Page 111 - GRIHA Manual Volume II - Introduction to National Rating System
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Sustainable site planning 103
10.2 Compliance
The following documents are to be submitted.
10.2.1 Narrative demonstrating water-saving measures adopted in the landscape plan.
10.2.2 Plan indicating the plants list, nature of species, and area covered.
10.2.3 Calculation of the water requirements after establishment for landscape in litres per day
(LPD) for each month due to variation in ET rate.
10.2.4 Provide cut sheets of the irrigation equipment showing technical specifications, such as
flow rate and dimensions.
10.3 Appraisal (maximum points – 3)
10.3.1 Reduction in water consumption by 30%, as per clause 10.2.3 (1 point).
10.3.2 Reduction in water consumption by 40%, as per clause 10.2.3 (1 point).
10.3.3 Reduction in water consumption by 50%, as per clause 10.2.3 (1 point).
Methodology
Step 1: Calculate the annual landscape water demand for the
designed case L design
Designed case is defined as the original proposed landscape scheme with the plant distribution,
irrigation system efficiencies, as proposed by the consultant.
Calculate the landscape water demand for all the months for the designed case and then add up
to get the annual landscape water demand.
Step 2: Calculate the annual landscape water demand for the base
case L base
Base case is defined as the total landscaped area assumed to be covered with lawns (which has
highest plant factor). Also, the irrigation system efficiency is assumed as 0.75 for the base case as
conventional sprinklers are used for irrigating lawns.
Calculate the landscape water demand for all the months for the base case and then add up to
get the annual landscape water demand.
Step 3: Calculate the percentage reduction in water demand
Reduction in water demand (%) = (L base – L design /L base ) × 100
Calculating landscape water demand using landscape water demand
calculator
The sequential steps to be followed for arriving at the landscape water demand is given in
this section.
The water requirement of the landscape can be estimated using the following equation.
Canopy area(m )x Evapotranspiration rate (m)x Plant factor x 1000
2
Water requirement (lpd) =
Irrigation system efficiency
10.2 Compliance
The following documents are to be submitted.
10.2.1 Narrative demonstrating water-saving measures adopted in the landscape plan.
10.2.2 Plan indicating the plants list, nature of species, and area covered.
10.2.3 Calculation of the water requirements after establishment for landscape in litres per day
(LPD) for each month due to variation in ET rate.
10.2.4 Provide cut sheets of the irrigation equipment showing technical specifications, such as
flow rate and dimensions.
10.3 Appraisal (maximum points – 3)
10.3.1 Reduction in water consumption by 30%, as per clause 10.2.3 (1 point).
10.3.2 Reduction in water consumption by 40%, as per clause 10.2.3 (1 point).
10.3.3 Reduction in water consumption by 50%, as per clause 10.2.3 (1 point).
Methodology
Step 1: Calculate the annual landscape water demand for the
designed case L design
Designed case is defined as the original proposed landscape scheme with the plant distribution,
irrigation system efficiencies, as proposed by the consultant.
Calculate the landscape water demand for all the months for the designed case and then add up
to get the annual landscape water demand.
Step 2: Calculate the annual landscape water demand for the base
case L base
Base case is defined as the total landscaped area assumed to be covered with lawns (which has
highest plant factor). Also, the irrigation system efficiency is assumed as 0.75 for the base case as
conventional sprinklers are used for irrigating lawns.
Calculate the landscape water demand for all the months for the base case and then add up to
get the annual landscape water demand.
Step 3: Calculate the percentage reduction in water demand
Reduction in water demand (%) = (L base – L design /L base ) × 100
Calculating landscape water demand using landscape water demand
calculator
The sequential steps to be followed for arriving at the landscape water demand is given in
this section.
The water requirement of the landscape can be estimated using the following equation.
Canopy area(m )x Evapotranspiration rate (m)x Plant factor x 1000
2
Water requirement (lpd) =
Irrigation system efficiency
