DIRECT DIGITAL CONTROL OF A WASTEWATER TREATMENT
FACILITY WITH REMOTE OPERATION
Douglas G. Whitaker, Water Resources Administrator
Wesley A. Flower, Waste Treatment Engineer
The Miami Conservancy District
Dayton, Ohio 45402
INTRODUCTION
Waste treatment management can no longer be viewed as a static process which merely
requires the subjective analysis of historical data.   The enactment of the 1972 Water
Quality amendments, under the National Pollutant Discharge Elimination System, has
established quantitative limits for each wastewater treatment facility discharging into the
nation's waterways, which will require the expenditure of many millions of dollars.   It
is therefore logical to provide a waste treatment management system which assures that
treatment plants will be operated optimally through immediate response to process
changes.   Traditionally, operation of wastewater treatment plants has been a heuristic
process involving manual sensing and manual response.   In most municipal and large industrial wastewater treatment systems, manual control of the process cannot consistently
provide effluent quality within the NPDES discharge limitations.   Anticipating this problem as far back as 1969, the Miami Conservancy District initiated efforts to improve the
technical management of wastewater treatment plants which evolved into the development of the Franklin digital control and monitoring system.
The Miami Conservancy District has operated a water quality program in the Great
Miami River basin since 1967.   Organized and financed by local governments and industry,
a continuing regional water quality management program was developed which includes
the operation of six continuous water quality monitors, an extensive stream sampling program, a water quality laboratory and the design, construction and operation of wastewater
treatment plants.
Several significant observations with respect to wastewater treatment operation have
resulted from the District's water quality program:
1. Treatment plants designed to provide high levels of treatment seldom do so consistently, partially due to design considerations and partially due to operation
and management techniques.
2. Waste treatment plants in general do not possess the level of control necessary
to consistently achieve the water quality objectives.
3. There is a shortage of highly trained technical personnel to adequately assure
high levels of quality control of treatment systems, particularly at the small and
medium-sized plants.
These observations had a significant influence on the design and implementation of the
District's Franklin area wastewater treatment plant, and resulted in the decision to install
a digital control and monitoring system.
To overcome the above listed shortcomings of traditional wastewater treatment operations, it was clear that the critical decisions regarding plant operation must be made by
an engineering-level individual who has in-depth knowledge of the process and who has at
his disposal up-to-the-minute information on all process parameters.   Such a system requires on-line instrumentation and the ability to statistically reduce the information, i.e.,
by computer.   Having established the need for the computer in this regard, the next logical step is direct digital control.   Extending this concept further leads to the idea of an
off-site control center where several treatment plants can be monitored and controlled by
only a few highly trained personnel.
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