PUMP TYPES. Pump Sizing. Dose to Gravity. Pumping to Gravity Distribution. Systems that need a Lift. Distribution Box and Tiered Trenches.

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1 PUMP TYPES Sump Clean Water Only Systems that need a Lift Effluent Multi stage Single stage Sewage Grinder Pumping to Gravity Distribution When STA is at higher elevation than septic tank Pump Sizing TDH Set by Location Impacted by flow GPM gpm Dose to Gravity Distribution Box and Tiered Trenches Do not pump downhill Does not result in uniform distribution in laterals Can discharge to either parallel or sequential network. Think about this before installing..

2 Pressure Manifold Pressure Distribution Designed to distribute effluent uniformly over infiltrative surface of receiving component. Pumping to Pressure Distribution Pressure Distribution Uses a network of small diameter pipe [1-2 ] and small orifices [1/8-1/4 ] NSFC The Right Pump for Pressure Distribution TDH Set by GPM Elevation Flow Rate Pipe Diameter Distribution Set by Number of orifices [6-10 sqft per orifice] Orifice size Operating pressure System Curve Pump Curve System Curve How Pump Works Elevation Head Pipe Friction Manifold Loss Where it Operates Pump Efficiency tdh Pump & System Curves gpm hp Pump 1.0 hp Pump System Curve at El 0 System Curve at El +5

3 Pressure Distribution Design considerations May use flow-splitting devices to minimize pump size Pump Vault Pumping from the Source Outside: In the System The pump Sizing Location Maximum Volume The floats The Electrical The controls The Sump Venting Pump Applications Media Filter

4 Pump Tank What size tank? Capacity Dose volume PLUS Storage Or Two Pumps Replaces storage Every Pump Should Be: Accessible Replaceable Wired Properly Elevated Controlled Accessible Access from surface Under the manhole Manhole to the surface Quick disconnect Not Fernco Reachable Within 20 of the surface Control Panel Line of Site Nuisance Replaceable Removable Pump Floats Ability to lift the pump Reconnecting the pump Electrician? Reconnecting the controls Pump Wiring In & out of the Tank Conduit [1-2 ] Electrical components sealed and watertight? Safe in the Sewage environment, EXCEPT FOR SPLICES!! Electrical tape is not watertight

5 Venting Be careful All electrical should be sealed If necessary vent thru a filter for odors Electrical The right size wire Pump size [hp] Distance Separate Circuits Pump Alarm Wiring Pump should be: Be careful of the power Hard conduit around the tank Elevated off bottom Storage Covered with effluent Protection Pump Basin [Elevated] Controlled Demand Piggy back Floats Timed Make sure the floats do not rest on the basin lip

6 Demand Dosing Dose occurs when sufficient volume of effluent has been collected. Dosing frequency depends on how much wastewater is being generated. There is no control on how much effluent is being dosed daily. Demand Dosing Two or Three floats On level sets the volume Check valve holds effluent in the piping Off level above the pump Water Level Sensors Float Pressure The Floats [Controls] Activation angle Voltage Wet Float Switches Mercury Float Switch Mechanical Float Switch Sensor Attachment Sensor can be: Tethered to float tree Weighted tether from riser Attached to bracket on riser

7 Float Tree Dose Volume (DV) Maximum~ Daily flow = 150 gal Minimum~ 4 times piping volume* Example: 3 trenches w/40 of 1.5 pipe 3 x 40 x 0.10 gal/ft 12 gal x 4 = 48 gals * Some sources say 5X piping volume Drawdown and Dose Volume Drawdown (in) = Dose Volume (gallons) GPI (gallons per inch) of drawdown Where: GPI = Area of dosing tank or chamber (in square ft) x ft x 7.5 gal/ft 3 Note: 1 = ½ ft or ft Area = length X width (of dosing chamber or dose tank) Calculating Drawdown Surface Area Rectangle: 4 x 7 tank L x W = Area 4 x 7 = 28 ft 2 Circle: 4 diameter Radius is half of diameter 4 2 = 2 Π x [radius] 2 = 3.14 x r x r 3.14 x 2 x 2 = 12.5 ft 2 Width= 4 Length= 7 Diameter = 4 Radius = 2 Top View Gallons Per Inch Area x x 7.5 gal/ft 3 = gal/inch 28 ft 2 x x 7.5 gal/ft 3 = 17.5 gal/in 12.5 ft 2 x x 7.5 gal/ft 3 = 7.8 gal/in Dose Volume (DV) Drawdown (in) = Dose Vol. GPI Dose volume ~ 100 gal Drawdown = 100 gal 17.5 gal/in 5.7 Plan View

8 Typical Pipe Volume Table Water Content (per ft. pipe) Nominal Pipe Size (in) Volume Weight (lbs.) (cu. in) (gallons) 1/ / / / / / / Without a Check Valve 100 gal Pumped Volume= PV Must subtract the drain back Drain back = Volume of pipe Drain back = Volume/LF x LF of pipe Ex: 60 of 2 inch pipe Drain back = 60 ft x 0.17 gal/ft = 10.2 gal Dose Volume = PV Drain back DV = 100 gal 10.2 gal = 89.8 gal that reaches the STA Floats Float Switch or Pump Cover ~ Off = 20 Dose~ On = 25.7 Alarm = 28.7 Piggy back Low cost Controlled by volume only Easy wiring Timers Timed Dosing A timer controls the number of doses per day and the dose volume. Will allow only a certain amount of effluent to be dosed daily. Protects downstream components from overloading. Useful for controlling surges or big-flow days.

9 Functions Off [Float] Turns timer off On Timer operates the pump Alarm Audible Visual Alarm Turns on the alarm Peak Enabler Changes the dosing frequency (PLC) Lateral Cleanouts Filter With ump Flushing Lateral PVC Lateral End w/ Clean-Out Valve Valve Types Box Orifice Shields To Soil Straight ends Threaded Pump Basin caps Ball valves Sweep 90 degree elbows (electrical sweeps are pressure rated) 2-45 degree 2" Sand elbows Leveling Layer Optional Lateral/Flushing Valve Connections Sand Backfill Sweep 2-45 Equipment Selection Don t let supplier select your equipment Better to talk to manufacturer Questions? DON T change components specified in design without consulting the designer; you are accepting liability

10 Low-Pressure Distribution Drainfield Shallow Narrow Drainfield Orifices in Laterals: Lay out and number the laterals Use a string line to mark pipe Pay attention to orientation and spacing Location of first/last orifice in each lateral may vary Drilling Orifices Pressure System Orifice Shields Use a new bit Use the correct size Keep media away from orifice Follow manufacturer recommendations Keep the drill vertical Don t wallow or it will be too large Orifice shape affects flow

11 Little to no slope Spacing and size of delivery devices Level sites: orifice size and spacing is typically the same in each lateral Spacing of delivery devices Sloping sites: spacing may vary to maximize uniformity CAUTION: if diameter varies, smaller orifices may clog more quickly Slope Balancing Unlevel Distribution Separate Pieces Goal: Splitting the flow equally Level ~Easy Problem Typically equal Separate pumps Alternating Splitter valves Hydro Splitter (ADV) Using Valves Balancing the pressure

12 Flow Regulating Valves Valve Boxes Adding one increases friction loss Globe valve is best but most expensive Gate valve is better Should NOT be a ball valve Design Questions? Orifice spacing and sizing Sprays to the same height Lower laterals Higher pressure Smaller holes Larger spacing