Blog

Industries measure their discharges either to meet their NPDES permit or because of municipal / county requirement. For industrial operators charged with monitoring their process discharges, a Packaged Metering Manhole can be a cost effective solution to their flow measurement…

Bubbler style flow meters provide the most accurate measurement of level in open channel applications; more accurate than ultrasonic or even pressure transducer flow meters. Using an internal air compressor to push a measured volume of air through a vinyl or Teflon bubbler line,…

The 36-inch Parshall Flume is equally at home measuring water rights, sanitary flows, and surface waters. The 36-inch Parshall Flume is useful in a number of applications:

Pure and simple, Openchannelflow makes fiberglass Parshall flumes. We aren’t resellers, we aren’t distributors, and we don’t job shop production. What we are is manufacturer of premium quality, dimensionally accurate, and corrosion resistant fiberglass Parshall…

The typical bracket used to mount an ultrasonic sensor over a flume or weir is a contractor fabricated one-off assembly. These assemblies often mount the ultrasonic sensor too high, too close to the flume / weir sidewall, or aren't sufficiently rigid - making accurate flow…

As we have discussed before on this blog, the importance of conditioning and properly transitioning flows into a flume can’t be understated as it can have a dramatic effect on a site’s ability to provide accurate flow data. Openchannelflow offers a number solutions to…

Openchannelflow offers bolt-down covers as an option for flumes and weirs. The covers are suitable whether the flume or weir is above grade, below grade, or installed in a Packaged Metering Manhole.

At flow monitoring stations where a Packaged Metering Manhole is used to measure / sample a flow stream, the flow monitoring and sampling equipment is usually housed either in a dedicated equipment shelter or in a nearby building. There are times, however, when neither option is…

Replacement flume floors (aka "magic bottoms") are designed to correct installation problems associated with setting a flume too low in relation to the channel surrounding channel. They are also useful in correcting installations that have experienced settling.

Nested flumes are traditionally Parshall, Montana, or Cutthroat styles, but Palmer Bowlus flumes can also be successfully nested. The ability to nest flumes inside each other can be use in a variety of applications, including:

Those responsible for collecting and reporting industrial pretreatment discharge information (typically flow, pH, BOD, and temperature) are rarely dedicated professionals. Almost always, environmental discharge monitoring is just one of a laundry list of job duties they have to…

To help the growing list of operators of our fiberglass Packaged Metering Manholes maintain their investments, Openchannelflow has put together an inspection form to standardize the collection and reporting of data useful in establishing maintenance cycles for Packaged Metering…

Packaged Metering Manholes factory integrate a flow measurement flume / weir into a fiberglass manhole to provide a complete, turn-key solution to monitor industrial and municipal flows. Openchannelflow Packaged Metering Manholes come complete and ready for immediate…

Traditionally flumes are used to measure at or below grade flows. These flow are commonly natural channels (gullies, swales, creeks, streams, and rivers) or manmade channels (treatment plants or storm drains) / piping. For these applications the flume can either be cast in place…

The Iowa Institute of Hydraulic Research has posted an excerpt of one of their older videos, Fluid Motion in a Gravitation Field: Flow Over Weirs. The video, developed with the support of the National Science Foundation, covers, among other things, the need for aeration of a weir…

In developing our line of Fiberglass Equipment Shelters, we took a lot of time to look at the most commonly used, but frequently overlooked part: the door.

The Department of Civil Engineering and Geomatics' Hydraulics Laboratory at Universidad Nacional Autónoma de México has an interesting video posted showing the hydraulic profile of a Parshall flume under both free and submerged flow conditions.

Packaged Metering Manholes from Openchannelflow are available with a wide range of options to help customize them to your particular application needs. A key element of this customization is the variety of top styles available, with each top specially engineer for a site’s…

More common on Parshall flumes, end adapters are also available on Cutthroat flumes from Openchannelflow.

Flow Sampling Manholes are specialized manholes designed for: