Total Maximum Daily Load process seeks to improve water quality, inform public

It’s one of those days where you don’t need rain to feel wet all over. The air is as thick as the clouds in the sky. Environmental biologists Katie McKone and Jessica Schuster are knee deep in the Strodes Creek Watershed in Bourbon and Clark Counties to take the same water readings they’ve been taking for the last 18 months. They’re collecting the data necessary to develop a pollutant reduction strategy, known as a Total Maximum Daily Load (TMDL), with the goal of taking the impacted watershed from polluted to meeting water quality standards.   Collecting the necessary data can be difficult, especially when the water is very high or when vegetation surrounding the waterways is more than head high, but it’s an important job because the data gathered here could direct efforts to help make Kentucky’s waterways cleaner and healthier.

Jessica Schuster walks through the Strodes Creek watershed collecting water quality samples

In the lower 48 states, Kentucky ranks in the top 15 for miles of navigable water. But with that water comes the responsibility we all share to keep it clean because, in one form or another, we all live in a watershed. All of Kentucky’s small streams, creeks, rivers and lakes ultimately lead to larger bodies of water like the Ohio River, which eventually leads to the Mississippi River and on to the Gulf of Mexico.

We rely on many of these bodies of water for drinking water supply, swimming, fishing and for other purposes. So the cigarette butt, the oil from your car or the pesticides and fertilizers you spray on your lawn or field, may end up in the water we use for drinking, if not properly managed. Pollution primarily transported by runoff is called non-point source pollution. Point source pollution, on the other hand, is waste released through pipes into waterways from industrial processes and sewage treatment plans, and is regulated by the Kentucky Pollutant Discharge Elimination System (KPDES) permit process.  No matter what pollutants end up in our waterways or their source, they have to be cleaned in water treatment plants before we can drink the water from the taps in our homes.


A TMDL must be written for any waterbody on the 303(d) List of Impaired Waters, according to the Clean Water Act.  A TMDL is kind of like a diet for water ways. If you were trying to lose weight, you might take some time to assess what you’re eating and then change that diet. A TMDL does something similar to improve the water quality of our streams and rivers. It assesses what’s in the stream, and how much of a particular pollutant that stream can assimilate before it has negative effects on water quality and aquatic life. Then, Division of Water scientists give the stream a “diet” of what the stream needs less of in order to meet water quality standards and be healthy once again.

Katie McKone measures flow in the Strodes Creek watershed

A TMDL is made up of a few pieces:  1) a waste load allocation, which is a calculation of the maximum amount of pollutant that can be released from regulated entities (point source pollution), 2) a load allocation, which is a calculation of the maximum amount of pollutant that can be released from runoff pollution (non-point source pollution), and 3) a margin of safety.  To make these calculations, you need a lot of data. That’s why Kentucky Division of Water biologists Jessica Schuster and Katie McKone have been collecting data in the Strodes Creek watershed for almost two years.

Kentucky Division of Water’s biologists Schuster and McKone use instruments to measure flow and depth of streams, collect water chemistry samples, bacteria samples, macroinvertebrate samples and measurements to achieve a big-picture story of the Strodes Creek Watershed.  They work with a team who uses their data to calculate a pollutant reduction strategy, a TMDL.  It’s taken almost two years of getting into the stream, hot, cold or flooded to collect enough data. The data is important because scientists will  be able to determine how much point-source discharges of a parameter must be reduced so water quality standards can be achieved once again. It also gives invaluable information and tools to non-point source contributors, so they can understand the impact they’re having on the waterway. The data will help those contributors on practices they can implement to help the waterway.

In areas where point sources are the predominate source of a pollutant, regulatory programs play a big role in improving and protecting water quality.  For example, a TMDL ensures that the permits written for the regulated community will meet water quality standards.  These facilities are then obligated to meet the standards contained in their permits.

Addressing non-point source pollution can be a greater challenge because there are fewer regulatory programs in place to address runoff.  The agency places an emphasis on educating and partnering with the public and industry to reduce non-point source pollution. Education starts with reaching out to property owners to explain how the waterway is being impacted by activities taking place in the watershed.  The agency also provides landowners with technical assistance and sometimes access to funding to improve the quality of the water running off the property, thereby protecting the environment.

Our charge in the Kentucky Department for Environmental Protection is to protect the environment. By conducting sampling, developing TMDLs, issuing and enforcing permits, and providing education and assistance we are continuing to improve watersheds across the Commonwealth.