Staff (Head) Gauges

Openchannelflow’s freestanding Staff (Head) Gauges provide a quick and inexpensive way to visually check liquid level, the rise / fall of liquid over time, or water flow rate.  

Best practices for water level monitoring stations suggest a gauge be installed so that a visual comparative check can be made against the data loggers / stage indicators' measurement.

Gauge Terminology

The terms staff gauge and head gauge are interchangeable.  As is the spelling of gauge and gage - the latter being a spelling resulting from the USGS (who also use the term streamgage).

Where STAFF (HEAD) GAUGES ARE USED

• Creeks, streams, and rivers on watersheds
• Locks, reservoirs, and lakes
• Flumes and weirs
• Holding tanks

Gauge Advantages

Available in aluminum, fiberglass, and stainless steel, Openchannelflow staff gauges last considerably longer than other gauge materials.  They do not rust or corrode in even the harshest of marine or treatment plant environments.  

Maintenance is minimal as any algae, organic growth, or marine organisms that buildup on the gauge can be easily washed off.

Openchannelflow staff gauges are suitable for direct mounting to a wall or pier. They can be mounted to a backing board of redwood, cedar, or composite and then attached or embedded into the wall.   

Unlike porcelain staff gauges, grommets are not needed when installing stainless steel staff gauge and are not usually necessary on fiberglass ones.  Rubber washers are usually sufficient to ensure that the screw head doesn’t spall the fiberglass.

Gauge Readability

Using the same Clearview Highway font used on interstate signs, Openchannelflow freestanding staff gauges are designed to be read easily at a glance and a distance.  

The font is scaled to industry legibility standards to maximize readability and minimize read error.

While Clearview Highway can't be used for metal gauges - it isn't designed for stencil cutting - a similar stencil-friendly font is used.

Gauge Layouts

Openchannelflow offers both standard USGS (A/C/E/I/M) and custom layouts.  Custom layouts can be single or multi-scale as needed. 

Multi-scale gauges can mix any number of different level and flow units.  For Flumes and Weirs, the ability to show both the water level and the flow rate on the same gauge is handy when only manual flow readings are taken.

Custom gauges also allow for the use of multiple colors.  Whether at specific water levels or in zones of level, color can be used to let operators quickly identify the installation's status. 

Gauge Materials

Fiberglass

• In fiberglass, graphics are usually black on high visibility background to maximize readability, although other combinations are available:  
  • Black on high visibility yellow/green (standard)
  • Black on white
  • Black on reflective white
  • White on reflective red
  • White on green
• Major increment markings can also be presented in a mix of colors for easy visual recognition.
• Customization is the greatest in fiberglass. Graphics can be of any style, size, or orientation desired.

Stainless Steel

• Stainless steel staff gauges are stencil cut through the gauge.  The gauges can sandwich a high visibility background between the gauge and a backer plate where more readability is needed. 
• Stainless steel staff gauges use a stencil cut font more suitable to the application - Clearview Highway not lending itself to stencil cutting.  
• Stencil cutting limits the customization that can be done as the cutouts need to be legible at a distance.
• Stainless steel gauges are available in T-304 and T-316 construction.

Aluminum

• As with stainless steel gauges, aluminum staff gauges are stencil cut through the gauge.  Gauge visibility can be improved using a contrasting backer plate or by painting the surface behind the gauge. 
• Both aluminum and stainless steel staff gauges use the same stencil cut font (as Clearview Highway was not designed for this application).  
• Gauge markings for all stencil cut metal gauges are limited by the thickness of the material.  Finer materials can have finer layouts, while thicker gauge requires thicker / larger cutouts to be readable at a distance.

Gauge Mounting

Most gauges are made for mounting to a vertical surface.  However, gauges can be made for mounting to inclined - or even circular - surfaces.

When designed for non-vertical surfaces, the gauge layout is adjusted so that the gauge indicates the corrected reading for vertical head - there is no need to scale or adjust the observed level.  This layout, in turn, reduces the likelihood that an error in reading or recording the water level will be made.

Note that gauges intended to mount to round structures are limited in how tight the diameter can be due to the backing material's flexibility.

Image:  Wikipedia