ASTM D6146-97(2002)
(Guide)Standard Guide for Monitoring Aqueous Nutrients in Watersheds
Standard Guide for Monitoring Aqueous Nutrients in Watersheds
SCOPE
1.1 Purpose—This guide is intended to provide general guidance on a watershed monitoring program directed toward the plant nutrients nitrogen and phosphorus. The guide offers a series of general steps without setting forth a specific course of action. It gives assistance for developing a monitoring program but not a program for implementing measures to improve water quality.
1.2 This guide applies to waters found in streams and rivers; lakes, ponds, and reservoirs; estuaries; wetlands; the atmosphere; and the vadose and subsurface saturated zones (including aquifers). This guide does not apply to nutrients found in soils, plants, or animals.
1.3 Nutrients as used in this guide are intended to include nitrogen and phosphorus in dissolved, gaseous, and particulate forms. Specific species of nitrogen include: nitrate, nitrite, ammonia, organic, total Kjeldahl, and nitrous oxide. The species of phosphorus include total, total dissolved, organic, acid-hydrolyzable, and reactive phosphorus as described in (2)
1.4 Safety—Health and safety practices developed for a project may need to consider the following:
1.4.1 During the construction of sampling stations:
1.4.1.1 Drilling practices during monitoring well installations,
1.4.1.2 Overhead and underground utilities during monitoring well drilling,
1.4.1.3 Traffic patterns/concerns during sampling station installation,
1.4.1.4 Traffic patterns/concerns during surveying sampling station locations and elevations,
1.4.1.5 Drilling through materials highly contaminated with fertilizers, and
1.4.1.6 Installing monitoring equipment below the soil surface.
1.4.2 During the collection of water samples:
1.4.2.1 Using acids for sample preservation,
1.4.2.2 Sampling during flooding events and ice conditions,
1.4.2.3 Traffic on bridges,
1.4.2.4 Condition of sampling stations following flood events,
1.4.2.5 Sampling of water or soils, or both, highly contaminated with fertilizers,
1.4.2.6 Conditions of sampling stations resulting from vandalism,
1.4.2.7 Adverse weather conditions, and
1.4.2.8 Transporting liquid samples.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
General Information
Relations
Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation:D6146–97 (Reapproved 2002)
Standard Guide for
Monitoring Aqueous Nutrients in Watersheds
This standard is issued under the fixed designation D 6146; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
INTRODUCTION
Various forms of nitrogen and phosphorus are plant nutrients, both naturally occurring and
manmade, that can threaten water resources. Nutrients that run off or infiltrate through the soil profile
canresultinunfishableandunswimmablestreams,lakes,andestuaries,andunsafesurfaceandground
water used for drinking. High concentrations of nitrate in drinking water are a threat to young infants,
and surface waters can suffer from algal blooms, fish kills, and unpalatable and unsafe water for
swimming and drinking. Nutrients are also added to watersheds via chemigation.
This guide recommends a process for developing and implementing monitoring projects for
nutrients in a watershed. It follows Guide D 5851 with more specifics applicable to watersheds and
nutrients. These guidelines are presented for use in the nationwide strategy for monitoring developed
by the Intergovernmental Task Force on Monitoring (ITFM). The nationwide monitoring strategy is
an effort to improve the technical aspects of water monitoring to support sound water quality
decision-making. It is needed to integrate monitoring activities more effectively and economically to
achieve a better return of investments in monitoring projects (1).
Guide D 6145 is offered as a guide for monitoring actual and potential nonpoint and point source
pollution within a watershed. The guide is applicable to surface water and ground water resources,
recognizing the need for a comprehensive understanding of naturally occurring and manmade impacts
to the entire watershed hydrologic system.
1. Scope action.Itgivesassistancefordevelopingamonitoringprogram
butnotaprogramforimplementingmeasurestoimprovewater
1.1 Purpose—This guide is intended to provide general
quality.
guidance on a watershed monitoring program directed toward
1.2 Thisguideappliestowatersfoundinstreamsandrivers;
the plant nutrients nitrogen and phosphorus. The guide offers a
lakes, ponds, and reservoirs; estuaries; wetlands; the atmo-
series of general steps without setting forth a specific course of
sphere; and the vadose and subsurface saturated zones (includ-
ing aquifers). This guide does not apply to nutrients found in
soils, plants, or animals.
