WE: Outdoor Water Use Reduction (Prerequisite + Credit)
Use less water first. Then use smarter water.
๐ฏ Why This Topic Matters
Outdoor water use is one of the largest sources of potable water consumption in buildings.
๐ LEED focuses on:
Reducing irrigation demand first โ then using smarter water sources
๐งฉ Prerequisite vs Credit (Key Distinction)
๐ Quick Comparison Table (HIGH VALUE FOR USERS)
| Requirement | Prerequisite | Credit |
| Mandatory? | โ Yes | โ No |
| Points | 0 | Up to 2 points |
| Intent | Reduce outdoor water use | Further reduce outdoor water use |
| Option 1 | No irrigation | Same |
| Option 2 Reduction | โฅ30% | โฅ50% (1 pt), 100% (2 pts) |
| Use of alternative water | โ Not allowed for first 30% | โ Allowed beyond 30% |
๐ฏ Key Insight
Prerequisite = baseline efficiency
Credit = deeper performance
๐ฟ WE Prerequisite: Outdoor Water Use Reduction
Intent
๐ Reduce outdoor potable water consumption
Compliance Options
โ Option 1: No Irrigation Required
- No permanent irrigation system
- Allowed only for:
- โค2-year establishment period
๐ Requires:
- narrative explaining:
- rainfall adequacy
- plant suitability
โ Option 2: Reduced Irrigation
๐ Must achieve:
๐ โฅ30% reduction
(from baseline landscape water requirement)
โ๏ธ How is this calculated?
Using:
๐ EPA WaterSense Water Budget Tool
๐งฎ WaterSense Tool โ Key Steps
๐น Step 1: Climate Data
- input project location (ZIP code)
- tool generates:
- precipitation
- evapotranspiration
๐น Step 2: Landscape Inputs
- enter:
- plant types
- landscape areas
โ ๏ธ Important Rule:
๐ Include:
- vegetated areas
๐ Exclude:
- hardscape
- non-irrigated surfaces
- mulched pathways
๐น Step 3: Results
- baseline water use
- design water use
- % reduction
๐ฑ WE Credit: Outdoor Water Use Reduction
Intent
๐ Same as prerequisiteโbut with higher performance
Compliance Options
โ Option 1: No Irrigation Required
Same as prerequisite
๐ Eligible for maximum performance
โ Option 2: Reduced Irrigation
๐ Thresholds
- 50% reduction โ 1 point
- 100% reduction โ 2 points
โ ๏ธ Critical Rule (VERY TESTABLE)
๐ First 30% reduction MUST come from:
- plant selection
- irrigation efficiency
๐ Beyond 30%, you can use:
- alternative water (rainwater, graywater)
- smart controls
- advanced systems
๐ฏ Exam Insight
LEED = Efficiency First โ Then Alternative Water
๐ฟ Strategies to Achieve This Credit
๐ฑ 1. Native / Adaptive Plants
- require less water
- suited to local climate
๐ง 2. Efficient Irrigation Systems
Example:
๐ Drip Irrigation
- low-pressure system
- delivers water directly to roots
- minimizes evaporation
๐ต 3. Xeriscaping
๐ Landscaping that:
- requires little to no irrigation
โป๏ธ 4. Alternative Water Sources
- rainwater harvesting
- graywater reuse
- reclaimed water
๐ 5. Smart Irrigation Controls
- weather-based controllers
- soil moisture sensors
๐ 6. Submetering
- track irrigation use
- identify inefficiencies
๐ง Where People Get Confused
โ Misconception 1:
โAlternative water helps meet prerequisiteโ
๐ No
๐ First 30% must be from:
- efficiency + plant selection
โ Misconception 2:
โCredit and prerequisite are the sameโ
๐ No
- 30% โ prerequisite
- 50โ100% โ credit
โ Misconception 3:
โAll landscaped areas are included in calculationsโ
๐ No
๐ Only:
- vegetated areas count
Official FAQs
What is the minimum reduction required for the prerequisite?
What tool is used for calculations?
A project achieves 40% reduction using only efficient irrigation. Does it meet the prerequisite?
A project uses rainwater to achieve the first 30% reduction. Does it comply?
Must use:
โข efficiency + plant selection
Why does LEED require efficiency before alternative water?
โข reduces overall demand
โข ensures long-term sustainability
โข avoids over-reliance on systems
Comments
I really enjoyed reading about the Outdoor Water Use Reduction strategies! It reminded me of when I helped my friend landscape their backyard. We used native plants that required less water, and it not only saved on our water bill but also brought in a lot of local wildlife. I love how these sustainable practices can create such a positive impact both environmentally and aesthetically! Your tips on irrigation systems were super helpful tooโdefinitely adding those to my future gardening plans. Thanks for sharing this valuable Snow Rider 3D info!
I really enjoyed reading about the Outdoor Water Use Reduction strategies! It reminded me of when I helped my friend landscape their backyard. We used native plants that required less water, and it not only saved on our water bill but also brought in a lot of local wildlife. I love how these sustainable practices can create such a positive impact both environmentally and aesthetically! Your tips on irrigation systems were super helpful tooโdefinitely adding those to my future gardening plans. Thanks for sharing this valuable Snow Rider 3D info!