By:  Bill Butler, Lake Watch President
 Appeared in Lake Magazine, October 2025 Edition

It’s that time of year again. Summer has blown by, and now you’re facing all the chores you’ve postponed, as well as new ones, such as what to do with all the leaves lying around your yard.

There are lots of options, but one thing you shouldn’t do is blow them (or your grass clippings) into the lake. I know in the fall there is all that inviting bare space where the lake used to be, but using the lake as a disposal mechanism for your leaves and clippings is harmful to our water quality. Sure, leaves fall naturally into the lake every day, but we don’t need to artificially increase the load put on it.

Water pollution comes in many forms, including nutrient and organic matter pollution. Some nutrients in a lake are good. A lake with no nutrients may be perfectly clear, but it is also nearly sterile. Fish and the other organisms that support them struggle to survive. But a lake that has gone too far the other way is undesirable for fish or humans. Think of the murky farm ponds you have seen that you would not dream of swimming in. A lunker bass can sometimes live in these ponds, but at some point aquatic plants and algae can take over and their decomposition can deplete the oxygen in the water to the point that a fish kill occurs.

Leaves and grass clippings increase the amount of nutrients and organic matter in the lake. Nutrients encourage the growth of algae, which leads to a cloudy, undesirable lake. Any organic matter put in the lake uses up oxygen when it decomposes.

Oxygen in the water is measured as dissolved oxygen, and this is one of the tests Lake Watch volunteers perform as part of their regular monitoring program. A DO level of 6.5 to 8 parts per million is considered ideal. Fish and other aquatic organisms become stressed at levels lower than 5 ppm. My monitoring in open water on the lake typically shows a range between 6 and 8 ppm.

Scientists measure the amount of nutrient pollution in bodies of water by use of a scale called a trophic state index, which ranges from 0 to 100. This subject is addressed in greater detail in the publication jointly produced by Alabama Water Watch and Lake Watch of Lake Martin entitled “Citizen Volunteer Watershed Stewardship of Alabama’s Reservoirs – Lake Martin Watershed” and found on our website at lakewatch.org/info-&-resources.

This document explains, “At the low end of the scale, zero to 39, a lake is clean and clear with a very low concentration of nutrients, pollutants and algae, also called an oligotrophic lake. At the high end of the scale, 50 to 100, a lake is cloudy and green with a high concentration of nutrient pollutants and a dense algae concentration, called a eutrophic lake. Middle-of-the-road lakes with TSI values from 40 to 49 are in between the two extremes in water clarity, nutrients, pollutants and algae concentrations, and are known as mesotrophic lakes.”

Auburn University and the Alabama Department of Environmental Management have been measuring the TSI level in Lake Martin for many years. TSI is determined by measuring the amount of algae suspended in the water, but TSI is complex, with many factors such as the time of year, location, water temperature and amount of flow affecting the findings. Speaking generally, through the years since the late 1980s, the lower part of Lake Martin near the dam has tended to be in the oligotrophic to mid-mesotrophic range, while the upper part near the state Route 280 bridge has tended to be in the upper-mesotrophic to lower-eutrophic range.

However, the last two measurements of TSI in the lower lake, in 2020 and 2023, were the highest and second-highest levels recorded, bordering on eutrophic. The lower lake has been, until recently, the cleanest part of the lake. We are unsure why this trend of increasing nutrient enrichment is occurring, but it needs to be watched.

But back to the fallen leaves. Blowing them into the lake should not be a choice – there are many other options. (Burning is not a good option either, but I’ll let the air pollution folks handle that.) Probably the easiest option is mowing over the leaves with a mulching mower and leaving the clippings in place. They will gradually decompose and provide free fertilizer and organic material to your lawn.

My favorite method is composting them. There are lots of online guides for composting, but it is as simple as containing the leaves in a pile, adding green matter such as grass clippings and kitchen vegetable scraps when you can, keeping the pile moist, stirring it up once in a while and letting it decompose. You will get better and quicker results if you chop the leaves up first. You will eventually have compost that is better and much cheaper than what you would buy at the garden center, which certainly appeals to my thrifty nature.

Visit LakeWatch.org or aces.edu for lots of good information on composting and other yard topics.

Another idea: Treeless neighbors and friends might be glad to take the leaves off your hands. My mother used to patrol our neighborhood, looking for bags of oak leaves other people were throwing away. She had beautiful flower beds.

Of course, if you use a lawn service you can just have it haul the leaves away or bag them and put them in your garbage can. Neither of these options are great, but they beat putting them on the lake bed.

One added benefit is the lake will be a lot quieter without all the blowers. Which brings us to noise pollution, but maybe that’s an article for another time.

With the time you will save not blowing leaves, please consider joining us in Lake Watch. 

Bill Butler is a retired attorney, long-time resident of Lake Martin and president of Lake Watch of Lake Martin after drawing the short straw