want the students/public damaging the irrigation lines.
1) Per the FAQ above, the time period was increased to 18 months from 12.
2) Temporary irrigation could consist of what I'll broadly call "manual" irrigation which could include sprinklers or spraying as needed. That is fine according to LEED.
3) Yes, fine to do below ground and then remove the heads. This is also covered in more detail in the FAQs above.
Our project in south-central South Dakota consists of a building addition over a previously graded turf area. We are adding no irrigation and reseeding the disturbed areas with a drought tolerant tall fescue blend. We are not adding any trees, shrubs, or other landscaping.
In the Preliminary Design and Construction Review, the credit was denied. The Review Report stated, "Reseeding disturbed areas back to their original condition does not qualify as new work. If the building has no landscaping, this credit does not apply."
There was a significant amount of site work to install underground utilites, parking lots, etc. Doesn't turf grass count as landscaping?
Mike, can you share a bit more information? Was there anything advice or other pertinent information mentioned in the review comment?
What was the baseline case for the credit calculations?
Tristan, there was no technical advice included with the review. We stated on the credit Form that there are no "trees, shrubs, or groundcover in the way of landscaping provided as part of this project", and that we are reseeding disturbed areas. I am wondering if there is confusion over our statement that there is no landscaping. We did have to seed the area around the building addition. There was grading work, site utiltiy work, and paved surfaces as a part of the site work. We included a colored site showing the extents of the seeding work. Thanks!
Did you provide a baseline case?
It sounds like something about the submission, perhaps the wording you mentioned, made it appear to the reviewer that you do not have landscaping.
p184 of BD&C Reference Guide (from LI 10217) states, "For school projects, including playgrounds and athletic fields in this credit is optional. However, if such areas are included, they must be included in all other applicable credit calculations." I'm having a tough time interpreted the "however" statement. Does anyone know if you exclude the area of the athletic field from WEc1 do you also have to exclude it from your open space calcs for SSc5.2 or other SS credits? Thanks
Addenda 7.19.10 corrected the statement to read “For school projects, including playgrounds and athletic fields in this credit is optional. However, if such areas are included, they must be included in all other Water Efficiency credit calculations (unless otherwise noted).”
When LEED ask for the reference evapotranspiration rate (ETo) for the month of July in the WEc1 form, does it mean I should provide the daily ETo for the month of July (ETo rate per day), or should I provide the monthly ETo rate on July, i.e. (daily ETo) X 31(days in July)?
It's the Et0 for the month, which you will need to fill in there. Her are the national and international resources for it:
Water Efficient Landscaping- 50% reduction
Landscape water for the project in middle east, where water is scarce is to be supplied by (municipality) Seawater Desalination plant far away from the site, will it satisfy the Credit requirements to gain points?
I assume the desalination is to provide water that is suitable for human consumption/irrigation? Option 1-50% Reduction is often achieved using potable waterPotable water meets or exceeds EPA's drinking water quality standards and is approved for human consumption by the state or local authorities having jurisdiction; it may be supplied from wells or municipal water systems. for irrigation and selecting plant species that require little water using efficient irrigation systems.
Ameet, if the desalinated water is up to potable standards (which I assume it would be), then it would not meet the credit requirements for Option 2.
I also don't think it's in the spirit of LEED to attempt this—the resource intensity of desalination doesn't make sense when applied to irrigation, regardless of "potable" or "nonpotable" labels.
I am having difficulty interpreting the paragraph in this credit describing how to deal with athletic fields. It seems to me that it would be acceptable to draw the LEED boundary including irrigated athletic fields (since they serve the school's daily function and are disturbed as a result of construction work) but exclude that irrigation from documentation for this credit. Has anyone taken that approach and had a successful review? Did you also pursue SSc5.2 Maximize Open Space?
Sylvia, as stated in the LEED Reference Guide (page 184), including athletic fields for this credit is optional. But if excluded, they must also be excluded for other credits—which I assume means SSc5.2.
