Summary #
A well-structured monitoring plan is essential for producing reliable watershed data. This page walks through the key steps: deciding who will monitor, defining the scale, setting goals, choosing indicators and methods, establishing data quality objectives, selecting monitoring sites, determining timing, and documenting everything.
Decide Who Will Monitor #
Once you have decided to monitor a stream, watershed, or other aquatic body, it is important to determine exactly who will be doing the monitoring. Will you hire professionals or ask for volunteers? Volunteer monitoring has many advantages: it is educational, economical, and a valuable source of help. Professional monitoring is often still necessary even if volunteer monitoring is used. However, volunteer monitoring can provide data for remote areas, data more frequently than routine monitoring, an understanding and awareness in watershed residents, and documentation of important plants and animals observed by volunteers.
Define the Scale #
It is very important to define the size of the watershed that you want to monitor. Make sure to choose something large enough to make a difference, but small enough to be manageable. Consider the amount of time and money available to the monitoring project. It will be needed to buy supplies, pay professionals, and manage the monitoring.
Set Goals #
Find out the background on the area you want to monitor. Is there any data already available? Are there water quality standards in place? Are they being met? What are the uses, values, and threats in your watershed? What are your watershed management goals? Are there any questions to answer through monitoring?
Determine the Indicators to Monitor #
Indicators are measurable features that can provide insight into current conditions and trends. The major categories are: Chemical, Physical, and Biological. It is also a good idea to track land use and known pollution sources. Some commonly monitored indicators are pH, dissolved oxygen, temperature, water color, and flow rate.
Determine Data Quality Objectives #
This is very important if many people will be involved in data collection. Be sure to establish data quality objectives (DQOs). This ensures that data will be consistent and useful for end collection and analysis. Important DQO considerations include completeness (how many samples should be taken), representativeness (do your sample results represent the conditions you were monitoring), precision (how close should repeated measurement values be), accuracy (how close should measurements be to the standard), and sensitivity (what is the minimum level of an indicator you must detect).
Decide on Methods #
Once you have established which indicators to monitor and DQOs, you can select the methods for sampling and analyzing the indicators. Physical monitoring can be done through visual surveys or field measurements. Chemical monitoring can use field test kits or laboratory analysis. Biological monitoring is often a combination of field and lab work. When selecting methods, be sure to indicate in your DQOs how many replicates to obtain as well as any special procedures.
Determine Monitoring Sites #
Where monitoring sites are placed is based on the kind of picture you would like to obtain of the watershed. Some suggestions: use your topographical map of the watershed to determine beneficial sites, field-check each site for accessibility and safety, obtain landowner permission for sampling, photograph each site, map each site, and make a list of selected sites including the rationale for choosing them.
Decide When to Monitor #
Determine how frequently monitoring must be conducted. Baseline information is best obtained by sampling regularly, while human impact is often most noticeable before and after storm events. It is best to remain consistent with sampling times during the day as some indicator levels, such as dissolved oxygen, fluctuate through the day. Macroinvertebrates are often most plentiful in the spring and the fall.
Documentation #
Do not forget to document your monitoring plan. Keep clear, concise records detailing the monitoring plan for the watershed, including the indicators, methods, and analysis used. It is also important to have clear records of the monitoring results from data collection. Over time, the data can be compared to the goals originally outlined by the monitoring plan. Clear documentation will allow you to compare the progress of the monitoring plan and revise the goals or methods if needed. Documentation is also a good resource for public outreach, providing solid evidence and support to rehabilitation programs.
For more information on developing and implementing a monitoring plan, obtain Designing Your Monitoring Program: A Technical Handbook for Community-Based Monitoring in Pennsylvania prepared by River Network and PA DEP Bureau of Watershed Management, Citizens’ Volunteer Monitoring Program.
Related Pages #
- Water Quality — What you are measuring
- Establish Sampling Points — Choosing monitoring locations
- Doing It Yourself — Volunteer monitoring approach
- Field Assessment Tools — Equipment for monitoring
- Training the Field Volunteers — Preparing your team
Source and Last Reviewed #
Source: AMR Clearinghouse (amrclearinghouse.org). Migrated to AML-Connect. Last Reviewed: 2026-03-13.
[Admin note: Some external links in this article may be outdated. Verify before relying on them. Flag dead links for removal or replacement.]
Tags: monitoring, assessment, planning, sampling, practitioner
