Pearl Building Rating System - Estidama

IS=Total annual average irrigation demand of all external softscape areas (liters/day)
Note: Areas associated with school playing fields are excluded from the average
landscape irrigation requirement calculation.
Irrigation System
A water efficient irrigation system must:
� Eliminate all surface spray components (except in public parks or playing fields);
� Irrigate only during non-daylight hours (except if sub-surface);
� Include moisture sensors that control the irrigation system to irrigate only when
required;
� Provide irrigation zones, with independently controlled valves, segregated by plant
water needs; and
� Utilize mulch and/or soil amendment techniques to reduce evapotranspiration.
Irrigation System Management
An Irrigation Operation and Maintenance Plan should include:
� Regular maintenance and operation efficiency performance monitoring;
� Procedures for alerting operator and shutting system down when flows exceed
design range due to mainline, lateral, valve or emitter failure or there is a leak
detected; and
� Irrigation systems must demonstrate that they incorporate sensors and valves
connected to a central system by:
� Providing override sensors tied to a centralized computer controller with a
feedback loop to shut down zones that are malfunctioning; and
� Including separate meters and backflow prevention at point of mainline
connection.
Recycled Water
The Exterior Water Allowance, EWA, is based on achieving a water balance between the
building wastewater and the project’s exterior uses (irrigation, heat rejection and
water features). It is a notional value that represents the amount of water that is
allowed for exterior uses. Although recycled water may not physically be used for the
project’s exterior demand, it is offsetting the potable demand of exterior uses within
the Emirate of Abu Dhabi and therefore the focus is placed on achieving this balance
irrespective of whether recycled water is physically used.
Note: This offset approach only applies to exterior uses. To document reductions in
potable water within the building (as in PW-1), recycled water must physically be used
within the building in order to achieve reductions attributed to recycled water.
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