Monitoring Program Design
severe streambank and
erosion may have caused a stream bed to be filled
with sand and silt. The biological potential would be limited by habitat impair-
ments that reduce fish reproduction capability. Even with extensive implementa-
and streambanks, the stream may take a long time to
flush excess sediment and achieve an improved habitat condition.
In general, a water resource in a predominantly urban or agricultural watershed has
a lower potential habitat condition than one in a forested watershed. The overall
ecological condition of the resource will be limited by the present and the potential
Problem identification and the careful documentation of the water quality problem
with monitoring are essential for projects interested in improving water quality
through the implementation of
Carefully designing and documenting the water quality problem is one of the most
important steps for NPS pollution control and water quality monitoring. An
effective approach is to implement a problem identification monitoring program
lasting6 to 18 months. Problem identification monitoring uses asite-specific plan
to identify pollution sources and impacts during the seasons of greatest pollutant
Carefully designing and
loading (e.g., spring runoff, snowmelt) and during the season when impairments
are noted (e.g., algal blooms).
documenting the water
quality problem is one of the
Problem Documentation Monitoring Stations
most important steps for
There are three types of problem documentation monitoring stations: a) tributary,
NPS pollution control and
b) main stem stream, and c) wetland or lake. A mixture of station types (depending
upon the situation and cost) may be useful to document the problem.
water quality monitoring.
Tributary stations should be located immediately below suspected pollution
sources. Tributary monitoring helps to identify pollution sources and their
magnitude or to assess habitat limitations. Tributaries may serve as a source of
food for fish or they may provide critical habitat for the managed water resource.
Monitoring the main stem stream (primary drainage channel) alone is inadequate
to identify sources of pollution because the main stem stream dilutes and
assimilates tributary inputs. making identification of pollutant sources areas
Tributary stations are especially useful for identifying pollution sources such as
point sources, animal lots, mobile home parks, quarries, construction sites, and
cropland. Monitoring above and below sources may be needed and is encouraged
if discrete source inputs can be identified and it is necessary to characterize
different sources. Pollutant constituents that match the potential source should be
sampled, along with pollutants that affect the managed resource.
Main stem stream stations serve to show the aggregate of upstream and tributary
effects. Consider chemical, biological, habitat, and streambank analyses that
match the impairment or threat to designated use. Main stem stations should be
located close to suspected sources. Monitoring above and below tributary or point
sources of pollution serves to evaluate their impact. Main stem monitoring shows
the extent that dilution and assimilation affects pollutants and stream quality.
Wetland and lake stations should be selected to match the location of the
impairment or threat to designated use.