Wells and Piezometers

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Wells and Piezometers
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Cap with vent hole
Solid PVC (2 minimum)
Landscape Fabric - optional
Well
Piezometer
Slotted or Drilled PVC
Cap with vent hole at bottom
Open at bottom covered with fabric
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Typical Wells
Cap and vent hole
Annulus

Solid pipe
Bentonite
Restrictive Layer
Slotted pipe
Sand
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Measurement Methods

• Manual
• Chalked Tape
• Audio-electric
• Semi-recording
• Maximum Level Device
• Recording
• Paper
• Electronic

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Beeper
Closed Cir. Jack
SPST Switch
Bare wires
Weight
Insulated wires
Lamp
Phone plug
Buzzer
9 v Battery
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Maximum Level Device
3/16 METAL ROD
WELL CASING
MAGNET
FLOAT
WASHER
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Examples
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Piezometers
Well
Sand
Perched Water Table
Clay
Sand
Shallow piezometer contains water, but lower
piezometer does not. Perched water table
detected.
Water drains down well, Saturation undetected
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Soils Considerations

• Complete a profile description for each site
  where equipment will be installed.
• Estimate the depth to any layers that may perch
  water for long periods.
• From the description estimate the depths that
  wells will be installed

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Determining flow with wells and piezometers
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No Flow Conditions
W1
W2
P1
P2
Slotted Pipe
Solid Pipe
P1W1P2W2
No Flow
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Discharge Conditions
W1
W2
P1
P2
P1gtW1 P2gtW2
Flow up
P1gtP2 Flow is left to right
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Recharge Conditions
W1
W2
P1
P2
W1gtP1 W2gtP2 Flow down P2gtP1 Flow is right
to left
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