Maximizing Your Monitoring Power
Online water-quality analyzers offer time-saving solutions for dealing with pending EPA regulations related to nutrients in wastewater and water
- By M. Y. Z. Aboul Eish, Ph.D., Robert H. Clifford, PhD
- Oct 01, 2007
As water and wastewater facilities
prepare for pending U.S. Environmental
Protection Agency (EPA)
criteria on water nutrient levels, online
monitoring systems are proving to be an
effective and efficient means of regulating
Water nutrient guidelines originate
from the Clinton administration’s Clean
Water Action Plan, which led to a
national strategy to develop nutrient criteria
in lakes, streams and rivers. On
June 25, 1998, the notice of the National
Strategy for the Development of
Regional Nutrient Criteria was published
in the Federal Register (Volume 63,
Number 122, pages 34648-34650). In
the plan, the government called on EPA
to accelerate the development of scientific
information concerning the levels of
nutrients that cause water problems.
EPA’s goal is to accelerate the progress of
state adoption of numeric water quality
standards, while building the scientific
and technical infrastructure for developing
new nutrient criteria. Once established,
numeric standards reduce states’
time and effort to establish total maximum
daily loads and permits to control
The Trouble with Nutrients
Overuse of fertilizers, which contain
three basic plant nutrients -- nitrogen,
phosphorus and potassium -- has resulted
in the increasing contamination of
surface water and groundwater.
Although these nutrients are critical to
the development of plant and animal life,
they have the potential to be harmful if
ingested by humans and animals.
Nutrient-rich ponds and streams
undergo eutrophication, water pollution
caused by excessive plant nutrients. This
process depletes oxygen levels in water,
causing an accelerated growth of algae
in the waterways. Algae then can cloud
the water, effectively blocking sunlight
from submerged aquatic vegetation.
Excessive algae also can decrease biological
diversity and populations, resulting
in diminished populations of game and
While the risks of excessive nutrients
are many, too few nutrients may result
in insufficient enrichment of the
aquatic food chain, which would be
detrimental to a healthy aquatic biological
Considering the hazards posed by
undesirable nutrient levels, EPA and state
agencies have begun refining and implementing
adequate water quality standards
to provide goals for industries to
reduce their outflow of nutrients such as
nitrogen and phosphorous into waterways.
Permits are being issued for facilities
that regulate discharge and will soon
be required to meet the set standards.
So Long to Tradition
Water-quality analyzers have been an
integral part of industrial and wastewater
treatment applications for years.
However, the traditional water analyzing
techniques are manual, costly, timeconsuming
and often inaccurate.
In addition, the samples are sent to a
laboratory for nutrient level testing,
which can take several days or even up
to a week for results. This means that if
the sample is contaminated, there is a
delay in treating the water. These delays
make it difficult to effectively optimize
and control treatment processes.
In an effort to reduce the labor and
cost, many facilities have dramatically
cut the number of hours specified for
the monitoring process. Because less
time is being dedicated to the monitoring
process, less information is being
provided about nutrient levels. Therefore,
water has the potential to be
overtreated or even undertreated.
Additionally, a reduction in sampling
hours means that pertinent criteria
regarding nutrient levels may not be
made readily available.
As facilities seek greater analyzing
effectiveness through alternative techniques,
a new breed of sampling and
treatment equipment has entered the
market. Automated online sampling is
rapidly gaining recognition for various
measuring and operational tasks in
both the water and wastewater sectors.
New Technology Yields Better Results
Online monitoring technology enables
real-time monitoring of water and
wastewater for municipal and industrial
applications. Less cumbersome than
conventional methods, online analyzers
are easy to operate and specifically
intended to prepare facilities for the
EPA’s pending nutrient level regulations.
With online technology, a computercontrolled
system automatically pumps
water samples to the analyzer in the
facility lab. The time-saving technology
provides comprehensive water quality
analysis onsite, eliminating the need to
manually collect the samples. In addition,
results from onsite analytical
instrumentation are obtained quickly,
and there is no need for outside laboratory
testing. Because of the minute-tominute
analyzing capabilities of the single-
unit technology, more details are
provided about nutrient levels within
the day. The red circle in the chart indicates
a sudden change in relative total
phosphorous, one that may not have
been detected with manual monitoring
Online analyzers are capable of
simultaneously measuring specific
nutrients such as total nitrogen and
total phosphorous in water. This device
also comes equipped with calculators
that act as an alarm for specific actions
such as error checking. In addition, the
online technology can pretreat, digest,
and analyze samples automatically, and
eliminate errors in sample preparation.
Through an automated monitoring
and analysis process, the analyzers
provide facilities with advanced technology
that helps accelerate the reduction
in pollutants discharged and minimizes
the health risk involved accordingly.
These online sampling devices, which
provide continuous monitoring, also
reduce the energy, resources and materials
used in the sampling process.
An Effective Solution
Removal of nitrogenous compounds
from water and wastewater is critical,
as excessive nitrate levels in discharged
effluent can pose a threat to our environment.
With new requirements to
control nutrient discharge currently
under way, effectively monitoring nutrients
in water and wastewater will
become increasingly important.
Automated continuous sampling
devices are proving to be a reliable and
easy environmental monitoring tool,
providing a good and economical option
to traditional techniques.
This article originally appeared in the 10/01/2007 issue of Environmental Protection.
M. Y. Z. Aboul Eish, Ph.D., formerly worked for Shimadzu Scientific Instruments.
Robert H. Clifford, PhD, has been with Shimadzu Scientific Instruments for 16 years, currently holding the position of TOC Product Manager. Prior to Shimadzu, Clifford worked at the U.S. Food and Drug Administration for four years. He can be reached at 800-477-1227.