Flumes - Manholes - Shelters - Buildings - Enclosures - Weirs - Staff Gages measurement, conditioning, control, water, wastewater, irrigation, rights, flume, parshall, palmer, bowlus, hs, h, hl, trapezoidal, montana, rbc, fiberglass, frp, manhole, packaged, metering, pmm, grinder, energy, absorb, storm, screenings, diversion, shelter, building, equipment, single, piece, modular, staff, gauge, enclosure, sampler, custom Openchannelflow manufactures worldclass Flumes, Manholes, Weirs, and Gauges to measure, condition, and control the flow of water, as well as fiberglass Shelters, Buildings, and Enclosures to fill a range of chemcial equipment protection and storage needs.