An economical choice for manual stream gauging and calculations.

The Gurley Model 1100 Digital Indicator contains CMOS circuitry to convert opto-electronical pulses from the meter to direct display of flow velocity. The unit offers three user-selectable modes:

Automatic: for four-second sampling time, with readout in either feet per second or meters per second.

Automatic averaging: with velocity averaged over a sixteen-second period, for especially turbulent flows.

Manual: for independent measurement of both elapsed time and bucket wheel revolutions.

Other features and advantages include hand-held and self-contained enclosure, as well as built-in diagonostics which verify proper operation. 

Model 1100 Conversion Kits

Upgrade headphone style outfits to digital.

These kits contain everything needed to convert a headphone type meter to digital readout. Kits for rod suspended outfits include a 15 foot sensor assembly. Those for cable suspension outfits include a 50 foot suspension cable and a 18 inch sensor assembly. All kits contain the Model 1100 Digital Indicator plus the appropriate hub extension, rotor housing, adjusting pin, sensor head plug and current meter cap for the outfit.

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Upgrade headphone and optical style outfits to compute total flow.

Features and advantages include:

  • more efficient stream flow calculations (an average of 20 minutes per cross-section)

  • reduces operator error by automatically computing formulas

  • weather resistant

  • standard computer output is similar to USGS' 'black sheet'

  • optional software can plot data in graph format

The AquaCalc 5000 is a handheld device that measures, records and calculates velocity and total flow measurements.  The user inputs the distance and depth, while the AquaCalc measures the revolutions and time, thus calculating the velocity and total discharge. 

Optional accessories include:

  • Rod mount: attaches the indicator to a top-setting wading rod

  • Advanced firmware - this upgrade includes additional procedures requested by the USGS to: 

  • 1) improve accuracy in troublesome conditions

  • 2) add/delete stations while testing

  • 3) extended vertical measurements

  • 4) perform ice measurements

  • 5) display available memory 

  • 6) recognize incorrect meter and/or sounding weight used.