INDIVIDUAL RESIDENTIAL SPRAY IRRIGATION SYSTEM

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INDIVIDUAL RESIDENTIAL SPRAY IRRIGATION SYSTEM

• by
• Albert Jarrett,
• Professor of Agricultural Engineering

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The Pennsylvania Protocol

• In Chapter 73 (Conventional).
• In-Ground Systems (Limiting Zone gt60 in).
• Beds.
• Trenches.
• Subsurface Sand Filters.
• Elevated Sand Mounds (Limiting Zone gt20 in).
• Individual Residential Spray Irrigation System
• Bedrock Limiting Zone gt 16 in.
• Water Table Limiting Zone gt10 in.

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Soil Conditions

• Bedrock Limiting Zone gt 16 inches.
• Water Table Limiting Zone gt 10 inches.

gt 16 inches
gt 10 inches
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IRSIS Overall System(top view)
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IRSIS Overall System(side view)

• Four Major Components

Treatment Tank
Chlorine Disinfection
Spray Area
Filtration
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Treatment Processes

• From Home to Treatment Tank.
• Septic Tank
• Solids settle
• Scum floats to surface
• Two Chamber Septic Tanks required.

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Treatment Tank

• Septic Tank
• Aerobic Tank

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Treatment Processes

• From the Treatment Tank to the Filtration Unit.
• Three types of Filtration Units (or
  Pre-Treatment) have been approved.
• Free Access Sand Filter
• Subsurface Sand Filter
• Peat Bio-Filter

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Free Access Sand Filter (side view)
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Free Access Sand Filter (top view)
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Subsurface Sand Filter (partial side view)
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Subsurface Sand Filter(top view)
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Peat Bio-Filter
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Peat Bio-Filter
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Treatment Processes

• From the Filtration Unit to the Chlorine
  Disinfection.
• Two types of Chlorine Injection Units have been
  approved
• Erosion Tablet Units
• Hypochlorite Units.
• These units inject chlorine into the wastewater.

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Erosion Chlorine Tablet Units

• Advantages
• No Moving Parts
• Low Maintenance
• Less Expensive
• Disadvantages
• Difficult to Calibrate.
• Bridging of Tablets.

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Hypochlorite Unit

• Advantages
• Does not Bridge.
• Easy to Calibrate.
• Disadvantages
• Moving parts.
• More Expensive.
• Tubing can clog.
• High Maintenance.

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Treatment Processes

• Following the injection of Chlorine into the
  wastewater, the wastewater flows into a large
  storage tank.
• The storage tank serves two purposes.
• Opportunity for Chlorine contact.
• Storage during inclement weather.

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Storage Tank and Chlorinator(side view)
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Storage Tank and Chlorinator(top view)
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Treatment Processes

• After the chlorine has been injected into the
  wastewater, the wastewater must set in a
  container for a period of time.
• The goal is to provide adequate time for the
  chlorine to kill any bacteria remaining in the
  wastewater.
• Following this contact time, a residual of 0.2 to
  2.0 ppm of Cl must remain in the water.

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Storage Tank

• A portion, usually at least 6 inches depth, of
  the storage tank is permanent
• This depth is never pumped to
• Ensure Chlorine contact.
• Protect the pump.

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Storage Tank

• The depth of water above the permanent depth is
  to store the daily wastewater flow from the home.
• This volume is also available for Chlorine
  contact.

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Storage Tank

• The depth above the daily flow volume is required
  to provide several days of storage incase weather
  conditions are not suitable for irrigating the
  wastewater on any given day.

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Spray Irrigation

• After midnight, each day, the pump should
  activate and the daily wastewater volume should
  be pumped to the spray area.
• If the weather is inclement, this can be delayed
  for a day or so.

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Spray Irrigation Area
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Each Sprinkler
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IRSIS For You??

• This overview of the IRSIS On-Lot Sewage System
  may have raised some questions.
• If you would like more information about IRSIS,
  get ABE Fact Sheet F-16? Or
• Contact your Sewage Enforcement Officer (SEO), or
• Contact your County Agent.

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Thank You