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G E O F L O W ™ S U B S U R F A C E I R R I G A T I O N S Y S T E M S
A S A P P L I E D T O O N - S I T E E F F L U E N T D I S P O S A L O F
W A S T E W A T E R .
D E S I G N A N D I N S T A L L A T I O N M A N U A L
1. INTRODUCTION
Effluent disposal and irrigation are hydraulically similar but the design requirements are not identical. With effluent
disposal the aim is usually to dispose of the effluent using the minimum area as quickly and safely as possible at an
approximately uniform rate throughout the year. A disposal system has to keep operating in the rain, while an irrigation
system does not. With irrigation the aim is usually to optimise the use of water over as large an area as possible with
allowance for a wide range of water usage between seasons.
IF THE MAIN PURPOSE OF THE GEOFLOW SYSTEM IS TO IRRIGATE, THEN PLEASE USE THE STANDARD
IRRIGATION DESIGN MANUAL FOR LANDSCAPE & TURF.
Subsurface drip is the most efficient method to dispose of effluent. Precise amounts of water are applied under the soil
surface. The main advantages of subsurface irrigation for effluent disposal are:
• Minimises health risk
• Well designed systems will not cause puddling or runoff.
• Even uniformity over the entire disposal area.
• Can be used under difficult circumstances of high water tables, tight soils, steep slopes or wind.
• Maximises disposal of water by means of evapotranspiration by the plants.
• Minimises deep percolation.
• Increases consumption of nitrates by the plant material.
• Invisible and vandal proof installations.
• Durable systems with no moving parts for a long life.
• Non intrusive. It allows use of the space while in operation.
• Easily automated.
Subsurface drip irrigation systems have been used in both agriculture and landscaping for over 20 years. Subsurface drip
is becoming more popular everyday because of the agronomic and ecological advantages.
The critical factors for subsurface drip to succeed with biologically active water is a well designed, reliable installation and
management control. The basis of any design is knowing how much water the treatment system will produce, and how
much water can be applied per m2 on a daily basis. This may mean testing each site for absorption rates.
2. SYSTEM COMPONENTS:
A typical drip system installation will consist of the elements listed below:
WASTEFLOW™ Lines (or emitter lines)
These lines carry the water into the area to be irrigated. WASTEFLOW™ lines are connected to the submain and flush
lines usually with grommet - barbed fittings. (In small systems < 1500 l/hr capacity through the system, the actual
Wasteflow tube can be used for submain & flushing lines). The emitters are "in" the line. With WASTEFLOW™
Classic
the flow rate delivered by the emitter is a function of the pressure at the emitter. At 100 Kpa the flow rate is 4.0 l/hr.
With WASTEFLOW™
PC
the flow rate will be constant 2.4 l/hr at pressure ranging from 50 - 400 kPa.
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Copyright Geoflow Inc. 1999.