Cannery Waste Disposal by Spray
Irrigation—After 10 Years
Helmer Monson, Manager
Civil Engineering
Green Giant Company
LeSueur, Minnesota
Irrigation as a method of cannery-waste disposal has been very successful—as shown by its increase in use from only a few canneries in
1948 to an estimated 250 in 1957. As in the development of most
processes there have been problems. On the other hand, the relief to
streams which this method has afforded is really significant. Although
the water used by canners is not great in comparison to other industries,
its organic content is roughly ten times that of domestic waste. The total
potential biochemical oxygen demand of the waste produced by the
canning industry is estimated to be about 1 per cent of all of industry.
The year 1957 was the 10th that the Green Giant Company used
irrigation as a method for disposal of liquid cannery waste. Actually,
the company's experience with spray irrigation extends back only 8 years
since the first 2 years' effort was based on ridge and furrow application
only.
It was learned early that, except in unusual cases, wastes could not
be applied by the ridge-and-furrow method. Distribution and control of
the waste volumes from a large or even medium-size cannery is very
difficult when applied in this manner. This and other factors including
the maximum infiltration rates of most soils, benefits of a cover crop,
etc., dictated the change to spray application. Although the switch indicated much larger land and equipment requirements the increased costs
were soon accepted and at this time are felt to be reasonable. A compensating factor, farm lands with somewhat steeper slopes, can be utilized.
Application rate, permeability and irrigating frequency are matters
of primary importance. Nevertheless, it is still necessary to use rule-of-
thumb and experience for designing and operating the company's disposal farms. Considerable time and effort have been expended in attempting to tie down these variables but with not too much success. After
spending the summer of 1953 running tests on one farm in Minnesota,
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