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92 Griha Manual: Volume 5
21.3 Appraisal (maximum points-5)
21.3.1 annual water reuse of 25% as per clause 21.2.4 (1 point).
21.3.2 annual water reuse of 50% as per clause 21.2.4 (1 point).
21.3.3 annual water reuse of 75% as per clause 21.2.4 (1 point).
21.3.4 recharge of surplus rainwater into aquifer (2 points).
Non-applicability condition
The irst three appraisal points shall not apply to projects that have wastewater generation on site less than 10 kL/day. The fourth
and ifth appraisal points shall not apply to projects in which the groundwater table is high and recharge of rainwater into the ground
is not advisable as per the Central Ground Water Board (CGWB) norms.
Water reuse is applicable only if provision for on-site wastewater treatment is technically and inancially feasible. As explained
in the earlier criterion, site generating less than 10 kL per day of wastewater may not necessarily opt for treatment of the
wastewater. Subsequently, in absence of any treatment there are no alternatives for wastewater reuse (not even for irrigation due
to health hazards). Therefore, 21.3.1, 21.33.2, and 21.3.3 are not applicable to such sites.
Subsequent appraisal 21.3.4 is subject to site-speciic conditions. Sites having high water table are liable to looding if provided
with water recharging facility. Similarly, sites which sit, on hard rocks or have clayey soil (such soils have very low iniltration of
water) cannot take rainwater for recharging. Refer to guidelines given by the CGWB in the Manual on Artiicial Recharge of Ground
Water for better understanding of non-applicability conditions. Thus, based on the hydro-geological conditions, groundwater
level, and other constraints, it may not be feasible to recharge rainwater in certain sites. Therefore, such sites shall fall under the
category of non-applicability condition.
Evaluation procedure
Appraisal 21.3.1, 21.3.2 and 21.3.3
21.3.1 annual water reuse of 25%, as per clause 21.2.5 (1 point).
21.3.2 annual water reuse of 50%, as per clause 21.2.5 (1 point).
21.3.3 annual water reuse of 75%, as per clause 21.2.5 (1 point).
Required documentation
1. drawings, specifications, and write-up on wastewater treatment system along with
rainwater harvesting system (storage and/or recharge systems) details.
2. dual plumbing system drawings with specifications.
3. drawing showing delivery lines for treated wastewater and harvested rainwater.
4. Calculation sheet showing the percentage water reuse (within building and landscaping)
and percentage of harvested water going for recharge.
5. details of filtration system for rainwater harvesting.
Review checklist
1. review the submitted drawings and write-up on wastewater treatment systems along with
the rainwater harvesting systems in entirety. Carefully check the details of rainwater storage
and/or harvesting systems along with filtration systems.
2. review the submitted dual plumbing system if applicable in the proposed project and
match it with the proposed application.
3. Check the proposed quality of treated wastewater with the proposed application as per the
standards.
21.3 Appraisal (maximum points-5)
21.3.1 annual water reuse of 25% as per clause 21.2.4 (1 point).
21.3.2 annual water reuse of 50% as per clause 21.2.4 (1 point).
21.3.3 annual water reuse of 75% as per clause 21.2.4 (1 point).
21.3.4 recharge of surplus rainwater into aquifer (2 points).
Non-applicability condition
The irst three appraisal points shall not apply to projects that have wastewater generation on site less than 10 kL/day. The fourth
and ifth appraisal points shall not apply to projects in which the groundwater table is high and recharge of rainwater into the ground
is not advisable as per the Central Ground Water Board (CGWB) norms.
Water reuse is applicable only if provision for on-site wastewater treatment is technically and inancially feasible. As explained
in the earlier criterion, site generating less than 10 kL per day of wastewater may not necessarily opt for treatment of the
wastewater. Subsequently, in absence of any treatment there are no alternatives for wastewater reuse (not even for irrigation due
to health hazards). Therefore, 21.3.1, 21.33.2, and 21.3.3 are not applicable to such sites.
Subsequent appraisal 21.3.4 is subject to site-speciic conditions. Sites having high water table are liable to looding if provided
with water recharging facility. Similarly, sites which sit, on hard rocks or have clayey soil (such soils have very low iniltration of
water) cannot take rainwater for recharging. Refer to guidelines given by the CGWB in the Manual on Artiicial Recharge of Ground
Water for better understanding of non-applicability conditions. Thus, based on the hydro-geological conditions, groundwater
level, and other constraints, it may not be feasible to recharge rainwater in certain sites. Therefore, such sites shall fall under the
category of non-applicability condition.
Evaluation procedure
Appraisal 21.3.1, 21.3.2 and 21.3.3
21.3.1 annual water reuse of 25%, as per clause 21.2.5 (1 point).
21.3.2 annual water reuse of 50%, as per clause 21.2.5 (1 point).
21.3.3 annual water reuse of 75%, as per clause 21.2.5 (1 point).
Required documentation
1. drawings, specifications, and write-up on wastewater treatment system along with
rainwater harvesting system (storage and/or recharge systems) details.
2. dual plumbing system drawings with specifications.
3. drawing showing delivery lines for treated wastewater and harvested rainwater.
4. Calculation sheet showing the percentage water reuse (within building and landscaping)
and percentage of harvested water going for recharge.
5. details of filtration system for rainwater harvesting.
Review checklist
1. review the submitted drawings and write-up on wastewater treatment systems along with
the rainwater harvesting systems in entirety. Carefully check the details of rainwater storage
and/or harvesting systems along with filtration systems.
2. review the submitted dual plumbing system if applicable in the proposed project and
match it with the proposed application.
3. Check the proposed quality of treated wastewater with the proposed application as per the
standards.
