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 CHAPTER 2
PROBLEM IDENTIFICATION AND ASSESSMENT
INTRODUCTION
Perhaps one of the most important aspect of water quality enhancement is identification of the
water quality problem(s) and a robust analysis of the cause(s). This is the next step after an
understanding of watershed-reservoir processes has been achieved. Problem identification requires
detection of the problem, definition of the problem (e.g., what is the problem as perceived by water
resource users or indicators), and identification of possible causes or sources of the problem. Often, a
specific and detailed assessment of processes in the watershed, reservoir, and tailwater are necessary
to develop the level of understanding in a particular system so that feasibility of enhancement techniques
can be evaluated. This session will provide an overview of problem definition with input from
workshop participants and detailed information for assessing processes in the watershed, reservoir, and
tailwater.
2.1 WATER QUALITY PROBLEM DEFINITION AND DETECTION
What is a water quality problem? This answer to this question is a function of many factors
such as: user needs, user perceptions, regional conditions, and water quality indicators.
A water quality problem is often not considered problematic until a user is no longer able to use the
resource due to water quality. For example, an algal bloom that decreases turbidity (water clarity) at a
swimming beach such that the beach must be closed becomes a water quality problem. This same algal
bloom may or may not impair other uses such as fishing, boating, or water supply. Consequently, the
perception of a problem will be different depending on the user. Furthermore, in an area of the country
with highly productive lakes and reservoirs, algal blooms are more common than in areas of low
productivity and may be more tolerable. The timing and magnitude of the algal bloom may also
determine the extent of the problem. The use of water quality indicators may help in evaluating water
quality problems but are most appropriately applied on a regional basis with consideration for user
needs.
2.1.1 PERCEPTIONS OF WATER QUALITY PROBLEMS
Beauty is in the eye of the beholder and water quality problems are often defined by
perceptions based on user experiences and requirements. A person accustomed to a eutrophic system
with high algal biomass and low water clarity may be satisfied with the local conditions until he or she
travels to an area with considerably better water quality. Upon return to the local spot, it becomes
apparent that water quality is substandard and has been all along. Fishermen have different water
quality perceptions than do recreational boaters suggesting user requirements may influence water
quality perceptions. Just as important, are perceptions of water quality by nonusers. For example, a
2.1-1
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