Although initially developed to measure runoff from watersheds and experimental plots, the H Flume has proven to be quite flexible in its mounting configurations.

Below Grade 

For below grade applications, HS and H Flumes up to 2-feet in size can be:

• Factory integrated into fiberglass packaged metering manholes
• Field installed in a concrete vaults

 

For shallow below grade (typically only a foot or so below grade), HS and 0.5-Foot H flumes can be factory integrated into fiberglass enclosures. 

Above Grade 

Like shallow below grade application, mounting a HS or 0.5-foot H Flume in a fiberlgass enclsoure works well for above grade applications.  The enclosure keeps the flume secure and and out of sight /  away from prying hands.

All HS Flumes and H Flumes up to 3-feet in size are suitable for unreinforced above grade installations.  Here the flume typically sits on a concrete pad, with threaded rod run through the holes in the standard anchoring clips.

For above grade applications using larger H and HL Flumes, the flume should be embedded in earth or concrete to support the sidewalls under flow conditions.  

Drop Into the Flume

Where the flume is used in a edge-of-field or catchment application, it is not uncommon to recess the flume in the bank of the plot to aid in directing flow into the flume and to minimize upstream ponding.  

A drop into the flume can also take the form of a vertical pipe discharging into the approach section.

The accuracy of the H Flume is impacted by the drop into the flume, but with a sufficiently long approach section (5D) the effect can be minimized.

 

 

Images:  City of Columbia, MO, USDA Agricultural Research Service