Climate change has become a global issue right now. Concerns raised from these issues has insisted people to adopt the sustainable development.

Because water is one of the world’s most necessary natural resources, all green building projects should include water efficiency as a mainstream goal. 

The demand of fresh water is going to be double in next 30 years.

Keeping all such concerns in mind LEED has implemented a credit named Water Efficiency in their green building certification system.

Water Credit in LEED

The main aim of this credit is to make reduction in the water usage. Management of rainwater is also favoured.

The employment of alternative, no potable water sources is done for appropriate end uses.

In LEED v4.1 for Building Design and Construction (BD+C) following prerequisites are required

Outdoor Water Use Reduction (1–3 points)

This credit applies to

· New Construction (1–2 points)

· Core & Shell (1–3 points)

· Schools (1–2 points)

· Retail (1–2 points)

· Data Centers (1–2 points)

· Warehouses & Distribution Centers (1–2 points)

· Hospitality (1–2 points)

· Healthcare (1 point)

In this credit show that

Landscape does not require a permanent irrigation system beyond a maximum two-year

Establishment period.

Or

Reduce the project’s landscape water requirement (LWR) by at least 50% from the calculated baseline for

The site’s peak watering month.

Points for reducing irrigation water

Percentage reduction from baseline	Points (except Healthcare)	Points (Healthcare)	Points (CS)
50%	1	1	1
75%	—	—	2
100%	2	—	3

Indoor Water Use Reduction and (1–7 points)

This credit applies to

· New Construction (1–6 points)

· Core & Shell (1–4 points)

· Schools (1–7 points)

· Retail (1–7 points)

· Data Centers (1–6 points)

· Warehouses & Distribution Centers (1–6 points)

· Hospitality (1–6 points)

· Healthcare (1–7 points)

Points for reducing water use

Percentage Reduction	Points (BD+C)	Points (CS)	Points (Schools, Retail, Hospitality, Healthcare)
25%	1	1	1
30%	2	2	2
35%	3	3	3
40%	4	4	4
45%	5	—	5
50%	6	—	—

Building-level Water Metering (1 point)

This credit applies to

· New Construction (1 point)

· Core & Shell (1 point)

· Schools (1 point)

· Retail (1 point)

· Data Centers (1 point)

· Warehouses & Distribution Centers (1 point)

· Hospitality (1 point)

· Healthcare (1 point)

The intent of this to support water management and identify opportunities for additional water savings by tracking water

Consumption.

The Water Efficiency in LEED v4.1 BD+C consider following Priorities

• Water Sense-certified appliances, low-flow fixtures are to be used to reduce indoor water use.

• Installation of permanent water meters that measure the total potable water use for the project; also submeter has to be installed at water subsystems.

• A new option is provided in the former Cooling Tower Water Use credit for mechanical processes. This credit encourages the recycling and reuse of no potable water for cooling and mechanical building needs.

• Irrigation of outdoor spaces must be shown to either be unnecessary or to be reduced by at least 30% from typical figures, through the selection of native or adapted plants for landscaping, alternative water sources for irrigation or irrigation efficiency measures.

An example of SLD of water metering is shown below