Page 100 - GRIHA Manual Volume V - Introduction to National Rating System
P. 100
Evaluation procedure 93
4. review the drawings for delivery of treated wastewater and harvested rainwater for
intended application.
5. Carefully check the submitted calculation sheet for percentage water reuse and recharge
in the column for building water demand, aC cooling tower, and dg cooling tower water
demand , external washing, swimming pool, etc., if applicable, is also included (which is
otherwise not counted for in criterion 11: reduce the water use by building).
6. review the filtration system provided and check it against the intended application for
reuse/recharge.
Possible errors
1. rainwater harvesting potential calculation and actual design of storage structures
data should be clear enough. Capacity of the storage structures and their potential use
application for potable/non-potable purpose should be clearly given.
2. in this case, the water requirement for building will be inclusive of all the potable and
non-potable water requirements, such as toilet flushing, external washing, cooling towers,
drinking, cooking, bathing, and so on. in the calculation sheet, these numbers may be taken
directly from the value calculated in criterion 11 alone, which is not correct.
3. if rainwater is proposed to be used for building use/landscaping application as well as
recharge, carefully check all the numbers, such as total rainwater harvested, rainwater
being used for building/landscape application and recharging.
4. dual plumbing system may be missing though the calculation sheet shows intended
treated water and rainwater reuse.
5. Site-specific conditions must be carefully studied to ensure the suitability of harvesting
rainwater for storage and/or recharge.
Point allocation
one point should be awarded if all compliance documents (21.2.1 to 21.2.5) are adequate and meet
the griha requirements, and the calculation sheet shows annual water reuse of 25% or more.
one more point should be awarded if the calculation sheet shows annual reuse of 50% or more.
one more point should be awarded if the calculation sheet shows annual reuse of 75% or more.
Appraisal 21.3.4
recharge of surplus rainwater into aquifer (2 points)
Required documentation
1. Calculation sheet showing the percentage of harvested water going for recharge.
2. details of filtration system for rainwater harvesting.
Review checklist
1. Carefully review the adequacy of recharging in the given site as it is a site-specific condition.
2. Check the adequacy of the filtration system depending on the silt level, possible
contamination, catchment area, and so on.
4. review the drawings for delivery of treated wastewater and harvested rainwater for
intended application.
5. Carefully check the submitted calculation sheet for percentage water reuse and recharge
in the column for building water demand, aC cooling tower, and dg cooling tower water
demand , external washing, swimming pool, etc., if applicable, is also included (which is
otherwise not counted for in criterion 11: reduce the water use by building).
6. review the filtration system provided and check it against the intended application for
reuse/recharge.
Possible errors
1. rainwater harvesting potential calculation and actual design of storage structures
data should be clear enough. Capacity of the storage structures and their potential use
application for potable/non-potable purpose should be clearly given.
2. in this case, the water requirement for building will be inclusive of all the potable and
non-potable water requirements, such as toilet flushing, external washing, cooling towers,
drinking, cooking, bathing, and so on. in the calculation sheet, these numbers may be taken
directly from the value calculated in criterion 11 alone, which is not correct.
3. if rainwater is proposed to be used for building use/landscaping application as well as
recharge, carefully check all the numbers, such as total rainwater harvested, rainwater
being used for building/landscape application and recharging.
4. dual plumbing system may be missing though the calculation sheet shows intended
treated water and rainwater reuse.
5. Site-specific conditions must be carefully studied to ensure the suitability of harvesting
rainwater for storage and/or recharge.
Point allocation
one point should be awarded if all compliance documents (21.2.1 to 21.2.5) are adequate and meet
the griha requirements, and the calculation sheet shows annual water reuse of 25% or more.
one more point should be awarded if the calculation sheet shows annual reuse of 50% or more.
one more point should be awarded if the calculation sheet shows annual reuse of 75% or more.
Appraisal 21.3.4
recharge of surplus rainwater into aquifer (2 points)
Required documentation
1. Calculation sheet showing the percentage of harvested water going for recharge.
2. details of filtration system for rainwater harvesting.
Review checklist
1. Carefully review the adequacy of recharging in the given site as it is a site-specific condition.
2. Check the adequacy of the filtration system depending on the silt level, possible
contamination, catchment area, and so on.