We have a project using artificial turf for the football field so it does not require irrigation, but it does need to be rinsed and cooled down. I don't know the specifics of rinsing the turf but does anyone know if the water for rinsing and cooling needs to be included in this credit? Thanks.
Lauren, I would say that's not irrigation—sounds like more of a "process load." Probably not covered in LEED at all, but if it does turn up, it would be under WEc4.
if the client intends to digitally "cut-off" irrigation for native seeding after 1 year to establish - while keeping the rest of the irrigation system in tact - is this enough? Initial comments from GBCI reviewer indicates that the temporary system will need to be removed. This seems wasteful and unnecessary - however, I do understand the reluctance to believe that the system will indeed be digitally "cut-off" with a valve. What are your thoughts?
Lisa, when you say "digitally" cut off, are you referring to turning the system off by some programming function, or by turning off an actual valve? I think GBCI would have a valid concern that it can just as easily be turned back on in the future. Some more concrete way of cutting off the system may be warranted, such as removing the sprinkler heads.
Tristan - we agree and have decided to remove the irrigation heads and cap them. Hoping for approval from GBCI.
Our landscape designer has assured us that the native plant design will not require irrigation once established. The owner would prefer to install an irrigation system to use during the plant establishment, and then turn off after one year. Our project has a rainwater harvesting system that would support the irrigation needs. We already qualify for all 4 points: landscape design reduces the baseline "Total Water Applied" by 75%, and the remaining 25% is supplied from the cistern. The advantage we see is that if we can prove that less harvested rainwater will be dedicated to irrigation during the life of the building, more is available to flush toilets, and reduces the potable waterPotable water meets or exceeds EPA's drinking water quality standards 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.
Will the GBCI allow the installation of a permanent irrigation system that will be turned off after the first year of plant establishment? Or can we justify that the TWA would be reduce by x% after the first year, allowing us to dedicate a greater volume of harvested rainwater to flushing?
Tim, I think your question boils down to: when installing non-permanent irrigation, should it be factored into the water-use modeling for credit compliance?
Although I have never encountered this question before, I think the answer should probably be "no." The design is supposed to be about typical building use, not an anomalous first-year situation.
Anyone else have feedback?
No new landscaping, turf, or irrigation are planned for this project - can this credit be pursued in this case?
Rachel, you do need landscaping to be eligible for the credit. When you say no "new," do you mean there was some to begin with? It has to be at least 5% of the site area—something we discuss above under the Checklists tab.
Part of the idea here is to not incentivize projects to earn the credit by paving over everything or installing artificial turf, ec.
thank you for your response - yes, it is an existing site/building that we are doing a gut renovation and addition for. so there are existing trees and grass, which are to remain (some of the grass will be replaced). the existing trees are at least 5% of the site area. If we maintain/restore existing, are we compliant?
If that landscaping is wihin your LEED boundary, and if you don't use permanent irrigation systems on it (or if the irrigation systems meet the credit thresholds), then yes, you'd be compliant.
However, you mention turf grass. Turf grass is considered landscaping that requires permanent irrigation in most climates—which would not earn you the credit. So you may need to dig a little deeper—I recommend reviewing our guidance above under the Checklists and Doc Toolkit tabs.
Global Sustainability Manager
Installing appropriate landscape materials and capturing rainwater can contribute to infiltration and reduction of stormwater quantity.
Installing appropriate landscape materials and capturing rainwater can contribute to infiltration and improvement of stormwater quality.
Graywater reuse can help with WEp1, and goes hand-in-hand with reduction of potable water use for
Native plants used for WEc1 can promote the restoration and protection of habitat.
Consider treating wastewater onsite to use for nonpotable irrigation.
Do you know which LEED credits have the most LEED Interpretations and addenda, and which have none? The Missing Manual does. Check here first to see where you need to update yourself, and share the link with your team.
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