This guide is under the jurisdiction ofASTM Committee D19 on Water and is
the direct responsibility of Subcommittee D19.02 on General Specifications,
1.3 Nutrients as used in this guide are intended to include
Technical Resources, and Statistical Methods.
nitrogen and phosphorus in dissolved, gaseous, and particulate
Current edition approved June 10, 1997. Published October 1997.
forms. Specific species of nitrogen include: nitrate, nitrite,
The boldface numbers given in parentheses refer to a list of references at the
end of this standard. ammonia, organic, total Kjeldahl, and nitrous oxide. The
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D6146–97 (2002)
species of phosphorus include total, total dissolved, organic, D 4410 Terminology for Fluvial Sediment
acid-hydrolyzable, and reactive phosphorus as described in (2) D 4448 Guide for Sampling Ground Water Monitoring
1.4 Safety—Health and safety practices developed for a Wells
project may need to consider the following: D 4696 Guide for Pore-Liquid Sampling from the Vadose
1.4.1 During the construction of sampling stations: Zone
1.4.1.1 Drilling practices during monitoring well installa- D 4700 Guide for Soil Sampling from the Vadose Zone
tions, D 5092 Practice for Design and Installation of Ground
1.4.1.2 Overhead and underground utilities during monitor- Water Monitoring Wells in Aquifers
ing well drilling, D 6145 Guide for Monitoring Sediment in Watersheds
1.4.1.3 Traffic patterns/concerns during sampling station D 5851 Guide for Planning and Implementing a Water
installation, Monitoring Program
1.4.1.4 Traffic patterns/concerns during surveying sampling
station locations and elevations, 3. Terminology
1.4.1.5 Drilling through materials highly contaminated with
3.1 Definitions:
fertilizers, and
3.1.1 For definitions of terms used in this guide, refer to
1.4.1.6 Installing monitoring equipment below the soil sur-
Terminology D 1129 and Guide D 5851.
face.
3.2 Definitions of Terms Specific to This Standard:
1.4.2 During the collection of water samples:
3.2.1 aquifer—a geologic formation containing water, usu-
1.4.2.1 Using acids for sample preservation,
ally able to yield appreciable water.
1.4.2.2 Sampling during flooding events and ice conditions,
3.2.2 ground water—thatpartofthesubsurfacewaterthatis
1.4.2.3 Traffic on bridges,
the saturated zone. (D 653, D18)
1.4.2.4 Condition of sampling stations following flood
3.2.3 nonpoint pollution—a condition of water within a
events,
water body caused by the presence of undesirable materials
1.4.2.5 Sampling of water or soils, or both, highly contami-
from diffuse locations with no particular point of origin.
nated with fertilizers,
3.2.4 vandose zone—the zone of soil located between the
1.4.2.6 Conditions of sampling stations resulting from van-
surface and the water table that is not saturated.
dalism,
3.2.5 watershed—all lands enclosed by a continuous hydro-
1.4.2.7 Adverse weather conditions, and
logic surface drainage divide and lying upslope from a speci-
1.4.2.8 Transporting liquid samples.
fied point on a stream. (D 4410, D19)
1.5 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
4. Significance and Use
responsibility of the user of this standard to establish appro-
4.1 The user of this guide is not assumed to be a trained
priate safety and health practices and determine the applica-
technical practitioner in the water quality field.The guide is an
bility of regulatory limitations prior to use.
assembly of the components common to all aspect of water-
shed nutrient monitoring and fulfills a need in the development
2. Referenced Documents
of a common framework for a better coordinated and a more
2.1 ASTM Standards:
unified approach to nutrient monitoring in watersheds.
D 515 Test Methods for Phosphorus in Water
4.2 Limitations—This guide does not establish a standard
D 653 Terminology Relating to Soil, Rock, and Contained
procedure to follow in all situations and it does not cover the
Fluids
detail necessary to meet all of the needs of a particular
D 1129 Terminology Relating to Water
monitoring objective. Other standards and guides included in
D 1357 Practice for Planning the Sampling of the Ambient
the references describe the detail of the procedures.
Atmosphere
D 1426 Test Methods for Ammonia Nitrogen in Water
5. Monitoring Components
D 1739 TestMethodforCollectionandAnalysisofDustfall
5.1 A watershed monitoring program of nutrients is com-
(Settleable Particulate Matter)
prised of a series of steps designed to collect nutrient data to
D 3370 PracticesforSamplingWaterfromClosedConduits
achieve a stated objective. The purposes of monitoring may be
D 3590 Test Methods for Total Kjeldahl Nitrogen in Water
several and include: analyzing trends, studying the fate and
D 3856 Guide for Good Laboratory Practices in Laborato-
transport of nutrients, defining critical areas, assessing compli-
ries Engaged in Sampling and Analysis of Water
ance, measuring the effectiveness of management practices,
D 3858 Test Method for Open-Channel Flow Measurement
testing for sufficient levels, making wasteload allocations,
of Water by Velocity-Area Method
testing models, defining a water quality problem, and conduct-
D 3867 Test Methods for Nitrite-Nitrate in Water
ing research (3).
5.1.1 Monitoringtoanalyzetrendsisusedtodeterminehow
water quality is changing over time. In some cases baseline
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
monitoring is included as the early stage of trend monitoring.
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
5.1.2 Fate and transport monitoring is conducted to deter-
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. mine whether pollutants move and where they may go.
