Water Quality Monitoring
Each year Ohio EPA collects data from streams and rivers in five to seven different areas of the state. See our Long-Term Monitoring Schedule [PDF 1,462K]. A total of 300 to 400 sampling sites are examined, and each site is visited more than once. During these studies, Ohio EPA scientists collect chemical samples, examine and count fish and aquatic insects, and take measurements of the stream. There are three major objectives for the studies:
- To determine how the stream is doing compared to goals assigned in the Ohio Water Quality Standards (WQS);
- To determine if the goals assigned to the river or stream are appropriate and attainable; and
- To determine if the stream’s condition has changed since the last time the stream was studied.
On this page:
General Monitoring Information
What does Ohio EPA do with the data?
Ohio EPA analyzes the data to determine how healthy the stream is and whether the water quality goals established for the stream are appropriate. If the stream is not meeting water quality goals, it is said to be “impaired.” The state is required to prepare a cleanup plan for waters that are impaired; this restoration plan is called a Total Maximum Daily Load. If the goals for the stream are not appropriate, Ohio EPA may change the goals through an administrative rule-making [PDF 90K].
The findings and conclusions of the study are typically documented in a biological and water quality report (see past reports here).
The findings of each biological and water quality study may be used in regulatory actions taken by Ohio EPA. The results are incorporated into Water Quality Permit Support Documents, State Water Quality Management Plans, and the Ohio Nonpoint Source Assessment. This information also provides the basis for the Integrated Water Quality Monitoring and Assessment Report - a biennial statewide report on the condition of Ohio’s waters and the list of impaired and threatened waters required by Sections 303(d) and 305(b) of the Clean Water Act.
How long does the sampling take?
Most of the sampling will be completed by October 31 of this year. Chemical samples for a few sites in your watershed may be collected through next year. If we find that the stream is not meeting water quality goals, then additional measurements may also be made next summer.
Who analyzes the samples?
Most fish sampling occurs in the field and the fish are returned to the stream alive. The macroinvertebrate (aquatic insect) samples are returned to Ohio EPA for processing over the next year. Most of the chemical samples are analyzed at Ohio EPA’s laboratory in Columbus, although local laboratories may be used for some analyses.
If I encounter Ohio EPA staff, is it OK to talk with them?
Please do. Most of the time, the Ohio EPA staff will be happy to answer your questions and talk about what they are doing. In some instances, however, they may not have a lot of time because they need to deliver samples to a laboratory at a specific time.
How can I find out the results of the study?
Over the next several months, the data will be processed, evaluated, and synthesized into tables and written summaries. Frequently, a public meeting about the findings of the study is held in the local area, probably late next year. Typically, a biological and water quality report is written about the survey’s findings (see past reports here).
Announcements about the study and its findings are usually sent to local newspapers. If you want to make sure you know about public meetings and generally stay informed as the process continues, please send your contact information to DSW_TMDL@epa.state.oh.us. In the subject line of your e-mail, please identify your watershed of interest.
What if the streams are meeting water quality goals?
Congratulations. You and your neighbors appear to be doing a good job of taking care of your streams. Since the TMDL addresses only impaired waters, no TMDL is needed if waters are not impaired.
Even though the stream doesn’t need to be restored, it should be protected to maintain its good quality.
2011 Monitoring
What areas are being studied in 2011?
Ohio EPA plans to study the following areas during 2011:
This is less work than originally scheduled in the 2010 Integrated Report because of fewer resources being available. Work in Beaver Creek (Frontal Lake Erie) is postponed to 2012; work in the Little Auglaize River watershed is postponed to 2014; and the work in the Tiffin River watershed is postponed indefinitely. Work in Tenmile Creek was originally scheduled for 2014 but is being done sooner to answer questions in the Maumee River Area of Concern.
2010 Monitoring
The following areas were studied during 2010. Ohio EPA staff may return to these areas to collect additional information during 2011:
2009 Monitoring
The following areas were studied during 2009.
2008 Monitoring
The following areas were studied during 2008.
2007 Monitoring
The following areas were studied during 2007.
2006 Monitoring
The following areas were studied during 2006.
Future Monitoring
Where does Ohio EPA expect to be monitoring next year?
According to our projected schedule (see dark green areas on our Long-Term Monitoring Schedule [PDF 1,171K]), we plan to monitor in the following watersheds in 2012:
- St. Joseph River
- Beaver Creek (Frontal Lake Erie)
- Conotton Creek
- Stillwater Creek
- East Fork Little Miami River
- Mill Creek
- Bokes Creek
However, schedules do change. In 2006, we were able to add monitoring (the Muskingum monitoring was not on the original schedule), but in several years we have had to do less monitoring than planned.
What about monitoring in future years?
Ohio EPA has included the projected long-term monitoring schedule in the Integrated Reports since 2002. The 2010 Integrated Report contains the most recent monitoring schedule.
A number of factors are considered in setting up the long-term monitoring schedule and in deciding where we will monitor in any given year.
- The monitoring schedule is projected based on resources available in 2010. The schedule can change for any number of reasons; projections for 2011-2014 are more certain than for later years.
- The schedule depicts intense full-watershed monitoring as part of the TMDL process. As there are indications of improvements, we will revisit TMDL areas to measure water quality conditions. Such monitoring will be arranged to answer the question being posed and may not include the basin-wide structure typically used to create TMDL plans. As more "revisit" work is needed, future schedules may reflect the impact of resources redirected to this purpose.
- Ohio EPA makes every effort to stretch monitoring and TMDL resources by taking advantage of opportunities to work with others. When suitable opportunities arise, we adjust the monitoring schedule to participate.
- The "Five-Year Monitoring Plan" provided a framework for the schedule. Generally, the 5 color groupings on the map depict the 5 watershed groupings of the monitoring plan, with the color intensity indicating when during the next three cycles the watershed is likely to be monitored.
- Among watersheds not already being addressed by recent monitoring and TMDLs, several factors were examined to produce this schedule, including:
- amount of impervious surface;
- presence of high-value attributes;
- presence of public drinking water supply intakes;
- degree of impairment (impairment rank);
- likelihood of change (population growth);
- presence of major basin initiatives led by others;
- proximity to other selected assessment units; and
- workload capacity of Ohio EPA staff.
Monitoring and TMDLs
What is a TMDL?
A TMDL is a cleanup plan to restore a watershed so it meets water quality goals. A TMDL quantifies water quality problems and their sources, specifies what amount of pollutants must be reduced to meet water quality goals, and provides a basis for taking actions to restore the watershed.
TMDLs are part of the federal Clean Water Act. U.S. EPA must review and approve each TMDL.
Where can I learn more about TMDLs?
A lot has been written about TMDLs in recent years, and several examples of Ohio TMDLs are available. See:
For more information, contact:
Trinka Mount
TMDL Coordinator
Ohio EPA, Division of Surface Water
trinka.mount@epa.state.oh.us
(614) 644-2146