2.11 Irrigation for Landscaping
Application Rates. The system shall be designed to
minimize surface run-off. In heavy clay soils, a low
application rate may be required. Overspray onto paved
System Design
surfaces should be avoided.
Controls. Irrigation controls should be easily understood
General Criteria. An irrigation system (if required) will
by maintenance personnel. The designer should coordi-
provide water to plants only when needed. High-efficiency
nate with the Building Manager as to the appropriate
irrigation technologies, such as drip irrigation, should be
controls. Provide automatic controls to allow for
used. Care will be taken so that water can be conserved
scheduling of watering times for late night and early
through the use of a properly designed irrigation system.
morning to reduce water losses due to evaporation.
Non-potable water should be used as a source for the
Rain sensors or soil moisture sensors are essential to
irrigation system when it is available.
prevent unnecessary watering. Freeze sensors should be
Reliable performance must be a prime goal in the design
provided for systems in cold climates.
of irrigation systems. Materials will be durable and
relatively maintenance free. Irrigation systems will be
Maintenance Considerations. All major components shall
most successful in the long run if local design practices
be installed in protected, accessible locations. Controllers
are followed and locally available materials are used.
and remote sensing stations should be placed in vandal-
proof enclosures. Above-ground components, such as
Allow for expansion of the irrigation system, both in area
backflow preventers, shall be placed in unobtrusive
and in flow rate, so the system can be adjusted as plants
locations and protected from freezing.
mature.
Quick coupling valves should be of two-piece body design
Metering. Irrigation water should be metered separately
and installed throughout the system to allow for hosing
from domestic water to avoid expensive user sewage fees.
down areas and to permit easy access to a source of water.
Locate drain valves to permit periodic draining of the
Zoning. Irrigation systems shall be zoned so different
system.
areas can be watered at different times. Avoid mixing
different head or nozzle types (such as a spray head and
a bubbler) on the same station. Different types of
vegetation, such as turf and shrub areas, should also
not be placed on the same station.
44 F A C I L I T I E S S T A N D A R D S
FOR THE
PUBLIC
BUILDINGS
SERVICE
2.11 Irrigation for Landscaping
Revised March 2005 PBS-P100
Previous Page