D6146–97 (2002)
5.1.3 Water quality monitoring can be used to locate critical directly to the achievement of objective B?” If it does then
areas within watersheds exhibiting greater pollution loading objective A feeds into objective B and a diagram can be built
than other areas. showing all possible objectives and their linkages.
5.1.4 Nutrient monitoring may also be used to assess 5.3.1 To assess whether objectives are being achieved,
compliance with water quality plans or standards.
objective attributes could be determined. Attributes define the
5.1.5 Nutrient monitoring may assess the effectiveness of level of achievement for each objective. They answer the
individual management practices in improving water quality question of how close are we to achieving our goals? For
or, in some cases, may be used to evaluate the effect of an example, are we 50 % of the way to achievement? These
entire nutrient management program in a watershed. attributes for nutrient monitoring objectives are often binary;
that is, either the objective is accomplished or not.
5.1.6 The testing of nutrient levels in water bodies may be
used to see if sufficient amounts are present to support certain 5.4 Step 3: Statistical Design—A statistical experimental
aquatic organisms. design should be stated that is consistent with the objectives of
the monitoring program. Appropriate experimental designs
5.1.7 Monitoring of receiving water bodies may be used to
could include: reconnaissance, plot, single watershed, above-
determine wasteload allocations between point and nonpoint
and-below, two watersheds, paired watershed, multiple water-
sources. Such allocations require a thorough knowledge of the
sheds, and trend stations (3). The design selected will dictate
individual contributions from each source.
most other aspects of the monitoring project including the
5.1.8 Nutrient monitoring may be used to fit, calibrate, or
study scale, the number of sampling locations, the sampling
test a model for local conditions.
frequency, and the station type.
5.1.9 Nutrient monitoring may be used for research ques-
5.4.1 Reconnaissance or synoptic designs may be used as a
tions such as the accuracy of different types of samplers in
preliminary survey where no data exist or to assess the
collecting a representative sample.
magnitude and extent of a problem. This type of sampling
5.1.10 Finally, nutrient monitoring may be used to give
could be used to identify critical areas as well. A critical area
adequate definition to a water quality problem or determine
is one that is contributing a significant amount of nutrients to
whether a problem exists. Guide for Planning D 5851 provides
the water body of interest. Randomization in sampling loca-
overall guidance on water monitoring.
tions may be important for reconnaissance monitoring. Recon-
5.1.11 Thisguidesuggestsanddiscussesthefollowingsteps
naissance monitoring could be used in a “whole aquifer” study
in designing a watershed monitoring program for nutrients.
with well placement located randomly or on a grid basis.
More detail on each step may be found in (3).
5.4.2 Plot designs have been commonly used in agricultural
5.2 Step 1: Water Quality Need—The first step is to define
experiments for 100 years (4). Plots are generally small areas
the need for nutrient monitoring. The need statement should
that can be replicated on the land or waterscape. Plots allow
include several components: the potential or real water quality
replication and control of certain variables, such as soil type.
issue requiring attention (for example, eutrophication), the
Plot designs are analyzed using Analysis of Variance (3).
potential water resource use impairment (for example, recre-
5.4.3 The single watershed before-and-after approach has
ation), the name of the actual water resource (for example,
been sometimes used to compare water quality conditions
Long Lake), the potential threats or causes (for example,
before a watershed treatment to after. Generally, this technique
phosphorus), and the potential sources that may cause a
is not recommended, since the results are confounded with
problem (for example, agriculture) (3). Very often the need is
time and climate variables, and should be avoided. For
toidentifyawaterqualityproblem,butinsomecases,theneed
example, the water quality differences from year-to-year may
may be to assess the existing water quality whether a problem
be caused by climate differences not the watershed activity.
exists or not. An example of a need statement might be: “The
lack of recreation in Long Lake is due to excessive eutrophi- 5.4.4 The above-and-below design is used after a watershed
practice is in place. Sampling is conducted both upstream and
cation caused by excessive phosphorus loading possibly from
agricultural sources.” downstream, or in the case of ground water monitoring,
up-gradient and down-gradient from the activity of interest.
5.3 Step 2: Objectives—The second step in developing a
Although this design is not as susceptible to the effect of
nutrient monitoring program is to define the monitoring objec-
climate as the single watershed design, the differences in water
tives. The objectives of the monitoring study should address
quality between the two stations may be partly due to inherent
the water quality need or problem. An objective statement
watershed differences such as soils or geology. If monitoring is
should include an infinitive verb, an object word or phrase, and
conducted before and after the practice in installed, the design
some limits on the objective such as the surface or ground
would follow the paired watershed approach described below.
water resource or watershed boundaries and variables to
monitor. An example of a monitoring objective might be: “To 5.4.5 Ground water monitoring using this approach is re-
determine the effect of implementing agricultural management ferred to as up-gradient versus down-gradient monitoring.This
practices on phosphorus concentrations in Long Lake.” When is probably the most commonly used strategy in ground water
severalobjectivesareused,ahierarchialapproachma
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.