Page 107 - GRIHA Manual Volume II - Introduction to National Rating System
P. 107
Sustainable site planning 99
# The efficiencies of irrigation systems differ widely. Further, to improve the efficiency certain
measures can be followed, which includes use of a pressure regulator for pressures greater
than 30 psi which will significantly reduce the loss during watering. Efficiencies of different
kinds of irrigation equipment are given in the Table 1.
Table 1 Eficiency of irrigation equipment
Irrigation system Eficiency (%)
Micro, drip 85
Micro, spray 80
Multiple sprinkler 75
Sprinkler, large guns 70
Seepage 50
Crown lood 50
Flood 50
# Fixed time schedule for watering
Time schedule for watering of plants plays an important role in saving water. Irrigation should
be done during the coolest time of the day (early mornings and evenings) to avoid loss due to
evaporation and wind drift. Also, the frequency of irrigation should be reduced during the winters.
Regular flushing of the irrigation lines and other parts should be done.
The use of combination of mitigation options can result in savings of water as indicated in
Table 2. The table indicates the reduction in water that is possible by stepwise cutting down in areas
of high-water-consuming components. By reducing the lawn area by 50% and replacing it with
shrubs, it is possible to achieve 32% savings and by further introducing native species to the level of
25%, further increase in savings of 42% can be achieved.
Table 2 Estimate of savings in water
Options Savings in water (%)
100% lawn
50% lawn: 50% shrubs 32
50% lawn: 25%shrubs: 25% native 42
100% native 64
Source Manual on norms and standards for environment clearance of large construction projects—MoEF, Government of India
# Water quality standards for irrigation
The BIS standards for irrigation is indicated in Table Table 3 Standards for irrigation
3. It is important to conform to the prescribed Parameter for irrigation Standard
standards while using water from various sources Total dissolved solids (mg/litre) 2100
such as groundwater, municipal water, rainwater or Chlorides as chlorine (mg/litre) 500
treated water. Boron (mg/litre) 2
# Choosing appropriate type of irrigation system Sulphates (as SO 4 )(mg/litre) 1000
s
is essential for uniform distribution of water. Conductivity at 25 °C (m /cm) 2.25
Poor distribution of water is an indicator of pH 6.0–8.0
inefficiency in the irrigation system as it would Source National Building Code, 2005
lead to excessively wet or dry areas.
# The efficiencies of irrigation systems differ widely. Further, to improve the efficiency certain
measures can be followed, which includes use of a pressure regulator for pressures greater
than 30 psi which will significantly reduce the loss during watering. Efficiencies of different
kinds of irrigation equipment are given in the Table 1.
Table 1 Eficiency of irrigation equipment
Irrigation system Eficiency (%)
Micro, drip 85
Micro, spray 80
Multiple sprinkler 75
Sprinkler, large guns 70
Seepage 50
Crown lood 50
Flood 50
# Fixed time schedule for watering
Time schedule for watering of plants plays an important role in saving water. Irrigation should
be done during the coolest time of the day (early mornings and evenings) to avoid loss due to
evaporation and wind drift. Also, the frequency of irrigation should be reduced during the winters.
Regular flushing of the irrigation lines and other parts should be done.
The use of combination of mitigation options can result in savings of water as indicated in
Table 2. The table indicates the reduction in water that is possible by stepwise cutting down in areas
of high-water-consuming components. By reducing the lawn area by 50% and replacing it with
shrubs, it is possible to achieve 32% savings and by further introducing native species to the level of
25%, further increase in savings of 42% can be achieved.
Table 2 Estimate of savings in water
Options Savings in water (%)
100% lawn
50% lawn: 50% shrubs 32
50% lawn: 25%shrubs: 25% native 42
100% native 64
Source Manual on norms and standards for environment clearance of large construction projects—MoEF, Government of India
# Water quality standards for irrigation
The BIS standards for irrigation is indicated in Table Table 3 Standards for irrigation
3. It is important to conform to the prescribed Parameter for irrigation Standard
standards while using water from various sources Total dissolved solids (mg/litre) 2100
such as groundwater, municipal water, rainwater or Chlorides as chlorine (mg/litre) 500
treated water. Boron (mg/litre) 2
# Choosing appropriate type of irrigation system Sulphates (as SO 4 )(mg/litre) 1000
s
is essential for uniform distribution of water. Conductivity at 25 °C (m /cm) 2.25
Poor distribution of water is an indicator of pH 6.0–8.0
inefficiency in the irrigation system as it would Source National Building Code, 2005
lead to excessively wet or dry areas.
