A Versatile Outdoor Channel for Water
Pollution Investigations
JOHN J. GANNON, Professor
HENRY A. DIRASIAN, Research Associate
JOHN D. PHAUP, Instructor
Department of Environmental Health
School of Public Health
The University of Michigan
Ann Arbor, Michigan
INTRODUCTION
An outdoor experimental channel for water pollution studies has been assembled and operated on the grounds of the Ann Arbor Michigan waste water treatment plant during the summers of 1964 and 1965. The primary focus of investigation during this time has been on the phenomena of biological extraction and
accumulation in terms of its influence on river self-purification, particularly as it
relates to oxygen balance. However, it is expected that in future years studies
will extend into other areas of stream self-purification where the use of the channel
will allow greater experimental control than is possible in natural streams.
To be considered herein will be the channel design, assembly, operation and
hydraulic characteristics, together with some preliminary water quality measurements. These include limited reaeration studies, continuous monitoring of channel water quality, slime growth quantification, dissolved oxygen and BOD relationships under different levels of slime growth, and specialized biological evaluations.
Over the years several investigators have reported on experimental channels
developed for water pollution studies including Streeter (1) describing the Cincinnati channels, McKeown (2) describing the Altamaha River barge channels, Wuhr-
mann(3) describing the Zurich, Switzerland, channels, Zimmerman (4) describing
different channels at this same location, and Ogden, Gibbs and Gameson (5) describing the British channels.
CHANNEL DESIGN
A number of specific design criteria were formulated, including the following: 1) Lightweight material for construction so the channel could be moved from
one location to another; 2) Ability of the channel to withstand the natural elements; 3) Structural rigidity; 4) Ease of assembly; 5) Ability to vary the cross
section as easily and as quickly as possible; 6) Ability to adjust the slope of the
channel as easily as possible, and 7) Provision of suitable supporting equipment.
Review of several possible construction materials indicated that aluminum had
many of these desirable characteristics, and as a result, the decision was made to
use aluminum wherever possible.
To provide as much flexibility as feasible in the design, it was decided to use
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